ML20353A369

Enclosure 11 - 10-Q Filed Period 09/30/2020

ML20353A369
Person / Time
Site:	Callaway
Issue date:	09/30/2020
From:	Ameren Missouri
To:	Office of Nuclear Security and Incident Response
Shared Package
ML20353A355	List: ML20353A356 ML20353A359 ML20353A360 ML20353A361 ML20353A362 ML20353A363 ML20353A367 ML20353A368 ML20353A369 ML20353A372 ML20353A373 ML20353A374 ML20353A375 ULNRC-06624, Enclosure 8 - 10-K Filed 02/28/2020
References
ULNRC-06624
Download: ML20353A369 (90)

Text

Enclosure 1 1 to ULNRC-06624 1 O-Q FILED PERIOD 09/30/2020

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q Quarterly report pursuantto Section 13 or 15(d) ofthe Securities Exchange Act of 1934 for the Quarterly Period Ended September 30, 2020 OR D

Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to

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Im8rofl Exact name of registrant as specified in its charter; Commission State of Incorporation; IRS Employer File Number Address and Telephone Number Identification No.

1-14756 Ameren Corporation 43-1723446 (Missouri Corporation) 1901 Chouteau Avenue St. Louis, Missouri 63103 (314) 621-3222 1-2967 Union Electric Company 43-0559760 (Missouri Corporation) 1901 Chouteau Avenue St. Louis, Missouri 63103 (314) 621-3222 1-3672 Ameren Illinois Company 37-0211380 (Illinois Corporation)

I 0 Executive Drive Collinsville, Illinois 62234 (618) 343-8150 Securities Registered Pursuant to Section 12(b) of the Act:

Title of each class Trading Symbol(s)

Name of each exchange on which registered Common Stock, $0.01 par value per share AEE New York Stock Exchange

Accelerated filer Smaller reporting company Accelerated filer Smaller reporting company D

Accelerated filer Smaller reporting company Non-accelerated filer El Emerging growth company Non-accelerated filer D

Emerging growth company Non-accelerated filer D

Emerging growth company Ameren Corporation Union Electric Company Ameren Illinois Company Ameren Corporation Union Electric Company Ameren Illinois Company Registrant Ameren Corporation Union Electric Company Ameren Illinois Company Title of each class of common stock Common stock, $0.01 par value per share Common stock, $5 par value per share, held by Ameren Corporation Common stock, no par value, held by Ameren Corporation Shares outstanding 247,206,978 I 02,123,834 25,452,373 This combined Form 10-Q is separately filed by Ameren Corporation, Union Electric Company, and Ameren Illinois Company. Each registrant hereto is filing on its own behalf all of the information contained in this quarterly report that relates to such registrant. Each registrant hereto is not filing any information that does not relate to such registrant, and therefore makes no representation as to any such information.

Indicate by check mark whether the registrants: (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1 934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) have been subject to such filing requirements for the past 90 days.

Ameren Corporation Yes No LI Union Electric Company Yes No Ameren Illinois Company Yes No Indicate by check mark whether each registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T ( 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).

Ameren Corporation Yes No Union Electric Company Yes No Ameren Illinois Company Yes No LI Indicate by check mark whether each registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See definitions of large accelerated filer, accelerated filer, smaller reporting company, and emerging growth company in Rule 12b-2 ofthe Exchange Act.

Ameren Corporation Union Electric Company Ameren Illinois Company Large accelerated filer Large accelerated filer Large accelerated filer If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 1 3(a) of the Exchange Act.

LI LI LI LI Indicate by check mark whether each registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

Yes Yes Yes The number of shares outstanding of each registrants classes of common stock as of October 30, 2020, was as follows:

No No No

TABLE OF CONTENTS Page Glossary of Terms and Abbreviations I

Forward-looking Statements PART L Financial Information Item 1.

Financial Statements (Unaudited) 4 Ameren Corporation 4

Consolidated Statement of Income and Comprehensive Income 4

Consolidated Balance Sheet 5

Consolidated Statement of Cash Flows Consolidated Statement of Shareholders Equity Union Electric Company (dlbla Ameren Missouri) 8 Statement of Income 8

Balance Sheet Statement of Cash Flows 10 Statement of Shareholders Equity fl Ameren Illinois Company (dlbla Ameren Illinois) 12 Statement of Income 12 BalanceSheet Statement of Cash Flows 14 Statement of Shareholders Equity Note 1

. Summary of Significant Accounting Policies Note 2. Rate and Regulatory Matters Note 3. Short-term Debt and Liquidity Note 4. Long-term Debt and Equity Financings Note 5. Other Income, Net 23 Note 6. Derivative Financial Instruments 24 Note 7. Fair Value Measurements 25 Note 8. Related-party Transactions Note 9. Commitments and Contingencies Note 10. Callaway Energy Center 33 Note I I

. Retirement Benefits 34 Note 12. Income Taxes 34 Note 13. Supplemental Information 35 Note 14. Segment Information Item 2.

Managements Discussion and Analysis of Financial Condition and Results of Operations Item 3.

Quantitative and Qualitative Disclosures About Market Risk 73 Item 4.

Controls and Procedures PART II. Other Information Item 1.

Legal Proceedings 73 Item IA.

Risk Factors 73 Item 2.

Unregistered Sales of Equity Securities and Use of Proceeds Item 6.

Exhibits 76 77 Signatures

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the availability of federal production and investment tax credits related to renewable energy and Ameren Missouris ability to use such credits; the cost of wind, solar, and other renewable generation and storage technologies; and our ability to obtain timely interconnection agreements with the MISC or other RIOs at an acceptable cost for each facility; advancements in carbon-free generation and storage technologies, and constructive federal and state energy and economic policies with respect to those technologies; labor disputes, work force reductions, changes in future wage and employee benefits costs, including those resulting from changes in discount rates, mortality tables, returns on benefit plan assets, and other assumptions; the impact of negative opinions of us or our utility services that our customers, investors, legislators, or regulators may have or develop, which could result from a variety of factors, including failures in system reliability, failure to implement our investment plans or to protect sensitive customer information, increases in rates, negative media coverage, or concerns about environmental, social, and/or governance practices; the impact of adopting new accounting guidance; the effects of strategic initiatives, including mergers, acquisitions, and divestitures; legal and administrative proceedings; and acts of sabotage, war, terrorism, or other intentionally disruptive acts.

New factors emerge from time to time, and it is not possible for management to predict all of such factors, nor can it assess the impact of each such factor on the business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained or implied in any forward-looking statement. Given these uncertainties, undue reliance should not be placed on these forward-looking statements. Except to the extent required by the federal securities laws, we undertake no obligation to update or revise publicly any forward-looking statements to reflect new information or future events.

3

PART I. FINANCIAL INFORMATION ITEM 1. FINANCIAL STATEMENTS.

AMEREN CORPORATION CONSOLIDATED STATEMENT OF INCOME AND COMPREHENSIVE INCOME (Unaudited) (In millions, except per share amounts)

Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Operating Revenues:

Electric 1,489 1,528 3,846 3928 Naturalgas 139 131 620 666 Total operating revenues I,628 1 659 4,466 4,594 Operating Expenses:

Fuel 141 147 400 409 Purchased power 140 148 383 440 Naturalgaspurchasedforresale 34 31 183 236 Otheroperationsandmaintenance 418 434 1,240 1,301 Depreciation and amortization 273 248 799 745 Taxes other than income taxes 128 131 372 375 Total operating expenses 1,134 1,139 3,377 3,506 Operating Income 494 520 1,089 1,088 Other Income, Net 48 34 117 99 InterestCharges 110 96 311 290 Income Before Income Taxes 432 458 895 897 IncomeTaxes 63 92 134 158 Netlncome 369 366 761 739 Less: Net Income Attributable to Noncontrolling Interests 2

2 5

5 Net Income Attributable to Ameren Common Shareholders 367 364 756 734 Net Income 369 366 761 739 Other Comprehensive Income, Net of Taxes Pension and other postretirement benefit plan activity, net of income taxes of

$, $, $, and $, respectively I

2 1

Comprehensive Income 370 366 763 740 Less: Comprehensive Income Attributable to Noncontrolling Interests 2

2 5

5 Comprehensive Income Attributable to Ameren Common Shareholders 368 364 758 735 Earnings per Common Share Basic I.48 I.48 3.06 2.99 Earnings per Common Share Diluted I.47 1.47 3.04 2.97 Weighted-average Common Shares Outstanding Basic 247.1 245.9 246.8 245.5 Weighted-average Common Shares Outstanding Diluted 249.2 247.5 248.4 247.0 The accompanying notes are an integral part of these consolidated financial statements.

4

September 30, December 31, 2020 2019 6

16 525 393 221 278 71 63 557 494 210 187 1,590 1,431 25,541 24,376 904 847 411 411 1,078 992 993 876 3,386 3,126 30,517 28,933 199 37 109 111 96 164 432 437 2,105 2,505 10,172 8,915 AMEREN CORPORATION CONSOLIDATED BALANCE SHEET (Unaudited) (In millions, except per share amounts)

ASSETS Current Assets:

Cash and cash equivalents Accounts receivable trade (less allowance for doubtful accounts of $44 and $1 7, respectively)

Unbilled revenue Miscellaneous accounts receivable Inventories Other current assets Total current assets Property, Plant, and Equipment, Net Investments and Other Assets:

Nuclear decommissioning trust fund Goodwill Regulatory assets Other assets Total investments and other assets TOTAL ASSETS LIABILITIES AND EQUITY Current Liabilities:

Current maturities of long-term debt Short-term debt Accounts and wages payable Taxes accrued Customer deposits Current regulatory liabilities Other current liabilities Total current liabilities Long-term Debt, Net Deferred Credits and Other Liabilities:

Accumulated deferred income taxes and investment tax credits, net 3,151 2,919 Regulatory liabilities 4,972 4,887 Asset retirement obligations 675 638 Pension and other postretirement benefits 373 401 Other deferred credits and liabilities 438 467 Total deferred credits and other liabilities 9,609 9,312 Commitments and Contingencies (Notes 2, 9, and 10)

Ameren Corporation Shareholders Equity:

Common stock, $01 par value, 400.0 shares authorized shares outstanding of 247.2 and 246.2, respectively 2

2 Other paid-in capital, principally premium on common stock 5,733 5,694 Retained earnings 2,769 2,380 Accumulated other comprehensive loss (15)

(17)

Total Ameren Corporation shareholders equity 8,489 8,059 Noncontrolling Interests 142 142 Totalequity 8,631 8,201 TOTAL LIABILITIES AND EQUITY 30,517 28,933 The accompanying notes are an integral part of these consolidated financial statements.

357 272 640 442 440 874 5

AMEREN CORPORATION CONSOLIDATED STATEMENT OF CASH FLOWS (Unaudited) (In millions)

Cash Flows From Operating Activities:

Net income Adjustments to reconcile net income to net cash provided by operating activities:

Depreciation and amortization Amortization of nuclear fuel Amortization of debt issuance costs and premium/discounts Deferred income taxes and investment tax credits, net Allowance for equity funds used during construction Stock-based compensation costs Other Changes in assets and liabilities:

Receivables Inventories Accounts and wages payable Taxes accrued Regulatory assets and liabilities Assets, other Liabilities, other Pension and other postretirement benefits Net cash provided by operating activities Cash Flows From Investing Activities:

Capital expenditures Nuclear fuel expenditures Purchases of securities nuclear decommissioning trust fund Sales and maturities of securities nuclear decommissioning trust fund Purchase of bonds Proceeds from sale of remarketed bonds Other Net cash used in investing activities Cash Flows From Financing Activities:

Dividends on common stock Dividends paid to noncontrolling interest holders Short-term debt, net Maturities of long-term debt Issuances of long-term debt lssuances of common stock Employee payroll taxes related to stock-based compensation Debt issuance costs Net cash provided by financing activities Net change in cash, cash equivalents, and restricted cash Cash, cash equivalents, and restricted cash at beginning of year Cash, cash equivalents, and restricted cash at end of period Nine Months Ended September 30, 2020 2019 761 802 68 16 I 25 (25) 16 14 (113)

(61)

(190) 154 (55)

(66)

(76) 739 745 56 14 144 (20) 15 (1 1) 10 (4)

(205) 118 147 (56) 11 (41)

(35) 1,329 1,668 (1,884)

(61)

(169)

I 35 (1 761)

(26)

(192) 184 (207) 207 (2)

(3)

(1,981)

(1,798)

(367)

(5)

(168)

(85) 1,263 37 (350)

(5)

(53)

(329) 900 54 The accompanying notes are an integral part of these consolidated financial statements.

(20)

(29)

(11)

(10) 644 178 (8) 48 176 107 168 155 6

AMEREN CORPORATION CONSOLIDATED STATEMENT OF SHAREHOLDERS EQUITY (Unaudited) (In millions, except per share amounts)

Common Stock Three Months Ended September 30, 2020 2019 2$

2 Nine Months Ended September 30, 2020 2019 2$

2 Other Paid-in Capital:

Beginning of period Shares issued under the DRPIus and 401 (k) plan Stock-based compensation activity Other paid-in capital, end of period Retained Earnings:

Beginning of period Net income attributable to Ameren common shareholders Dividends on common stock Retained earnings, end of period Accumulated Other Comprehensive Income (Loss):

Deferred retirement benefit costs, beginning of period Change in deferred retirement benefit costs Deferred retirement benefit costs, end of period Total accumulated other comprehensive loss, end of period Total Ameren Corporation Shareholders Equity 2,161 2,380 2,024 364 756 734 (117)

(367)

(350) 2,408 2,769 2,408 (21)

(17)

2 (21)

(15)

(21)

(15) 8,062 8,489 247.1 245.8 0.1 0.2 247.2 246.0 246.2 0.5 0.5 247.2 244.5 0.7 0.8 246.0 Dividends per common share 0.4950 0.4750 1.4850 1.4250 The accompanying notes are an integral part of these consolidated financial statements.

5,649 5,694 17 37 7

2 5,673 5,733 5,627 54 (8) 5,673 5,716 10 7

5,733 2,525 367 (123) 2,769 (16)

(15)

(15) 8,489 142 2

(2) 142 8,631 Noncontrolling Interests:

Beginning of period Net income attributable to noncontrolling interest holders Dividends paid to noncontrolling interest holders Noncontrolling interests, end of period Total Equity (22)

(21)

(21) 8,062 I 42 5

(5)

I 42 8,204 Common stock shares outstanding at beginning of period Shares issued under the DRPIus and 401(k) plan Shares issued for stock-based compensation Common stock shares outstanding at end of period 142 2

(2)

I 42 8,204 142 5

(5) 142 8,631 7

UNION ELECTRIC COMPANY (dibla AMEREN MISSOURI)

STATEMENT OF INCOME (Unaudited) (In millions)

Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Operating Revenues:

Electric 984 1040 2,386 2517 Naturalgas 17 19 87 98 Total operating revenues 1,001 1,059 2,473 2615 Operating Expenses:

Fuel 141 147 400 409 Purchased power 48 49 124 160 Naturalgaspurchasedforresale 5

6 29 41 Other operations and maintenance 221 242 662 720 Depreciation and amortization 154 138 448 417 Taxes other than income taxes 92 96 254 256 Total operating expenses 661 678 1,917 2003 Operating Income 340 381 556 612 Otherlncome,Net 26 15 55 43 lnterestCharges 50 44 140 136 IncomeBeforelncomeTaxes 316 352 471 519 IncomeTaxes 18 51 29 70 Netincome 298 301 442 449 Preferred Stock Dividends I

I 3

3 Net Income Available to Common Shareholder 297 300 439 446 The accompanying notes as they relate to Ameren Missouri are an integral part of these financial statements.

8

September 30, December 31, 2020 2019 5

263 164 12 30 117 139 44 33 408 373 119 66 968 814 12,991 12,635 904 847 310 285 350 356 1,564 1,488 15,523 14,937 UNION ELECTRIC COMPANY (dibla AMEREN MISSOURI)

BALANCE SHEET (Unaudited) (In millions, except per share amounts)

ASSETS Current Assets:

Cash and cash equivalents Advances to money pool Accounts receivable trade (less allowance for doubiful accounts of $14 and $7, respectively)

Accounts receivable affiliates Unbilled revenue Miscellaneous accounts receivable Inventories Other current assets Total current assets Property, Plant, and Equipment, Net Investments and Other Assets:

Nuclear decommissioning trust fund Regulatory assets Other assets Total investments and other assets TOTAL ASSETS LIABILITIES AND SHAREHOLDERS EQUITY 9

Current Liabilities:

Current maturities of long-term debt 7

92 Short-term debt 234 Accounts and wages payable 256 465 Accounts payable affiliates 70 52 Taxes accrued I 64 24 Interest accrued 59 48 Current asset retirement obligations 53 53 Current regulatory liabilities 40 62 Other current liabilities 102 96 Total current liabilities 751 1,126 Long-term Debt, Net 4,561 4,098 Deferred Credits and Other Liabilities:

Accumulated deferred income taxes and investment tax credits, net 1,689 1,612 Regulatory liabilities 2,898 2,937 Asset retirement obligations 670 634 Pension and other postretirement benefits 129 141 Other deferred credits and liabilities 37 40 Total deferred credits and other liabilities 5,423 5,364 Commitments and Contingencies (Notes 2, 8, 9, and 10)

Shareholders Equity:

Common stock, $5 par value, 150.0 shares authorized 102.1 shares outstanding 511 511 Other paid-in capital, principally premium on common stock 2,027 2,027 Preferred stock 80 80 Retained earnings 2,170 1,731 Total shareholders equity 4,788 4,349 TOTAL LIABILITIES AND SHAREHOLDERS EQUITY 15,523 14,937 The accompanying notes as they relate to Ameren Missouri are an integral part of these financial statements.

9

UNION ELECTRIC COMPANY (U/b/a AMEREN MISSOURI)

STATEMENT OF CASH FLOWS (Unaudited) (In millions)

Cash Flows From Operating Activities:

Net income Adjustments to reconcile net income to net cash provided by operating activities:

Depreciation and amortization Amortization of nuclear fuel Amortization of debt issuance costs and premium/discounts Deferred income taxes and investment tax credits, net Allowance for equity funds used during construction Other Changes in assets and liabilities:

Receivables Inventories Accounts and wages payable Taxes accrued Regulatory assets and liabilities Assets, other Liabilities, other Pension and other postretirement benefits Net cash provided by operating activities Cash Flows From Investing Activities:

Capital expenditures Nuclear fuel expenditures Purchases of securities nuclear decommissioning trust fund Sales and maturities of securities nuclear decommissioning trust fund Purchase of bonds Proceeds from sale of remarketed bonds Money pool advances, net Other Net cash used in investing activities Cash Flows From Financing Activities:

Dividends on common stock Dividends on preferred stock Short-term debt, net Maturities of long-term debt Issuances of long-term debt Debt issuance costs Net cash provided by (used in) financing activities Net change in cash, cash equivalents, and restricted cash Cash, cash equivalents, and restricted cash at beginning of year Cash, cash equivalents, and restricted cash at end of period Nine Months Ended September 30, 2020 2019 442 452 68 4

(1)

(15) 13 (93)

(33)

(168) 158 (56)

(10)

(46) 449 419 56 4

(9)

(14) 10 (32) 3 (153) 148 5

(37)

(4)

(6)

(5) 709 840 (778)

(61)

(169)

I 35 (751)

(26)

(192) 184 (207) 207 (5)

(877)

(785)

(3)

(234)

(85) 465 (250)

(3) 89 (329) 450 The accompanying notes as they relate to Ameren Missouri are an integral part of these financial statements.

(4)

(6) 139 (49)

(29) 6 39 8

10 14 10

UNION ELECTRIC COMPANY (dibla AMEREN MISSOURI)

STATEMENT OF SHAREHOLDERS EQUITY (Unaudited) (In millions)

Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 CommonStock 511 511 511 511 Other Paid-in Capital 2,027 1 903 2,027 1,903 Preferred Stock 80 80 80 80 Retained Earnings:

Beginning of period 1,873 1 781 1,731 1,735 Netincome 298 301 442 449 Dividends on common stock

(150)

(250)

Dividends on preferred stock (1)

(1)

(3)

(3)

Retained earnings, end ofperiod 2,170 1,931 2,170 1,931 Total Shareholders Equity 4,788 4,425 4,788 4,425 The accompanying notes as they relate to Ameren Missouri are an integral part of these financial statements.

11

AMEREN ILLINOIS COMPANY (dibla AMEREN ILLINOIS)

STATEMENT OF INCOME (Unaudited) (In millions)

Three Months Ended Nine Months Ended September 30, September 30, 2020 2019 2020 2019 Operating Revenues:

Electric 467 452 1,346 1,305 Naturalgas 122 112 533 568 Total operating revenues 589 564 1,879 1,873 Operating Expenses:

Purchasedpower 97 101 271 284 Natural gas purchased for resale 29 25 154 195 Other operations and maintenance 197 193 578 580 Depreciation and amortization 109 102 323 304 Taxesotherthanincometaxes 33 33 107 110 Total operating expenses 465 454 1,433 1,473 Operatinglncome 124 110 446 400 Other Income, Net 17 13 45 39 lnterestCharges 39 38 116 111 Income Before Income Taxes 102 85 375 328 IncomeTaxes 25 20 93 79 Net Income 77 65 282 249 Preferred Stock Dividends

2 2

Net Income Available to Common Shareholder 77 65 280 247 The accompanying notes as they relate to Ameren Illinois are an integral part of these financial statements.

12

AMEREN ILLINOIS COMPANY (dibla AMEREN ILLINOIS)

BALANCE SHEET (Unaudited) (In millions)

September 30, December 31, 2020 2019 247 215 28 104 139 24 25 149 121 57 29 614 10,083 411 411 748 694 480 383 1,639 1,488 13,099 12,185 242 318 43 82 80 77 47 84 234 249 964 844 3,576 3,575 The accompanying notes as they relate to Ameren Illinois are an integral part of these financial statements.

15 29 31 599 10,861 ASSETS Current Assets:

Cash and cash equivalents Accounts receivable trade (less allowance for doubtful accounts of $30 and $1 0, respectively)

Accounts receivable affiliates Unbilled revenue Miscellaneous accounts receivable Inventories Current regulatory assets Other current assets Total current assets Property, Plant, and Equipment, Net Investments and Other Assets:

Goodwill Regulatory assets Other assets Total investments and other assets TOTAL ASSETS LIABILITIES AND SHAREHOLDERS EQUITY Current Liabilities:

Short-term debt Accounts and wages payable Accounts payable affiliates Customer deposits Current regulatory liabilities Other current liabilities Total current liabilities Long-term Debt, Net Deferred Credits and Other Liabilities:

Accumulated deferred income taxes and investment tax credits, net Regulatory liabilities Pension and other postretirement benefits Environmental remediation Other deferred credits and liabilities Total deferred credits and other liabilities Commitments and Contingencies (Notes 2, 8 and 9)

Shareholders Equity:

Common stock, no par value, 45.0 shares authorized 25.5 shares outstanding Other paid-in capital Preferred stock Retained earnings Total shareholders equity TOTAL LIABILITIES AND SHAREHOLDERS EQUITY 53 299 1,314 1,968 204 I 224 1,849 214 66 87 245 260 3,797 3,634 2,538 2,188 62 62 2,162 1,882 4,762 4,132 13,099 12,185 13

Cash Flows From Operating Activities:

Net income AMEREN ILLINOIS COMPANY (dibla AMEREN ILLINOIS)

STATEMENT OF CASH FLOWS (Unaudited) (In millions)

Adjustments to reconcile net income to net cash provided by operating activities:

Depreciation and amortization Amortization of debt issuance costs and premium/discounts Deferred income taxes and investment tax credits, net Other Changes in assets and liabilities:

Receivables Inventories Accounts and wages payable Taxes accrued Regulatory assets and liabilities Assets, other Liabilities, other Pension and other postretirement benefits Net cash provided by operating activities Cash Flows From Investing Activities:

Capital expenditures Other Net cash used in investing activities Cash Flows From Financing Activities:

Dividends on preferred stock Short-term debt, net Capital contributions from parent Other Net cash provided by financing activities Net change in cash, cash equivalents, and restricted cash Cash, cash equivalents and restricted cash at beginning of year Cash, cash equivalents, and restricted cash at end of period Nine Months Ended September 30, 2020 2019 282 249 322 303 9

9 72 42 8

18 (7)

(48) 14 I 47 (52)

(15)

(30) 13 (30)

(27) 515 706 (1,031)

(900)

I (3)

(1,030)

(903)

(2)

(2) 189 237 350

(1) 537 234 22 37 125 80 147 117 The accompanying notes as they relate to Ameren Illinois are an integral part of these financial statements.

(9)

(28)

(12)

(20) 11 14

AMEREN ILLINOIS COMPANY (dibla AMEREN ILLINOIS)

STATEMENT OF SHAREHOLDERS EQUITY (Unaudited) (In millions)

Common Stock Three Months Ended September 30, 2020 2019 Nine Months Ended September 30, 2020 2019 Beginning of period Net income Dividends on preferred stock Retained earnings, end of period 2,538 2,173 2,188 2,173

350

2,538 2,173 2,538 2,173 2,085 1,721 1,882 1,539 77 65 282 249

(2)

(2) 2,162 1,786 2,162 1,786 Total Shareholders Equity 4,762 4,021 4,762 4,021 The accompanying notes as they relate to Ameren Illinois are an integral part of these financial statements.

Other Paid-in Capital:

Beginning of period Capital contribution from parent Other paid-in capital, end of period Preferred Stock Retained Earnings:

62 62 62 62 15

AMEREN CORPORATION (Consolidated)

UNION ELECTRIC COMPANY (dlbla Ameren Missouri)

AMEREN ILLINOIS COMPANY (dlbla Ameren Illinois)

COMBINED NOTES TO FINANCIAL STATEMENTS (Unaudited)

September 30, 2020 NOTE I -

SUMMARY

OF SIGNIFICANT ACCOUNTING POLICIES General Ameren, headquartered in St. Louis, Missouri, is a public utility holding company whose primary assets are its equity interests in its subsidiaries.

Amerens subsidiaries are separate, independent legal entities with separate businesses, assets, and liabilities. Dividends on Amerens common stock and the payment of expenses by Ameren depend on distributions made to it by its subsidiaries. Amerens principal subsidiaries are listed below. Ameren has other subsidiaries that conduct other activities, such as providing shared services.

Union Electric Company, doing business as Ameren Missouri, operates a rate-regulated electric generation, transmission, and distribution business and a rate-regulated natural gas distribution business in Missouri.

Ameren Illinois Company, doing business as Ameren Illinois, operates rate-regulated electric transmission, electric distribution, and natural gas distribution businesses in Illinois.

ATXI operates a FERC rate-regulated electric transmission business in the MISC.

The COVID-1 9 pandemic continues to be a rapidly evolving situation. In the first nine months of 2020, we experienced a net decrease in our sales volumes, an increase in our accounts receivable balances that were past due or that were a part of a deferred payment arrangement, and a decline in our cash collections from customers. The continued effect of the COVID-1 9 pandemic on our results of operations, financial position, and liquidity in subsequent periods will depend on its severity and longevity, future regulatory or legislative actions with respect thereto, and the resulting impact on business, economic, and capital market conditions. Shelter-in-place orders began taking effect in our service territories in mid-March 2020. These orders generally required individuals to remain at home and precluded or limited the operation of businesses that were deemed nonessential. While our business operations were deemed essential and were not directly impacted by the shelter-in-place orders, approximately 65% of our workforce transitioned to remote working arrangements in mid-March 2020. In early June 2020, a small portion of our workforce began the process of returning to our work locations under a phased approach and approximately 50% of our workforce continues to work remotely. In mid-May 2020, shelter-in-place orders effective in our service territories began to be relaxed, with fewer restrictions on social activities and nonessential businesses beginning to reopen. However, certain restrictions remain in place that limit individual activities and the operation of nonessential businesses. Additional restrictions may be imposed in the future.

We continue to assess the impacts the pandemic is having on our businesses, including but not limited to impacts on our liquidity; demand for residential, commercial, and industrial electric and natural gas services; more flexible payment plans for customers; the timing and extent to which recovery of incremental costs incurred, net of savings, and forgone customer late fee revenues at Ameren Missouri is allowed by the MoPSC; changes in our ability to disconnect customers for nonpayment; bad debt expense; supply chain operations; the availability of our employees and contractors; counterparty credit; capital construction; infrastructure operations and maintenance; energy-efficiency programs; and pension valuations. While the revenues from Ameren Illinois electric distribution business, residential and small nonresidential customers ofAmeren Illinois natural gas distribution business, and Ameren Illinois and ATXIs electric transmission businesses are decoupled from changes in sales volumes, earnings at Ameren Missouri and those associated with Ameren Illinois large nonresidential natural gas customers are exposed to such changes.

Regarding uncollectible accounts receivable, Ameren Illinois electric distribution and natural gas distribution businesses have bad debt riders, which provide for recovery of bad debt write-offs, net of any subsequent recoveries. Pursuant to a June 2020 ICC order, Ameren Illinois electric bad debt rider provides for the recovery of bad debt expense in 2020. Ameren Missouri does not have a bad debt rider or regulatory tracking mechanism and its earnings are exposed to increases in bad debt expense. In October 2020, Ameren Missouri filed requests with the MoPSC for accounting authority orders related to costs incurred, net ofsavings, and forgone customer late fee revenues resulting from the COVID-19 pandemic. Our customers payment for our services has been adversely affected by the COVID-1 9 pandemic, resulting in a decrease to our cash flow from operations. As of September 30, 2020, accounts receivable balances that were 30 days or greater past due or that were a part of a deferred payment arrangement represented 26%, 18%, and 35%, or $151 million, $49 million, and $102 million, ofAmerens, Ameren Missouris, and Ameren Illinois customer trade receivables before allowance for doubtful accounts, respectively. As of September 30, 201 9, these percentages were 13%, 9%, and 18%, or $65 million, $23 million, and $42 million, forAmeren, Ameren Missouri, and Ameren Illinois, respectively. For information regarding Ameren Missouris and Ameren Illinois suspension and subsequent reinstatement of customer disconnections and late fee charges for nonpayment and Ameren Missouris requests for accounting authority orders related to the COVID-19 pandemic, see Note 2 Rate and Regulatory Matters below.

16

The Coronavirus Aid, Relief, and Economic Security Act is a federal law enacted in March 2020. Provisions in the act include temporary changes to the utilization of net operating losses, deferral of the payment of the employer portion of Social Security taxes, and additional funding for customer energy assistance, among other things. As of September 30, 2020, the implementation of the act by the Ameren Companies had no material impact to their financial statements.

Amerens financial statements are prepared on a consolidated basis and therefore include the accounts of its majority-owned subsidiaries. All intercompany transactions have been eliminated, except as disclosed in Note 8 Related-party Transactions. Ameren Missouri and Ameren Illinois have no subsidiaries. All tabular dollar amounts are in millions, unless otherwise indicated.

Our accounting policies conform to GAAP. Our financial statements reflect all adjustments (which include normal, recurring adjustments) that are necessary, in our opinion, for a fair statement of our results. The preparation of financial statements in conformity with GAAP requires management to make certain estimates and assumptions. Such estimates and assumptions affect reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the dates of financial statements, and the reported amounts of revenues and expenses during the reported periods. Actual results could differ from those estimates. The results of operations of an interim period may not give a true indication of results that may be expected for a full year. These financial statements should be read in conjunction with the financial statements and accompanying notes included in the Form 10-K.

Variable Interest Entities As of September 30, 2020, Ameren and Ameren Missouri had interests in unconsolidated variable interest entities that were established to construct wind generation facilities and, ultimately, sell those constructed facilities to Ameren Missouri. Neither Ameren nor Ameren Missouri are the primary beneficiary of these variable interest entities because neither has the power to direct matters that most significantly affect the entities activities, which include designing, financing, and constructing the wind generation facilities. As a result, these variable interest entities have not been consolidated. As of September 30, 2020, the maximum exposure to loss related to these variable interest entities was approximately $18 million, which primarily represents due diligence and legal costs incurred by Ameren Missouri associated with the acquisitions. The risk of a loss was assessed to be remote and, accordingly, Ameren and Ameren Missouri have not recognized a liability associated with any portion ofthe maximum exposure to loss. See Note 2 Rate and Regulatory Matters for additional information on the agreements to acquire these wind generation facilities.

As of September 30, 2020, and December 31

, 2019, Ameren had unconsolidated variable interests as a limited partner in various equity method investments, totaling $34 million and $28 million, respectively, included in Other assets on Amerens consolidated balance sheet. Ameren is not the primary beneficiary of these investments because it does not have the power to direct matters that most significantly affect the activities of these variable interest entities. As of September 30, 2020, the maximum exposure to loss related to these variable interests is limited to the investment in these partnerships of $34 million plus associated outstanding funding commitments of $37 million.

Company-owned Life Insurance Ameren and Ameren Illinois have company-owned life insurance, which is recorded at the net cash surrender value. The net cash surrender value is the amount that can be realized under the insurance policies at the balance sheet date. As of September 30, 2020, the cash surrender value of company-owned life insurance at Ameren and Ameren Illinois was $260 million (December 31

, 2019

$264 million) and $1 14 million (December 31, 2019

$123 million), respectively, while total borrowings againstthe policies were $107 million (December 31

, 2019

$114 million) at both Ameren and Ameren Illinois. Ameren and Ameren Illinois have the right to offset the borrowings against the cash surrender value of the policies and, consequently, present the net asset in Other assets on their respective balance sheets.

Accounting and Reporting Developments See Note 1 Summary of Significant Accounting Policies under Part II, Item 8, of the Form 1 0-K for additional information about authoritative accounting guidance relating to defined benefit plan disclosures that will be effective for the Ameren Companies in the fourth quarter of 2020.

Measurement of Credit Losses on Financial Instruments On January 1

, 2020, the Ameren Companies adopted authoritative accounting guidance that requires credit losses on most financial assets carried at amortized cost and off-balance sheet credit exposures, such as financial guarantees or loan commitments, to be measured using a current expected credit loss (CECL) model. The guidance requires an entity to measure expected credit losses using relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectibility of the reported amount. In addition, the guidance made certain changes to the impairment model applicable to available-for-sale debt securities, such as requiring credit losses to be presented as an allowance rather than a write-down on impaired debt securities for which there is neither an intent nor a more-likely-than-not requirement to sell. Our adoption of this guidance did not have a material impact on the Ameren Companies 17

financial statements and did not result in a cumulative effect adjustment to retained earnings as of the adoption date. See Note 1 3 Supplemental Information for additional information regarding credit losses on accounts receivable.

NOTE 2 - RATE AND REGULATORY MATTERS Below is a summary of updates to significant regulatory proceedings and related legal proceedings. See Note 2 Rate and Regulatory Matters under Part II, Item 8, of the Form I 0-K for additional information and a summary of our regulatory frameworks. We are unable to predict the ultimate outcome of these mailers, the timing of the final decisions of the various agencies and courts, or the impact on our results of operations, financial position, or liquidity.

Missouri March 2020 MoPSC Electric Rate Order In March 2020, the MoPSC issued an order in Ameren Missouris July 2019 electric service regulatory rate review, approving nonunanimous stipulation and agreements. The order resulted in a decrease of $32 million to Ameren Missouris annual revenue requirement for electric retail service, which reflects infrastructure investments as of December 31

, 201 9. The order also provided for the continued use of the FAC and trackers for pension and postretirement benefits, uncertain income tax positions, and certain excess deferred income taxes that the MoPSC previously authorized in earlier electric rate orders. The order reduced the annualized base level of net energy costs pursuant to the FAC by approximately

$1 1 5 million from the base level established in the MoPSCs March 2017 electric rate order. The order also changed the annualized regulatory asset and liability amortization amounts and the base level of expenses for regulatory tracking mechanisms. On an annualized basis, these changes reflect approximately $20 million of increased revenues and approximate decreases in purchased power expenses of $1 5 million, other operating and maintenance expenses of $60 million, and income tax expenses of $20 million. Additionally, the annual revenue requirement incorporated increases of approximately $50 million for the reduction in sales volumes resulting from MEEIA programs and approximately $50 million of depreciation and amortization expense for amounts previously deferred under PISA. The increase in the annual revenue requirement related to the MEEIA programs is seasonally weighted to the summer. One of the stipulation and agreements approved by the MoPSCs March 2020 order states that the net impact of the revenue and expense changes noted above reflects a 9.4% to 9.8% ROE on an unspecified percent of common equity applicable to rate base. In addition, the order required Ameren Missouri to donate $8 million to low-income assistance programs, which was reflected in results of operations in the first quarter of 2020. The new rates, base level of expenses, and amortizations became effective on April 1, 2020. In April 2020, the MoPSC issued another order in Ameren Missouris July 2019 electric service regulatory rate review, reaffirming the existing percentage of net energy cost variances allowed to be recovered or refunded under the FAC.

Wind Generation Facilities In 201 9, Ameren Missouri entered into a build-transfer agreement to acquire, after construction, an up-to 300-megawatt wind generation facility.

In 201 8, Ameren Missouri entered into a build-transfer agreement to acquire, after construction, an up-to 400-megawatt wind generation facility.

These two agreements are subject to customary contract terms and conditions. The two build-transfer acquisitions collectively represent $1.2 billion of capital expenditures and would support Ameren Missouris compliance with the Missouri renewable energy standard. Both acquisitions have received all regulatory approvals, and both projects have received all applicable zoning approvals, have entered into RTO interconnection agreements, and are under construction.

In 2020, the developers of the wind generation facilities received notices from the wind turbine supplier to each facility, and the developer of the up-to 300-megawatt project received a notice from the construction contractor, of changes in supply and/or construction activities resulting from the COVID-19 pandemic. There have been changes to the schedules for both projects, particularly with regard to wind turbine deliveries. During the third quarter of 2020, all remaining wind turbine deliveries for the up-to 400-megawatt project were completed. Based on the construction schedule, Ameren Missouri expects this project to be placed in-service by the end of 2020. At this time, due to manufacturing, shipping, and other supply chain issues in 2020, and, based on an updated construction schedule from the developer, Ameren Missouri expects the up-to 300-megawatt project to be partially placed in-service by the end of 2020, and the remaining portion of the project, representing approximately $200 million of investment, to be placed in-service in the first quarter of 2021

. Ameren Missouri and the developer of the up-to 300-megawatt project continue to monitor the impact to this projects schedule. In May 2020, the IRS issued guidance that extended the in-service date criteria to December 31

, 2021

, for qualifying for federal production tax credits. As a result of this extension, Ameren does not anticipate that delays in the completion of the wind generation facilities will affect Amerens ability to realize anticipated federal production tax credits.

MEEIA In August 2020, the MoPSC issued an order approving a unanimous stipulation and agreement with respect to the 2022 program year of Ameren Missouris six-year MEEIA 2019 program. The order established performance incentives that would provide Ameren Missouri an opportunity to earn additional revenues, including $1 I million if Ameren Missouri achieves certain energy-efficiency goals during the 2022 18

program year and an additional $1 million ifAmeren Missouri exceeds its targeted energy-efficiency goals. Ameren Missouri intends to invest

$70 million in energy-efficiency programs during the 2022 program year. The August 2020 order also approved Ameren Missouris energy savings results for the first year of the MEEIA 201 9 program. As a result of this order and in accordance with revenue recognition guidance, Ameren Missouri recognized revenues of $6 million in the third quarter of 2020. As a result of MoPSC orders issued in September 2017, October 2018, January 201 9, and September 201 9 related to performance incentives for the MEEIA 2013 and MEEIA 2016 programs, and in accordance with revenue recognition guidance, Ameren Missouri recognized revenues of $38 million during the first nine months of 2019.

Requests forAccounting Authority Orders Related to COVID-19 Pandemic Costs Ameren Missouri suspended disconnections for customer nonpayment and charging late fees in mid-March 2020, and resumed those activities for commercial and industrial customers in mid-July 2020 and residential customers in early August 2020. In October 2020, Ameren Missouri filed requests with the MoPSC for accounting authority orders related to its electric and natural gas services. The orders would allow Ameren Missouri to accumulate certain costs incurred related to the COVID-19 pandemic and forgone customer late fee revenues from March 2020 to June 2021, for potential recovery in future electric and natural gas service regulatory rate reviews. These costs would be net of any cost savings Ameren Missouri realizes as a result ofthe COVID-19 pandemic. The orders would also allow Ameren Missouri to accumulate bad debtwrite-offs incurred from March 2020 to September 2021 due to the COVID-19 pandemic, for potential recovery in future electric and natural gas service regulatory rate reviews.

The requests include an estimated $9 million of costs incurred, net of savings, and forgone customer late fee revenues related to the COVID-19 pandemic from March 2020 through September 2020. The requests did not seek accumulation for potential recovery of forgone revenues associated with decreased sales volumes related to the COVID-19 pandemic. The MoPSC is under no deadline to issue orders, and Ameren Missouri cannot predict the ultimate outcome of these regulatory proceedings.

Illinois Electric Distribution Service Rates In April 2020, Ameren Illinois filed its annual electric distribution service formula rate update with the ICC, requesting a reduction of $45 million in its rates. This update reflects a decrease to the annual formula rate based on 2019 actual costs, a decrease to include the 2019 revenue requirement reconciliation adjustment, and a decrease for the conclusion of the 201 8 revenue requirement reconciliation adjustment, which will be fully collected from customers in 2020, consistent with the ICCs December 2019 annual update filing order. It also reflects an increase based on expected net plant additions for 2020. In September 2020, the ICC staff submitted its revised calculation of the revenue requirement included in Ameren Illinois update filing, recommending a $49 million decrease in Ameren Illinois electric distribution service rates. An ICC decision in this proceeding is expected by December 2020, with new rates effective January 2021.

Electric Customer Energy-Efficiency Investments In May 2020, Ameren Illinois filed its annual electric customer energy-efficiency formula rate update to increase its rates by $7 million with the ICC. In August 2020, the ICC staff submitted a calculation of the revenue requirement included in Ameren Illinois filing, recommending an amount comparable to that included in Ameren Illinois filing. An ICC decision in this proceeding is expected by December 2020, with new rates effective January 2021.

2020 Natural Gas Delivery Service Regulatoty Rate Review In February 2020, Ameren Illinois filed a request with the ICC seeking approval to increase its annual revenues for natural gas delivery service.

In September 2020, Ameren Illinois filed a revised request seeking to increase its annual revenues for natural gas delivery service by $97 million, which includes an estimated $46 million of annual revenues that would otherwise be recovered under the QIP and other riders. The request is based on a 10.5% ROE, a capital structure composed of 54.1% common equity, and a rate base of $2.1 billion. Ameren Illinois used a 2021 future test year in this proceeding. In October 2020, the ICC staff recommended an increase to annual revenues for natural gas delivery service of $69 million, based on a 9.3% ROE, a capital structure composed of 50.4% common equity, and a rate base of $2.1 billion. A decision by the ICC in this proceeding is required by January 2021

, with new rates expected to be effective in February 2021

. Ameren Illinois cannot predict the level of any delivery service rate change the ICC may approve, nor whether any rate change that may eventually be approved will be sufficient to enable Ameren Illinois to earn a reasonable return on investments when the rate changes go into effect.

QIP Reconciliation Hearing In March 2019, Ameren Illinois filed its annual request with the ICC for a reconciliation hearing to determine the accuracy and prudence of natural gas capital investments recovered under the QIP rider during 2018. In November 2019, the Illinois Attorney Generals office challenged the recovery of capital investments, among other things, that were made during 201 8, alleging that the amount of investments is excessive based on a comparison to historical investment levels. The Illinois Attorney Generals office is not alleging project imprudence or that the investments do not qualify for recovery. In March 2020, the ICC staff filed testimony that supports the prudence and reasonableness 19

ofthe capital investments made during 2018. Ameren Illinois 2018 QIP rate recovery request under review by the ICC is within the rate increase limitations allowed by law. The ICC is under no deadline to issue an order in this proceeding.

Service Disconnection Moratorium Proceeding In March 2020, the ICC issued an order requiring all Illinois electric distribution and natural gas utilities to suspend disconnections and late fees for customer nonpayment, on an interim basis, effective March 1 8, 2020. Pursuant to an ICC order issued in June 2020 and a voluntary extension of the suspension of residential disconnections, Ameren Illinois resumed disconnection activities for commercial and industrial customers for nonpayment in early August 2020 and residential customers in mid-September 2020, with the exception of residential customers classified as low income, expressing a financial hardship, or relying on medical equipment. Disconnections for nonpayment for these residential customers are expected to begin in April 2021

, which is after the annual winter moratorium period on disconnections from December 1

, 2020 to March 31

, 2021.

Ameren Illinois also resumed charging late fees to all customers in late July 2020. The June 2020 order requires Ameren Illinois to implement more flexible credit and collection practices, on a temporary basis, including longer deferred payment arrangements, extending to 24 months in certain cases, and programs to provide financial assistance to customers. In addition, the order allows Ameren Illinois to recover up to $8 million in costs incurred related to the financial assistance programs. These costs will be deferred as regulatory assets and the portion associated with Ameren Illinois electric distribution business will be recovered through its bad debt rider and the portion associated with its natural gas distribution business will be recovered through a special purpose rider established by the order. The order also allows Ameren Illinois to recover forgone customer late fees and costs incurred related to the COVID-19 pandemic. The portion ofthese forgone late fees and costs associated with Ameren Illinois electric distribution business will be recovered through formula rates and the portion associated with its natural gas distribution business will be recovered through the special purpose rider. In addition, the order allows Ameren Illinois electric distribution business to recover bad debt expense, instead of write-offs net of subsequent recoveries, through its bad debt rider until the end of 2020.

Federal Transmission Formula Rate Revisions In February 2020, the MISO, on behalf of Ameren Missouri, Ameren Illinois, and ATXI, filed requests with the FERC to revise each companys transmission formula rate calculations with respect to calculation inputs for materials and supplies. In May 2020, the FERC issued orders approving the revisions prospectively. In addition, the FERC declined to order refunds for earlier periods, as requested by intervenors in Ameren Illinois filing, but directed its audit staff to review historical rate recovery in connection with an ongoing FERC audit. This review could lead the FERC to ultimately require refunds for periods prior to 2019. In June 2020, Ameren Missouri, Ameren Illinois, and ATXI filed requests for rehearing arguing, among other things, the revisions should be applied retrospectively to include the period January 1

, 2019, to June 1

, 2020, and that the FERC should not require refunds for periods prior to 2019. In July 2020, the FERC denied the rehearing requests without addressing the issues raised. In July 2020, Ameren Missouri, Ameren Illinois, and ATXI filed an appeal of the July 2020 rehearing denials to the United States Court of Appeals for the District of Columbia Circuit, which is under no deadline to address the appeal. In October 2020, the FERC issued an order reaffirming its May 2020 order and denying the arguments raised in the rehearing requests filed by Ameren Missouri, Ameren Illinois, and ATXI. Pursuant to the May 2020 order, in the second quarter of 2020, Ameren and Ameren Illinois recorded a $2 million reduction to revenue for the period of January 201 9 through May 2020. Regardless of the outcome of the appeal, the impacts of the May 2020 and October 2020 orders are not expected to be material to Amerens, Ameren Missouris, or Ameren Illinois results of operations, financial position, or liquidity.

FERC Complaint Cases In November 2013, a customer group filed a complaint case with the FERC seeking a reduction in the allowed base ROE for FERC-regulated transmission rate base underthe MlSOtarifffrom 12.38%to 9.15%. In September2016, the FERC issued an order inthe November2013 complaint case, which lowered the allowed base ROE to 10.32%, or a 10.82% total allowed ROE with the inclusion of a 50 basis point incentive adder for participation in an RTO, that was effective from late September 2016 forward. The September 2016 order also required refunds for the period November 201 3 to February 201 5, which were paid in 201 7. With the maximum FERC-allowed refund period for the November2013 complaint case ending in February 2015, another customer complaint case was filed in February 2015, seeking a further reduction in the allowed base ROE for the period of February 2015 to May 2016. In November 2019, the FERC issued an order addressing the November 2013 complaint case, which setthe allowed base ROE at 9.88%, superseding the 10.32% previously ordered, and required refunds, with interest, for the periods November 2013 to February 2015 and from late September 2016 forward. The order also dismissed the February 2015 complaint case. In December 2019, the MISO transmission owners, including Ameren Missouri, Ameren Illinois, and ATXI, filed requests for rehearing with the FERC.

Additionally, in December 2019, various parties filed requests for rehearing with the FERC, challenging the dismissal ofthe February 2015 complaint case. In May 2020, the FERC issued an order addressing the requests for rehearing, which setthe allowed base ROE at 10.02%, superseding the 9.88% previously ordered, and required refunds, with interest, for the periods November 2013 to February 2015 and from late September 2016 forward. The May 2020 order also denied rehearing of the FERCs dismissal ofthe February 201 5 complaint case. In June 2020, various parties filed requests for rehearing with the FERC, challenging the new 20

ROE methodology established by the May 2020 order. In July 2020, the FERC denied the rehearing requests without addressing the issues raised, and indicated it will address the requests for rehearing in a future order. Also in July 2020, Ameren Missouri, Ameren Illinois, and ATXI filed an appeal of the May 2020 order to the United States Court of Appeals for the District of Columbia Circuit challenging the refunds required for the period from September 2016 to May 2020. The court is under no deadline to address the appeal.

As a result of the May 2020 order, which increased the FERC-allowed base ROE from 9.88% to 1 0.02% for the periods November 201 3 to February 2015 and late September 2016 forward, Ameren and Ameren Illinois recognized income of $13 million and $7 million, respectively, during the second quarter of 2020. As of September 30, 2020, Ameren and Ameren Illinois had recorded current regulatory liabilities of $1 5 million and $7 million, respectively, to reflect the expected refunds, including interest, associated with the allowed base ROE set by the May 2020 order in the November 2013 complaint case. The increase in the FERC-allowed base ROE resulting from the May 2020 order is not material to Ameren Missouris results of operations, financial position, or liquidity.

In March 2019, the FERC issued separate Notices of Inquiry regarding its allowed base ROE policy and its transmission incentives policy. The Notice of Inquiry addressing the FERCs base ROE policy, among other things, broadened the ability to comment on the new methodology beyond electric utilities that are participants in the complaint cases. The transmission incentives Notice of Inquiry was open for comment on the FERCs transmission incentive policy, including incentive adders to the base ROE. In March 2020, the FERC issued a Notice of Proposed Rulemaking on its transmission incentives policy, which addressed many of the issues in the Notice of Inquiry on transmission incentives. The Notice of Proposed Rulemaking included an increased incentive in the allowed base ROE for participation in an RTO to 100 basis points from the current 50 basis points and revised the parameters for awarding incentives, while limiting the overall incentives to a cap of 250 basis points, among other things. Initial comments were due by July 2020. While the FERC has not formally terminated the Notice of Inquiry regarding its transmission incentives policy, Ameren does not expect further actions relating to it. Ameren is unable to predict the ultimate impact of the Notice of Inquiry regarding its allowed base ROE policy or the Notice of Proposed Rulemaking at this time.

NOTE 3 SHORT-TERM DEBT AND LIQUIDITY The liquidity needs of the Ameren Companies are typically supported through the use of available cash, drawings under committed credit agreements, commercial paper issuances, and, in the case ofAmeren Missouri and Ameren Illinois, short-term affiliate borrowings. See Note 4 Short-term Debt and Liquidity under Part II, Item 8, in the Form 10-K for a description of our indebtedness provisions and other covenants as well as a description of money pool arrangements.

Short-Term Borrowings The Missouri Credit Agreement and the Illinois Credit Agreement are available to support issuances under Ameren (parent)s, Ameren Missouris, and Ameren Illinois commercial paper programs, respectively, subject to borrowing sublimits, and the issuance of letters of credit. As of September 30, 2020, based on commercial paper outstanding and letters of credit issued under the Credit Agreements, along with cash and cash equivalents, the net liquidity available to Ameren (parent), Ameren Missouri, and Ameren Illinois, collectively, was $2.0 billion. The Ameren Companies were in compliance with the covenants in their Credit Agreements as of September 30, 2020. As of September 30, 2020, the ratios of consolidated indebtedness to consolidated total capitalization, calculated in accordance with the provisions of the Credit Agreements, were 55%,

48%, and 45% for Ameren, Ameren Missouri, and Ameren Illinois, respectively.

The following table presents commercial paper outstanding, net of issuance discounts, as of September 30, 2020, and December 31

, 2019.

There were no borrowings outstanding under the Credit Agreements as of September 30, 2020, or December 31

, 2019.

Ameren (parent)

September 30, 2020 December 31, 2019 Ameren Missouri 30 153 Amecen Illinois 234 Ameren consolidated 242 53 272 440 21

The following table summarizes the activity and relevant interest rates for Ameren (parent)s, Ameren Missouris, and Ameren Illinois commercial paper issuances and borrowings under the Credit Agreements in the aggregate for the nine months ended September 30, 2020 and 2019:

Ameren Ameren Ameren Ameren (parent)

Missouri Illinois Consolidated 2020 Average daily amount outstanding 62 142 53 257 Weighted-average interest rate 2.04 %

1.76 %

tb 1.70 Peak amount outstanding during period(a) 425 573 243 908 Peak interest rate 3.30 %

5.05 % (b) 3.40 %

5.05

% (b) 2019 Average daily amount outstanding 532 141 147 821 Weighted-average interest rate 2.70 %

273 %

2.58 %

2.68 Peak amountoutstanding during periodfa) 651 549 310 1,113 Peak interest rate 3.80 %

2.97 %

5.00 % (C) 5.00

% (c)

(a)

The timing of peak outstanding commercial paper issuances and borrowings under the Credit Agreements varies by company. Therefore, the sum of individual company peak amounts may not equal the Ameren consolidated peak for the period.

(b)

Amerens and Ameren Missouris peak interest rate was affected by temporary disruptions in the commercial paper market in the first quarter of 2020.

(c)

Amerens and Ameren Illinois peak interest rate was affected by temporary disruptions in the commercial paper market in the third quarter of 2019.

Money Pools Ameren has money pool agreements with and among its subsidiaries to coordinate and provide for certain short-term cash and working capital requirements. The average interest rate for borrowings under the utility money pool for the three and nine months ended September 30, 2020, was 0.10% and 0.81%, respectively (2019 2.40% and 2.67%, respectively). See Note 8 Related-party Transactions forthe amount of interest income and expense from the utility money pool arrangements recorded by Ameren Missouri and Ameren Illinois for the three and nine months ended September 30, 2020 and 2019.

NOTE 4 - LONG-TERM DEBT AND EQUITY FINANCINGS Ameren For the three and nine months ended September 30, 2020, Ameren issued a total of 0.1 million and 0.5 million shares of common stock, respectively, under its DRPIus and 401(k) plan, and received proceeds of $10 million and $37 million, respectively. In addition, in the first quarter of 2020, Ameren issued 0.5 million shares of common stock valued at $38 million upon the vesting of stock-based compensation.

In August 201 9, Ameren entered into a forward sale agreement with a counterparty relating to 7.5 million shares of common stock. The forward sale agreement will be physically settled unless Ameren elects to settle in cash or to net share settle. At September 30, 2020, Ameren could have settled the forward sale agreement with physical delivery of 7.5 million shares of common stock to the counterparty in exchange for $543 million.

The forward sale agreement could also have been settled at September 30, 2020, with delivery of approximately $54 million or 0.7 million shares of common stock to the counterparty, ifAmeren had elected to net cash or net share settle, respectively. For additional information about the forward sale agreement, see Note 5 Long-Term Debt and Equity Financings under Part II, Item 8, in the Form 10-K.

In April 2020, Ameren (parent) issued $800 million of 3.50% senior unsecured notes due January 2031

, with interest payable semiannually on January 1 5 and July 1 5 of each year, beginning July 1 5, 2020. Ameren received net proceeds of $793 million, which were used for general corporate purposes, including to repay outstanding short-term debt, and were used to fund the repayment of Amerens $350 million of 2.70% senior unsecured notes, which were redeemed at par plus accrued interest in October 2020.

In October 2020, Ameren, Ameren Missouri, and Ameren Illinois filed a Form 5-3 shelf registration statement with the SEC, registering the issuance of an unspecified amount of certain types of securities. This registration statement became effective immediately upon filing and expires in October 2023.

Ameren Missouri In March 2020, Ameren Missouri issued $465 million of 2.95% first mortgage bonds due March 2030, with interest payable semiannually on March 15 and September 15 ofeach year, beginning September 15, 2020. Ameren Missouri received net proceeds of$462 million, which were used to repay outstanding short-term debt, including short-term debt that Ameren Missouri incurred in connection with the repayment of $85 million of its 5.00% senior secured notes that matured in February 2020.

22

In October 2020, Ameren Missouri issued $550 million of 2.625% first mortgage bonds due March 2051 with interest payable semiannually on March 15 and September 1 5 of each year, beginning March 1 5, 2021

. The bonds were issued as green bonds; therefore, the proceeds will be used for eligible green projects. Ameren Missouri received net proceeds of $543 million, which are expected to be used to partially finance the acquisition of two wind generation facilities. See Note 2 Rate and Regulatory Matters for information about the wind generation facilities.

Ameren Illinois Ameren Illinois received cash capital contributions totaling $350 million from Ameren (parent) during the nine months ended September 30, 2020.

Indenture Provisions and Other Covenants See Note 5 Long-Term Debt and Equity Financings under Part II, Item 8, in the Form I 0-K for a description of our indenture provisions and other covenants, as well as restrictions on the payment of dividends. At September 30, 2020, the Ameren Companies were in compliance with the provisions and covenants contained in their indentures and articles of incorporation, as applicable, and ATXI was in compliance with the provisions and covenants contained in its note purchase agreement.

Off-balance-sheet Arrangements At September 30, 2020, none of the Ameren Companies had any significant off-balance-sheet financing arrangements, other than the forward sale agreement relating to common stock and variable interest entities. See Note 1 Summary of Significant Accounting Policies for further detail concerning variable interest entities.

NOTE 5 OTHER INCOME, NET The following table presents the components of Other Income, Net in the Ameren Companies statements of income for the three and nine months ended September 30, 2020 and 2019:

Three Months Nine Months 2020 2019 2020 2019 Ameren:

Allowance for equity funds used during construction 12 7

25 20 Interest income on industrial development revenue bonds 7

6 19 19 Other interest income

2 2

6 Non-service cost components of net periodic benefit income(a) 32 23 85 67 Miscellaneous income I

2 10 6

Donations

(1)

(14) (b)

(8)

Miscellaneous expense (4)

(5)

(10)

(11)

Total Other Income, Net 48 34 117 99 Ameren Missouri:

Allowance for equity funds used during construction 7

6 15 14 Interest income on industrial development revenue bonds 7

6 19 19 Non-service cost components of net periodic benefit income(a)

I 3 4

32 13 Miscellaneous income I

2 3

4 Donations

(1)

(9) (b)

(3)

Miscellaneous expense (2)

(2)

(5)

(4)

Total Other Income, Net 26 15 55 43 Ameren Illinois:

Allowance for equity funds used during construction 5

1 10 6

Interestincome

I 2

5 Non-service cost components of net periodic benefit income 12 12 36 36 Miscellaneous income I

1 6

3 Donations

(5)

(5)

Miscellaneous expense (1)

(2)

(4)

(6)

Total Other Income, Net 17 13 45 39 (a)

For the three and nine months ended September 30, 2020, the non-service cost components of net periodic benefit income were adjusted by amounts deferred of $(3) million and less than $(1 ) million, respectively, due to a regulatory tracking mechanism for the difference between the level of such costs incurred by Ameren Missouri under GAAP and the level of such costs included in rates. The deferral was $7 million and $22 million for three and nine months ended September 30, 201 9, respectively.

(b)

Includes $8 million pursuant to Ameren Missouris March 2020 electric rate order. See Note 2 Rate and Regulatory Matters for additional information.

23

NOTE 6 DERIVATIVE FINANCIAL INSTRUMENTS We use derivatives to manage the risk of changes in market prices for natural gas, power and uranium, as well as the risk of changes in tail transportation surcharges through fuel oil hedges. Such price fluctuations may cause the following:

an unrealized appreciation or depreciation of our contracted commitments to purchase or sell when purchase or sale prices under the commitments are compared with current commodity prices; market values of natural gas and uranium inventories that differ from the cost of those commodities in inventory; actual cash outlays for the purchase of these commodities that differ from anticipated cash outlays; and actual off-system sales revenues that differ from anticipated revenues The derivatives that we use to hedge these risks are governed by our risk management policies for forward contracts, futures, options, and swaps. Our net positions are continually assessed within our structured hedging programs to determine whether new or offsetting transactions are required. The goal of the hedging program is generally to mitigate financial risks while ensuring that sufficient volumes are available to meet out requirements. Contracts we enter into as part of our risk management program may be settled financially, settled by physical delivery, or net settled with the counterparty.

All contracts considered to be derivative instruments are required to be recorded on the balance sheet at their fair values, unless the NPNS exception applies. Many of our physical contracts, such as our purchased power contracts, qualify for the NPNS exception to derivative accounting rules. The revenue or expense on NPNS contracts is recognized at the contract price upon physical delivery. The following disclosures exclude NPNS contracts and other non-derivative commodity contracts that are accounted for under the accrual method of accounting.

If we determine that a contract meets the definition of a derivative and is not eligible for the NPNS exception, we review the contract to determine whether the resulting gains or losses qualify for regulatory deferral. Derivative contracts that qualify for regulatory deferral are recorded at fair value, with changes in fair value recorded as regulatory assets or liabilities in the period in which the change occurs. We believe derivative losses and gains deferred as regulatory assets and liabilities are probable of recovery, or tefund, through future rates charged to customers.

Regulatory assets and liabilities are amortized to operating income as related losses and gains are reflected in rates charged to customers.

Therefore, gains and losses on these derivatives have no effect on operating income. As of September 30, 2020, and December 31

, 201 9, all contracts that met the definition of a derivative and were not eligible for the NPNS exception received regulatory deferral. Cash flows for all derivative financial instruments are classified in cash flows from operating activities.

The following table presents open gross commodity contract volumes by commodity type for derivative assets and liabilities as of September 30, 2020, and December 31, 201 9. As of September 30, 2020, these contracts extended through Octobet 2023, October 2025, May 2032 and March 2023 for fuel oils, natural gas, power and uranium, respectively Quantity (in millions except as indicated)

September 30, 2020 December 31, 2019 Ameren Ameren Commodity Missouri Ameren Illinois Ameren Missouri Ameren Illinois Ameren Fuel oils (in gallons) 44

44 58 58 Natural gas (in mmbtu) 32 123 155 20 136 156 Power (in megawatthours) 6 7

13 5

7 12 Uranium (pounds in thousands) 365

365 565

565 24

The following table presents the carrying value and balance sheet location of all derivative commodity contracts, none of which were designated as hedging instruments, as of September 30, 2020, and December 31, 2019:

September 30, 2020 December 31, 2019 Ameren Ameren Ameren Ameren Balance Sheet Location Missouri Illinois Ameren Missouri Illinois Ameren Fuel oils Other current assets 2

2 4

4 Other assets

2

2 Natural gas Other current assets 2

1 0 1 2

3 3

Other assets 2

4 6

I 1

Power Other current assets I 2

I 2 1 4

14 Other assets I

I 2

2 Totalassets 19 14 33 22 4

26 Fuel oils Other current liabilities 14

14 4

4 Other deferred credits and liabilities 6

6 3

3 Natural gas Other current liabilities

2 2

1 12 13 Other deferred credits and liabilities

I I

I 6

7 Power Other current liabilities 6

16 22 2

17 19 Other deferred credits and liabilities 4

1 97 201 1

207 208 Uranium Other deferred credits and liabilities

I

I Total liabilities 30 216 246 13 242 255 The Ameren Companies elect to present the fair value amounts of derivative assets and derivative liabilities subject to an enforceable master netting arrangement or similar agreement at the gross amounts on the balance sheet. However, if the gross amounts recognized on the balance sheet were netted with derivative instruments and cash collateral received or posted, the net amounts would not be materially different from the gross amounts at September 30, 2020, and December 31

, 2019.

Credit Risk In determining our concentrations of credit risk related to derivative instruments, we review our individual counterparties and categorize each counterparty into groupings according to the primary business in which each engages. As of September 30, 2020, if counterparty groups were to fail completely to perform on contracts, the Ameren Companies maximum exposure related to derivative assets would have been immaterial with or without consideration of the application of master netting arrangements or similar agreements and collateral held.

Certain of our derivative instruments contain collateral provisions tied to the Ameren Companies credit ratings. If our credit ratings were downgraded below investment grade, or if a counterparty with reasonable grounds for uncertainty regarding our ability to satisfy an obligation requested adequate assurance of performance, additional collateral postings might be required. The additional collateral required is the net liability position allowed under master netting arrangements or similar agreements, assuming (1 ) the credit risk-related contingent features underlying these arrangements were triggered and (2) those counterparties with rights to do so requested collateral. As of September 30, 2020, the aggregate fair value of derivative instruments with credit risk-related contingent features in a gross liability position, the cash collateral posted, and the aggregate amount of additional collateral that counterparties could require were each immaterial to Ameren, Ameren Missouri, and Ameren Illinois.

NOTE 7 - FAIR VALUE MEASUREMENTS Fair value is defined as the price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Fair value measurements are classified in three levels based on the fair value hierarchy as defined by GAAP. See Note 8 Fair Value Measurements under Part II, Item 8, ofthe Form 10-K for information related to hierarchy levels and valuation techniques.

We consider nonperformance risk in our valuation of derivative instruments by analyzing our own credit standing and the credit standing of our counterparties, and by considering any credit enhancements (e.g., collateral). Included in our valuation, and based on current market conditions, is a valuation adjustment for counterparty default derived from market data such as the price of credit default swaps, bond yields, and credit ratings. No material gains or losses related to valuation adjustments for counterparty default risk were recorded at Ameren, Ameren Missouri, or Ameren Illinois in the three and nine months ended September 30, 2020 or 201 9. At September 30, 2020, and December 31

, 2019, the counterparty default risk valuation adjustment related to derivative contracts was immaterial for Ameren, Ameren Missouri, and Ameren Illinois.

25

The following table sets forth, by level within the fair value hierarchy, our assets and liabilities measured at fair value on a recurring basis as of September30, 2020, and December31, 2019:

September 30, 2020 December 31, 2019 Level I Level 2 Level 3 Total Level I Level 2 Level 3 Total Assets:

Ameren Missouri Derivative assets commodity contracts:

Fuel oils 2 $

2 6 $

6 Natural gas

4

4

Power I

12 13

2 14 16 Total derivative assets commodity contracts I $

4 $

14 $

19 2 $

20 $

22 604 $

604 569 $

569

112

112

107

107

ff6

116

93

93

66

66

73

73 Total nuclear decommissioning trust fund 604 $

294 $

898 (a) 569 $

273 $

842 (a)

Total Ameren Missouri 605 $

298 $

14 $

917 569 $

275 $

20 $

864 Ameren Illinois Derivative assets commodity contracts:

Naturalgas 9 $

5 $

14 1

3 $

4 Ameren Derivative assets commodity contracts(b(

I $

13 $

19 $

33 3 $

23 $

26 Nuclear decommissioning trust fund(c) 604 294

898 (a) 569 273

842 (a)

Total Ameren 605 $

307 $

f9 $

931 569 $

276 $

23 $

868 Liabilities:

Ameren Missouri Derivative liabilities commodity contracts:

Fueloils 13 $

7 $

20 I

6 $

7 Natural gas

2

2 Power 8

2 10

2 1

3 uranium

1 1

Total Ameren Missouri 21 $

9 $

30 1

4 $

8 $

13 Ameren Illinois Derivative liabilities commodity contracts:

Naturalgas 2 $

I $

3 3 $

12 $

3 $

18 Power

213 213

224 224 Total Ameren Illinois 2 $

214 $

216 3 $

12 $

227 $

242 Ameren Derivative liabilities commodity contracts(b) 21 $

2 $

223 $

246 4 $

16 $

235 $

255 Nuclear decommissioning trust fund:

Equity securities:

U.S. large capitalization Debt securities:

U.S. Treasury and agency securities Corporate bonds Other (a)

Balance excludes $6 million and $5 million of cash and cash equivalents, receivables, payables, and accrued income, net, for September 30, 2020, and December 31, 201 9, respectively.

(b)

See the Ameren Missouri and Ameren Illinois sections of the table for a breakout of the fair value of Amerens derivative assets and liabilities by type of commodity.

(c)

See the Ameren Missouri section of the table for a breakout of the fair value of Amerens nuclear decommissioning trust fund by investment type.

26

Level 3 fuel oils, natural gas, and uranium derivative contract assets and liabilities measured at fair value on a recurring basis were immaterial for all periods presented. The following table presents the fair value reconciliation of Level 3 power derivative contract assets and liabilities measured at fair value on a recurring basis for the three and nine months ended September 30, 2020 and 2019:

2020 2019 Ameren Ameren Ameren Ameren Missouri Illinois Ameren Missouri Illinois Ameren For the three months ended September 30:

Beginning balance at July 1 16 (229) $

(213) 15 (191) $

(176)

Realized and unrealized gains/(losses) included in regulatory assets/liabilities (2) 12 10 (4)

(17)

(21)

Settlements (4) 4

(1) 4 3

Transfers out of Level 3

(2)

(2)

Ending balance at September 30 10 $

(213) $

(203) 8 (204) $

(196)

Change in unrealized gain&(losses) related to assets/liabilities held at September 30 (2) $

I I 9

(4) $

(1 7) $

(21)

For the nine months ended September 30:

Beginning balance at January 1 I 3 (224) $

(21 1)

(1 83) $

(183)

Realized and unrealized gains/(losses) included in regulatory assets/liabilities 18 (2) 16 12 (32)

(20)

Settlements (21) 13 (8)

(2) 1 1 9

Transfers out of Level 3

(2)

(2)

Ending balance at September 30 10 (213)

(203) 8 (204)

(196)

Change in unrealized gains/(losses) related to assets/liabilities held at September 30 6

(1 ) $

5 8

(31 ) $

(23)

All gains or losses related to our Level 3 derivative commodity contracts are expected to be recovered or returned through customer rates; therefore, there is no impact to either net income or other comprehensive income resulting from changes in the fair value of these instruments.

The following table describes the valuation techniques and significant unobservable inputs utilized for the fair value of our Level 3 power derivative contract assets and liabilities as of September 30, 2020, and December 31

, 2019:

Fair Value Weighted Commodity Assets Liabilities Valuation Technique(s)

Unobservable Inputca)

Range Average(b) 2020 Power(c) 12 (215)

Discounted cash flow Average forward peak and off-peak 20 36 28 pricing forwards/swaps ($/MWh)

Nodal basis ($/MWh)

(5) I (2)

Trend rate (%)

3 4 3

2019 Power(d)

J4 (225)

Discounted cash flow Average forward peak and off-peak 22 34 25 pricing forwards/swaps ($/MWh)

Nodal basis ($/MWh)

(6) 0 (2)

Trendrate(%)

(1)0 0

(a)

Generally, significant increases (decreases) in these inputs in isolation would result in a significantly higher (lower) fair value measurement.

(b)

Unobservable inputs were weighted by relative fair value.

(c)

Valuations through 2029 use visible forward prices adjusted for nodal-to-hub basis differentials. Valuations beyond 2029 use a trend rate factor and are similarly adjusted for nodal-to-hub basis differentials.

(d)

Valuations through 2028 use visible forward prices adjusted for nodal-to-hub basis differentials. Valuations beyond 2028 use a trend rate factor and are similarly adjusted for nodal-to-hub basis differentials.

27

The following table sets forth the carrying amount and, by level within the fair value hierarchy, the fair value of financial assets and liabilities disclosed, but not recorded, at fair value as of September 30, 2020, and December 31

, 2019:

Carrying Fair Value Amount Level I Level 2 Level 3 Total September 30, 2020 Ameren:

Cash, cash equivalents, and restricted cash 168 168

168 Investments in industrial development revenue bondsfa) 263

263

263 Short-term debt 272

272

272 Long-term debt (including current portion)(a) 10,529 fb) 11,891 521 fc) 12,412 Ameren Missouri:

Cash, cash equivalents, and restricted cash 10 10

10 Advances to money pool 5

5

5 Investments in industrial development revenue bondsfa) 263

263

263 Long-term debt (including current portion)(a) 4,568 (b) 5,316

5,316 Ameren Illinois:

Cash, cash equivalents, and restricted cash 147 147

147 Short-term debt 242

242

242 Long-term debt (including current portion) 3,576 (b) 4,43J 4,431 December 31, 2019 Ameren:

Cash, cash equivalents, and restricted cash 176 176

176 Investments in industrial development revenue bonds(a) 263

263

263 Short-term debt 440

440

440 Long-term debt (including current portion)(a) 9,357 (b) 9,957 484 (c) 10,441 Ameren Missouri:

Cash, cash equivalents, and restricted cash 39 39

39 Investments in industrial development revenue bonds(a) 263

c 263

263 Short-term debt 234

234

234 Long-term debt (including current portion)(a) 4,190 (b) 4,772

4,772 Ameren Illinois:

Cash, cash equivalents, and restricted cash 125 125

125 Short-term debt 53

53

53 Long-term debt (including current portion) 3,575 (b) 4,019

4,019 (a)

Ameren and Ameren Missouri have investments in industrial development revenue bonds, classified as held-to-maturity and recorded in Other Assets, that are equal to the finance obligations for the Peno Creek and Audrain CT energy centers. As of September 30, 2020, and December 31

, 201 9, the carrying amount of both the investments in industrial development revenue bonds and the finance obligations approximated fair value.

(b)

Included unamortized debt issuance costs, which were excluded from the fair value measurement, of $77 million, $32 million, and $33 million for Ameren, Ameren Missouri, and Ameren Illinois, respectively, as of September 30, 2020. Included unamortized debt issuance costs, which were excluded from the fair value measurement, of$72 million, $30 million, and $34 million forAmeren, Ameren Missouri, and Ameren Illinois, respectively, as of December 31, 2019.

(c)

The Level 3 fair value amount consists of ATXIs senior unsecured notes.

NOTE 8 - RELATED-PARTY TRANSACTIONS In the normal course of business, Ameren Missouri and Ameren Illinois have engaged in, and may in the future engage in, affiliate transactions.

These transactions primarily consist of natural gas and power purchases and sales, services received or rendered, and borrowings and endings.

Transactions between Amerens subsidiaries are reported as affiliate transactions on their individual financial statements, but those transactions are eliminated in consolidation for Amerens consolidated financial statements, except as noted below. For a discussion of material related-party agreements and money pool arrangements, see Note 13 Related-party Transactions and Note 4 Short-term Debt and Liquidity under Part II, Item 8, of the Form 1 0-K.

Electric Power and Capacity Supply Agreements In April and September 2020, Ameren Illinois conducted procurement events, administered by the PA, to purchase energy products and acquire capacity. Ameren Missouri was among the winning suppliers in these events. As a result, in April 2020, Ameren Missouri contracted to supply a portion ofAmeren Illinois capacity requirements for $2 million from June 2021 through May 2023. In September 2020, Ameren Missouri contracted to supply a portion of Ameren Illinois capacity requirements for $1 million from June 2021 through May 2023. Additionally, in September 2020, Ameren Missouri and Ameren Illinois entered into an energy product agreement by which Ameren Missouri 28

agreed to seW, and Ameren Illinois agreed to purchase, 204,800 megawatthours at an average price of $31 per megawatthour during the period of September 2021 through November 2022.

Tax Allocation Agreement See Note 1 Summary ofSignificantAccounting Policies under Part II, Item 8, ofthe Form 10-Kfor a discussion ofthe tax allocation agreement. The following table presents the affiliate balances related to income taxes for Ameren Missouri and Ameren Illinois as of September 30, 2020, and December 31

, 2019:

September 30, 2020 December 31, 2019 Ameren Missouri Ameren Illinois Ameren Missouri Ameren Illinois Income taxes payable to parentfa) 38 $

9 15 43 Income taxes receivable from parent(b) 6 15 17 (a)

Included in Accounts payable affiliates on the balance sheet.

(b)

Included in Accounts receivable affiliates on the balance sheet.

Effects of Related-party Transactions on the Statement of Income The following table presents the effect on Ameren Missouri and Ameren Illinois of related-party transactions for the three and nine months ended September 30, 2020 and 2019:

Three Months Nine Months Income Statement Ameren Ameren Ameren Ameren Agreement Line Item Missouri Illinois Missouri Illinois Ameren Missouri powersupply Operating Revenues 2020 5

(a) $

11 (a) agreements with Ameren Illinois 201 9 1

(a) 3 (a)

Ameren Missouri and Ameren Illinois Operating Revenues 2020 6

(b) $

19 I

rent and facility services 2019 7

1 20 2

Ameren Missouri and Ameren Illinois Operating Revenues 2020 (b) $

I I

I miscellaneous support services 2019 1

(b) 1 1

Ameren Missouri software licensing Operating Revenues 2020 (a) $

(a) $

(a) $

(a) with Ameren IIIinois 2019 (a) 19 (a) 19 Total Operating Revenues 2020 II I

31 2

2019 9

20 24 22 Ameren Illinois power supply Purchased Power 2020 (a) $

5 (a) $

II agreements with Ameren Missouri 201 9 (a)

I (a) 3 Ameren Illinois transmission Purchased Power 2020 (a) $

(b) $

(a) $

I services with AIXI 201 9 (a)

I (a) 1 Total Purchased Power 2020 (a) $

5 (a) $

12 2019 (a) 2 (a) 4 Ameren Missouri and Ameren Illinois Other Operations and Maintenance 2020 (b) $

I (b) $

3 rent and facility services 2019 (b) 1 1

4 Ameren Services support services Other Operations and Maintenance 2020 36 34 I 03 98 agreement 2019 34 30 98 91 Total Other Operations and 2020 36 35 103 101 Maintenance 2019 34 31 99 95 Money pool borrowings (advances)

(Interest Charges)/Other Income, Net 2020 (b) $

(b) $

(b) $

(b) 2019 (b)

(b)

(b)

(b)

(a)

Not applicable.

(b)

Amount less than $1 million.

(c)

In September 201 9, Ameren Missouri purchased a license for advanced metering infrastructure software from Ameren Illinois. The amount of the $24 million cost-based transaction price over the $5 million remaining carrying value of the software was recorded as revenue by Ameren Illinois, with $14 million of revenue recorded at Ameren Illinois Electric Distribution and $5 million recorded at Ameren Illinois Natural Gas. The revenue recorded at Ameren Illinois Electric Distribution was reflected in formula ratemaking, which resulted in no impact to net income. Per authoritative accounting guidance for sales to rate-regulated entities, the revenue recognized by Ameren Illinois was not eliminated upon consolidation by Ameren.

NOTE 9 - COMMITMENTS AND CONTINGENCIES We are involved in legal, tax, and regulatory proceedings before various courts, regulatory commissions, authorities, and governmental agencies with respect to matters that arise in the ordinary course of business, some of which involve substantial amounts of money. We 29

believe that the final disposition of these proceedings, except as otherwise disclosed in the notes to our financial statements in this report and in the Form 10-K, will not have a material adverse effect on our results of operations, financial position, or liquidity.

Reference is made to Note 1 Summary of Significant Accounting Policies, Note 2 Rate and Regulatory Matters, Note 10 Callaway Energy Center, Note 13 Related-party Transactions, and Note 14 Commitments and Contingencies under Part II, Item 8, ofthe Form 10-K. See also Note 1 Summary of Significant Accounting Policies, Note 2 Rate and Regulatory Matters, Note 8 Related-party Transactions, and Note 10

Callaway Energy Center of this report.

Other Obligations To supply a portion of the fuel requirements of Ameren Missouris energy centers, Ameren Missouri has entered into various long-term commitments for the procurement of coal, natural gas, nuclear fuel, and methane gas. Ameren Missouri and Ameren Illinois also have entered into various long-term commitments for purchased power and natural gas for distribution. The table below presents our estimated minimum fuel, purchased power, and other commitments at September 30, 2020. Amerens and Ameren Illinois purchased power commitments include the Ameren Illinois agreements entered into as part of the PA-administered power procurement process. Included in the Other column are minimum purchase commitments under contracts for equipment, design and construction, and meter reading services, among other agreements, at September 30, 2020.

Natural Nuclear Purchased Methane Coal Gasta)

Fuel Power)(c)

Gas Other Total Ameren:

2020 94 52 3

57 (U) 39 245 2021 242 161 57 156 (U) 3 53 672 2022 193 108 12 63 3

23 402 2023 113 69 45 21 3

23 274 2024 94 28 20 4

3 20 169 Thereafter 55 73 21

21 61 231 Total 791 491 158 301 33 219 1,993 Ameren Missouri:

2020 94 12 3

22 131 2021 242 43 57

3 46 391 2022 193 38 12

3 23 269 2023 113 32 45

3 23 216 2024 94 13 20

3 20 150 Thereafter 55 22 21

21 24 143 Total 791 160 158

33 158 1,300 Ameren Illinois:

2020

40

57 (U) 14 111 2021

118

156 (U) 2 276 2022

70

63

133 2023

37

21

58 2024

15

4

19 Thereafter

51

51 Total

331

301

16 648 (a)

Includes amounts for generation and for distribution.

(b)

The purchased power amounts for Ameren and Ameren Illinois exclude agreements for renewable energy credits through 2035 with various renewable energy suppliers due to the contingent nature of the payment amounts, with the exception of expected payments of $36 million through 2024.

(c)

The purchased power amounts for Ameren and Ameren Missouri exclude a I 02-megawatt power purchase agreement with a wind farm operator, which expires in 2024, due to the contingent nature of the payment amounts.

(d)

In January 2018, as required by the FEJA, Ameren Illinois entered into agreements to acquire zero emission credits through 2026. Annual zero emission credit commitment amounts will be published by the IPA each May prior to the start of the subsequent planning year, which begins each June. The amounts above reflect Ameren Illinois commitment to acquire $42 million of zero emission credits through May 2021.

Environmental Matters We are subject to various environmental laws, including statutes and regulations, enforced by federal, state, and local authorities. The development and operation of electric generation, transmission, and distribution facilities and natural gas storage, transmission, and distribution facilities can trigger compliance obligations with respect to environmental laws. These laws address emissions; discharges to surface and groundwater; water consumption; impacts to air, land, and water; and chemical and waste storage, handling and disposal. Complex and lengthy processes are required to obtain and renew approvals, permits, and licenses for new, existing or modified facilities.

30

Additionally, the use and handling of various chemicals or hazardous materials require release prevention plans and emergency response procedures.

Environmental regulations have a significant impact on the electric utility industry and our operations. Compliance with these regulations could be costly for Ameren Missouri, which operates coal-fired power plants. Regulations that apply to air emissions from the electric utility industry include the NSPS, the CSAPR, the MATS, and the National Ambient Air Quality Standards, which are subject to periodic review for certain pollutants.

Collectively, these regulations cover a variety of pollutants, such as 502, particulate matter, NOR, mercury, toxic metals, and acid gases, and C02 emissions from new power plants. Water intake and discharges from power plants are regulated under the Clean Water Act. Such regulations require evaluation of the environmental impacts of water intake structures and could require modifications to water intake structures or more stringent limitations on wastewater discharges at Ameren Missouris energy centers, either of which could result in significant capital expenditures.

The management and disposal of coal ash is regulated as a solid waste under the Resource Conservation Recovery Act and a regulation known as the CCR rule, which will require the closure of our surface impoundments following the installations of dry ash handling systems at several of Ameren Missouris energy centers. The individual or combined effects of existing and new environmental regulations could result in significant capital expenditures, increased operating costs, or the closure or alteration of operations at some ofAmeren Missouris energy centers. Ameren and Ameren Missouri expect that such compliance costs would be recoverable through rates, subject to MoPSC prudence review, but the timing of costs and their recovery could be subject to regulatory lag.

Ameren and Ameren Missouri estimate that they will need to make capital expenditures of $200 million to $250 million from 2020 through 2024 in order to comply with existing environmental regulations. Additional environmental controls beyond 2024 could be required. This estimate of capital expenditures includes ash pond closure and corrective action costs required by the CCR regulations applicable to potential modifications to cooling water intake structures at existing power plants under Clean Water Act rules, and by effluent limitation guidelines applicable to steam electric generating units, all of which are discussed below. This estimate does not include capital expenditures that may be required as a result of the NSR and Clean Air Act litigation discussed below. Ameren Missouris current plan for compliance with existing air emission regulations includes burning low-sulfur coal and installing new or optimizing existing air pollution control equipment. The actual amount of capital expenditures required to comply with existing environmental regulations may vary substantially from the above estimate because of uncertainty as to future permitting requirements made by state regulators and the EPA, potential revisions to regulatory obligations, and the cost of potential compliance strategies, among other things.

The following sections describe the more significant environmental laws and rules and environmental enforcement and remediation matters that affect or could affect our operations. The EPA has initiated an administrative review of several regulations and proposed amendments to regulations and guidelines, including to the effluent limitation guidelines and the CCR Rule, which could ultimately result in the revision of all or part of such rules.

Clean Air Act Federal and state laws, including CSAPR, regulate emissions of 502 and NO through the reduction of emissions at their source and the use and retirement of emission allowances. CSAPR is implemented through a series of phases, and the second phase became effective in 2017.

Additional emission reduction requirements may apply in subsequent years. To achieve compliance with the CSAPR, Ameren Missouri burns low-sulfur coal, operates two scrubbers at its Sioux Energy Center, and optimizes other existing air pollution control equipment. Ameren Missouri expects to incur additional costs to lower its emissions at one or more of its energy centers to comply with the CSAPR in future years. These higher costs are expected to be recovered from customers through the FAC or higher base rates.

C02 Emissions Standards The EPAs Affordable Clean Energy Rule establishes emission guidelines for states to follow in developing plans to limit C02 emissions from coal-fired electric generating units. The EPA has identified certain efficiency measures as the best system of emission reduction for coal-fired electric generating units. The rule requires the state of Missouri to develop a compliance plan and submit it to the EPA for approval by July 2022.

The plan is expected to include a standard of performance for each affected generating unit. We continue to evaluate the impact of the adoption and implementation of the Affordable Clean Energy Rule. Ameren Missouri and other stakeholders are working with the state of Missouri to develop the compliance plan submitted to the EPA. At this time, Ameren Missouri cannot predict the outcome of Missouris compliance plan development process. As such, the impact on the results of operations, financial position, and liquidity of Ameren and Ameren Missouri is uncertain. We also cannot predict the outcome of any potential legal challenges to the rule.

NSR and Clean Air Litigation In January 201 1

, the Department of Justice, on behalf of the EPA, filed a complaint against Ameren Missouri in the United States District Court for the Eastern District of Missouri alleging that in performing projects at its coal-fired Rush Island Energy Center in 2007 and 2010, Ameren Missouri violated provisions of the Clean Air Act and Missouri law. In January 201 7, the district court issued a liability ruling and, in September 2019, entered a final order that required Ameren Missouri to install a flue gas desulfurization system at the Rush Island Energy Center and a dry sorbent injection system atthe Labadie Energy Center. There were no fines in the order. In October 2019, Ameren Missouri 31

appealed the district courts ruling to the United States Court of Appeals for the Eighth Circuit. The district court has stayed implementation of the majority of the requirements of its order while the case is under appeal. Ameren Missouri believes the district court both misinterpreted and misapplied the law in its ruling. Ameren Missouri is unable to predict the ultimate resolution of this mailer. Briefing in this case has been completed, but the appellate court has not yet scheduled oral arguments. The appellate court is under no deadline to issue a ruling in this case.

The ultimate resolution of this matter could have a material adverse effect on the results of operations, financial position, and liquidity of Ameren and Ameren Missouri. Among other things and subject to economic and regulatory considerations, resolution of this matter could result in increased capital expenditures for the installation of air pollution control equipment, as well as increased operations and maintenance expenses. Based upon engineering studies, capital expenditures to comply with the district courts order for installation of a flue gas desulfurization system at the Rush Island Energy Center are estimated at approximately $1 billion. Further, the flue gas desulfurization system would result in additional operation and maintenance expenses of $30 million to $50 million annually for the life of the energy center. Engineering studies required to develop estimated capital expenditures and estimated additional operation and maintenance expenses for the Labadie Energy Center to comply with the district courts order will not be undertaken while the case is under appeal. As a result of the district courts stay, Ameren Missouri does not expect to make significant capital expenditures or incur operations and maintenance expenses related to the district courts order while the case is under appeal.

Clean Water Act The EPAs Section 316(b) Rule requires power plant operators to evaluate cooling water intake structures and identify measures for reducing the number of aquatic organisms impinged on a power plants cooling water intake screens or entrained through the plants cooling water system. All of Ameren Missouris coal-fired and nuclear energy centers are subject to the cooling water intake structures rule. Requirements of the rule are being implemented through the permit renewal process of each energy centers water discharge permit, which is expected to be completed by 2023.

In 201 5, the EPA issued a rule to revise the effluent limitation guidelines applicable to steam electric generating units. These guidelines established national standards for water discharges that are based on the effectiveness of available control technology and prohibits effluent discharges of certain waste streams and imposes more stringent limitations on certain water discharges from power plants. To meet the requirements of the guidelines, Ameren Missouri has completed or will complete construction in 2020 of wastewater treatment facilities and dry ash handling systems at three of its four coal-fired energy centers. The fourth coal-fired energy center is scheduled to close permanently in 2022.

Estimated capital expenditures to complete these projects are included in the CCR management compliance plan, discussed below.

CCR Management In 201 5, the EPA issued the CCR rule, which established requirements for the management and disposal of CCR from coal-fired power plants.

These regulations affect CCR disposal and handling costs at Ameren Missouris energy centers. Ameren Missouri is in the process of closing surface impoundments at three facilities, and is scheduled to complete the last of such closures at all of its energy centers in 2023. While the EPA has issued a series of revisions to the CCR rule, none of those revisions or proposals is expected to materially impact our closure schedule. Ameren and Ameren Missouri have AROs of $125 million recorded on their respective balance sheets as of September 30, 2020, associated with CCR storage facilities. Ameren Missouri estimates it will need to make capital expenditures of $75 million to $125 million from 2020 through 2024 to implement its CCR management compliance plan, which includes installation of dry ash handling systems, wastewater treatment facilities, and groundwater monitoring equipment.

Remediation The Ameren Companies are involved in a number of remediation actions to clean up sites impacted by the use or disposal of materials containing hazardous substances. Federal and state laws can require responsible parties to fund remediation regardless of their degree of fault, the legality of original disposal, or the ownership of a disposal site.

As of September 30, 2020, Ameren Illinois has remediated the majority of the 44 former MGP sites in Illinois it owned or for which it was otherwise responsible. Ameren Illinois estimates it could substantially conclude remediation efforts at the remaining sites by 2023. The ICC allows Ameren Illinois to recover such remediation and related litigation costs from its electric and natural gas utility customers through environmental cost riders. Costs are subject to annual prudence review by the ICC. As of September 30, 2020, Ameren Illinois estimated the remaining obligation related to these former MGP sites at $106 million to $178 million. Ameren and Ameren Illinois recorded a liability of $106 million to represent the estimated minimum obligation for these sites, as no other amount within the range was a better estimate.

The scope of the remediation activities at these former MGP sites may increase as remediation efforts continue. Considerable uncertainty remains in these estimates because many site-specific factors can influence the ultimate actual costs, including unanticipated underground structures, the degree to which groundwater is encountered, regulatory changes, local ordinances, and site accessibility. The actual costs and timing of completion may vary substantially from these estimates.

32

Our operations or those of our predecessor companies involve the use of, disposal of, and, in appropriate circumstances, the cleanup of substances regulated under environmental laws. We are unable to determine whether such historical practices will result in future environmental commitments or will affect our results of operations, financial position, or liquidity.

NOTE JO - CALLAWAY ENERGY CENTER See Note 9 Callaway Energy Center under Part II, Item 8, ofthe Form 10-K for information regarding spent nuclear fuel recovery, recovery of decommissioning costs, and the nuclear decommissioning trust fund. The fair value of the trust fund for Ameren Missouris Callaway Energy Center is reported as Nuclear decommissioning trust fund in Amerens and Ameren Missouris balance sheets. This amount is legally restricted and may be used only to fund the costs of nuclear decommissioning. Changes in the fair value of the trust fund are recorded as an increase or decrease to the nuclear decommissioning trust fund, with an offsetting adjustment to the related regulatory liability. Ameren and Ameren Missouri have recorded an ARO for the Callaway Energy Center decommissioning costs at fair value, which represents the present value of estimated future cash outflows.

Annual decommissioning costs of $7 million are included in the costs used to establish electric rates for Ameren Missouris customers. Every three years, the MoPSC requires Ameren Missouri to file an updated cost study and funding analysis for decommissioning its Callaway Energy Center. An updated cost study and funding analysis was filed with the MoPSC in November 2020 and reflected within the ARO. See Note 1 3

- Supplemental Information for more information on Ameren Missouris ARCs.

Insurance The following table presents insurance coverage at Ameren Missouris Callaway Energy Center at September 30, 2020:

Most Recent Maximum Assessments Type and Source of Coverage Renewal Date Maximum Coverages for Single Incidents Public liability and nuclear worker liability:

American Nuclear Insurers January 1

, 2020 450

Pool participation (a) 13,348 (a) 138 (b) 13,798 fc) 138 Property damage:

NEIL and EMANI April 1

, 2020 3,200

25 (e)

Replacement power NEIL April 1, 2020 490 (f) 7 fe)

(a)

Provided through mandatory participation in an industrywide retrospective premium assessment program. The maximum coverage available is dependent on the number of United States commercial reactors participating in the program.

(b)

Retrospective premium under the Price-Anderson Act. This is subject to retrospective assessment with respect to a covered loss in excess of $450 million in the event of an incident at any licensed United States commercial reactor, payable at $21 million per year.

(c)

Limit of liability for each incident under the Price-Anderson liability provisions of the Atomic Energy Act of I 954, as amended. This limit is subject to change to account for the effects of inflation and changes in the number of licensed power reactors.

(d)

NEIL provides $2.7 billion in property damage, stabilization, decontamination, and premature decommissioning insurance for radiation events and $2.3 billion in property damage insurance for nonradiation events. EMANI provides $490 million in property damage insurance for both radiation and nonradiation events.

(e)

All NEIL-insured plants could be subject to assessments should losses exceed the accumulated funds from NEIL.

(f)

Provides replacement power cost insurance in the event of a prolonged accidental outage. Weekly indemnity up to $4.5 million for 52 weeks, which commences after the first 12 weeks of an outage, plus up to $3.6 million per week for a minimum of 71 weeks thereafter for a total not exceeding the policy limit of $490 million. Nonradiation events are limited to $328 million.

The Price-Anderson Act is a federal law that limits the liability for claims from an incident involving any licensed United States commercial nuclear energy center. The limit is based on the number of licensed reactors. The limit of liability and the maximum potential annual payments are adjusted at least every five years for inflation to reflect changes in the Consumer Price Index. The most recent five-year inflationary adjustment became effective in November 2018. Owners of a nuclear reactor cover this exposure through a combination of private insurance and mandatory participation in a financial protection pool, as established by the Price-Anderson Act.

Losses resulting from terrorist attacks on nuclear facilities insured by NEIL are subject to industrywide aggregates, such that terrorist acts against one or more commercial nuclear power plants within a stated time period would be treated as a single event, and the owners of the nuclear power plants would share the limit of liability. NEIL policies have an aggregate limit of $3.2 billion within a 12-month period for radiation events, or

$1.8 billion for events not involving radiation contamination, resulting from terrorist attacks. The EMANI policies are not subject to industrywide aggregates in the event of terrorist attacks on nuclear facilities.

If losses from a nuclear incident at the Callaway Energy Center exceed the limits of, or are not covered by insurance, or if coverage is unavailable, Ameren Missouri is at risk for any uninsured losses. If a serious nuclear incident were to occur, it could have a material adverse effect on Amerens and Ameren Missouris results of operations, financial position, or liquidity.

33

NOTE If RETIREMENT BENEFITS The following table presents the components of the net periodic benefit cost (income) incurred for Amerens pension and postretirement benefit plans for the three and nine months ended September 30, 2020 and 2019:

Pension Benefits Postretirement Benefits Three Months Nine Months Three Months Nine Months 2020 2019 2020 2019 2020 2019 2020 2019 Service cost(a) 28 22 83 66 4

4 14 13 Non-service cost components:

Interestcost 43 46 130 139 10 11 29 32 Expected return on plan assets (73)

(69)

(218)

(207)

(20)

(19)

(60)

(57)

Amortization of:

Prior service benefit

(1 )

(1 )

(1)

(3)

(4)

Actuarial loss (gain) 15 6

45 19 (3)

(4)

(7)

(11)

Total non-service cost components(b)

(15)

(17)

(44)

(49)

(14)

(13)

(41)

(40)

Net periodic benefit cost (income) 13 5

39 17 (10)

(9)

(27)

(27)

(a)

Service cost, net of capitalization, is reflected in Operating Expenses Other operations and maintenance on Amerens statement of income.

(b)

Non-service cost components are reflected in Other Income, Net on Amerens statement of income. See Note 5 Other Income, Net for additional information.

Ameren Missouri and Ameren Illinois are responsible for their respective share of Amerens pension and other postretirement costs. The following table presents the respective share of net periodic pension and other postretirement benefit costs (income) incurred for the three and nine months ended September 30, 2020 and 2019:

Pension Benefits Postretirement Benefits Three Months Nine Months Three Months Nine Months 2020 2019 2020 2019 2020 2019 2020 2019 Ameren Missourifa) 5 I

16 3

(2)

(1)

(4)

(4)

Ameren Illinois 8

5 24 15 (8)

(8)

(24)

(23)

Other

(1)

(1)

(1)

I

Amerenfa) 13 5

39 17 (10)

(9)

(27)

(27)

(a)

Does not include the impact of the regulatory tracking mechanism for the difference between the level of pension and postretirement benefit costs incurred by Ameren Missouri under GAAP and the level of such costs included in rates.

Funding Based on its assumptions at September 30, 2020, its investment performance in 2020, and its pension funding policy, the estimated aggregate contributions through 2024 has not materially changed from the $70 million expected aggregate contributions at December 31

, 2019.

NOTE 12 INCOME TAXES The following table presents a reconciliation of the federal statutory corporate income tax rate to the effective income tax rate for the three and nine months ended September 30, 2020 and 2019:

Ameren Ameren Missouri Ameren Illinois 2020 2019 2020 2019 2020 2019 Three Months Federalstatutorycorporateincometaxrate:

21%

21%

21%

21%

21%

21%

Increases (decreases) from:

Amortization of deferred investmenttax credit (1)

(1)

(1)

(1)

Amortization of excess deferred taxes (9)

(a)

(7)

(1 6)

(a)

(1 1)

(3)

(3)

Depreciation differences

(1)

Renewable and other tax credits (1 )

(2)

Statetax 4

6 4

5 7

6 Stock-based compensation I

1

Effective income tax rate 15%

20%

6%

14%

24%

24%

34

Ameren Ameren Missouri Ameren Illinois 2020 2019 2020 2019 2020 2019 Nine Months Federaistatutorycorporateincometaxcate:

21%

21%

21%

21%

21%

21%

Increases (decreases) from:

Amortization of deferred investmenttax credit

(1)

(1)

(1)

Amortization of excess deferred taxes (9)

(a)

(7)

(16)

(a)

(12)

(3)

(4)

Renewable and other tax credits (1)

(1)

Statetax 5

6 3

5 7

7 Stock-based compensation (1)

(1)

Effective income tax rate 15%

18%

6%

13%

25%

24%

(a)

Increase in the amortization of excess deferred taxes pursuant to the MoPSCs March 2020 electric rate order. See Note 2 Rate and Regulatory Matters for additional information.

NOTE 13 SUPPLEMENTAL INFORMATION Cash, Cash Equivalents, and Restricted Cash The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the balance sheets and the statements of cash flows as of September 30, 2020, and December 31

, 2019:

September 30, 2020 December 31, 2019 Ameren Ameren Ameren Ameren Ameren Missouri Illinois Ameren Missouri Illinois cash and cash equivalents 6

16 9

Restricted cash included in Other current assets 14 4

5 14 4

5 Restricted cash included in Other assets 142

142 120

120 Restricted cash included in Nuclear decommissioning trust fund 6

6

26 26

Total cash, cash equivalents, and restricted cash 168 10 147 176 39 125 Restricted cash included in Other current assets primarily represents funds held by an irrevocable Voluntary Employee Beneficiary Association (VEBA) trust, which provides health care benefits for active employees. Restricted cash included in Other assets on Amerens and Ameren Illinois balance sheets primarily represents amounts collected under a cost recovery rider restricted for use in the procurement of renewable energy credits and amounts in a trust fund restricted for the use of funding certain asbestos-related claims.

Accounts Receivable Accounts receivable trade on Amerens and Ameren Illinois balance sheets include certain receivables purchased at a discount from alternative retail electric suppliers that elect to participate in the utility consolidated billing program. At September 30, 2020, and December 31

, 2019, Other current liabilities on Amerens and Ameren Illinois balance sheets included payables for purchased receivables of $36 million and $32 million, respectively.

35

The following table provides a reconciliation of the beginning and ending amount of the allowance for doubtful accounts for the three and nine months ended September 30, 2020 and 2019:

Three Months Nine Months 2020 2019 2020 2019 Ameren:

Beginningolperiod 25 19 17 18 Baddebtexpense 21 14 31 22 Net write-offs (2)

(14)

(4)

(21)

End of period 44 I 9 44 I 9 Ameren Missouri:

Beginning of period 9

7 7

7 Bad debt expense 5

3 9

6 Net write-offs

(2)

(2)

(5)

Endofperiod 14 8

14 8

Ameren Illinois:(a)

Beginning ofPeriod 16 12 10 11 Baddebtexpense 16 11 22 16 Netwrite-offs (2)

(12)

(2)

(16)

EndofPeriod 30 11 30 11 (a)

Ameren Illinois has rate-adjustment mechanisms that allow it to recover the difference between its actual net bad debt write-offs under GAAP, including those associated with receivables purchased from alternative retail electric suppliers, and the amount of net bad debt write-offs included in its base rates. In 2020, the rate-adjustment mechanism for electric distribution allows for recovery of bad debt expense recognized under GAAP. See Note 2 Rate and Regulatory Matters for additional information.

Net write-offs decreased for the three and nine months ended September 30, 2020, compared with the year-ago periods, due to the temporary suspension of disconnecting customers for nonpayment. See Note 2 Rate and Regulatory Matters for additional information.

Supplemental Cash Flow Information The following table provides noncash financing and investing activity excluded from the statements of cash flows for the nine months ended September 30, 2020 and 2019:

September 30, 2020 September 30, 2019 Ameren Ameren Ameren Ameren Ameren Missouri Illinois Ameren Missouri Illinois Investing Exchange of bond investments for the extinguishment of senior unsecured notes

1 7 $

I 7 Accrued capital expenditures 311 115 191 273 138 128 Net realized and unrealized gain (loss) nuclear decommissioning trust fund 43 43

1 00 1 00

Financing Exchange of bond investments for the extinguishment of senior unsecured notes

(1 7) $

(17)

Issuance of common stock for stock-based compensation 38

54

Asset Retirement Obligations The following table provides a reconciliation of the beginning and ending carrying amount of AROs for the nine months ended September 30, 2020:

Ameren Ameren Missouri Illinois Ameren Balance at December31, 2019 687 4

(a) 691 (b)

Liabilities settled (42)

(42)

Accretion 21

)c)

)c) 22

)c)

Change in estimates 57 (U) 57

)d)

Balance at September 30, 2020 723 5

(a) 728

)b)

(a)

Included in Other deferred credits and liabilities on the balance sheet.

(b)

Balance included $53 million in Other current liabilities on the balance sheet as of both December 31, 201 9, and September 30, 2020.

(c)

Accretion expense attributable to Ameren Missouri and Ameren Illinois was recorded as a decrease to regulatory liabilities and an increase to regulatory assets, respectively.

36

(d)

Ameren Missouri changed its fair value estimate primarily due to an update to the decommissioning of the Callaway Energy Center to reflect the cost study and funding analysis filed with the MoPSC in November 2020 and an increase in the cost estimate for closure of certain CCR storage facilities.

Stock-based Compensation on January 1, 2020, Ameren granted 294,320 performance share units with a grant date fair value of $24 million and I 32,307 restricted share units with a grant date fair value of $1 0 million. Awards vest approximately 38 months after the grant date or on a pro-rata basis upon death or eligible retirement. The performance share units vest based on the achievement of certain specified market performance measures (252,370 performance share units) or based on the achievement of renewable generation and energy storage installation targets (41 950 performance share units). The exact number of shares issued pursuant to a performance share unit varies from 0% to 200% of the target award, depending on actual company performance relative to the performance goals.

On September 18, 2020, Ameren granted certain executive officers an additional 37,104 restricted share units with a grant date fair value of

$3 million, which will vest after three years on September 17, 2023. The awards do not provide for pro rata vesting in connection with the executive officers retirement.

For the nine months ended September 30, 2020 and 201 9, excess tax benefits associated with the settlement of stock-based compensation awards reduced income tax expense by $8 million and $14 million, respectively.

Deferred Compensation As of September 30, 2020, and December 31, 201 9, the present value of benefits to be paid for deferred compensation obligations was $88 million and $86 million, respectively, which was primarily reflected in Other deferred credits and liabilities on Amerens consolidated balance sheet.

Operating Revenues As of September 30, 2020 and 201 9, our remaining performance obligations for contracts with a term greater than one year were immaterial.

The Ameren Companies elected not to disclose the aggregate amount of the transaction price allocated to the performance obligations that are unsatisfied as of the end of the reporting period for contracts with an initial expected term of one year or less.

See Note 14 Segment Information for disaggregated revenue information.

Excise Taxes Ameren Missouri and Ameren Illinois collect from their customers excise taxes, including municipal and state excise taxes and gross receipts taxes that are levied on the sale or distribution of natural gas and electricity. The following table presents the excise taxes recorded on a gross basis in Operating Revenues Electric, Operating Revenues Natural gas and Operating Expenses Taxes other than income taxes on the statements of income for the three and nine months ended September 30, 2020 and 2019:

Three Months Nine Months 2020 2019 2020 2019 AmerenMissouri 45 49 111 118 Ameren Illinois 26 27 87 91 Ameren 71 76 198 209 Earnings per Share The following table reconciles the basic weighted-average number of common shares outstanding to the diluted weighted-average number of common shares outstanding for the three and nine months ended September 30, 2020 and 2019:

Three Months Nine Months 2020 2019 2020 2019 Weighted-average Common Shares Outstanding Basic 247.1 245.9 246.8 245.5 Assumed settlement of performance share units and restricted stock units I.5 1.4 1.2 1.4 Dilutive effect offorward sale agreement 0.6 0.2 0.4 0.1 Weighted-average Common Shares Outstanding Diluted(a) 249.2 247.5 248.4 247.0 (a)

There were no potentially dilutive securities excluded from the earnings per diluted share calculations for the three and nine months ended September 30, 2020 and 2019.

37

NOTE 14 SEGMENT INFORMATION The following tables present revenues, net income (loss) attributable to common shareholders, and capital expenditures by segment at Ameren and Ameren Illinois for the three and nine months ended September 30, 2020 and 201 9. Ameren, Ameren Missouri, and Ameren Illinois management review segment capital expenditure information rather than any individual or total asset amount. For additional information about our segments, see Note 16 Segment Information under Part II, Item 8, ofthe Form 10-K.

Ameren Ameren Ameren Illinois Illinois Ameren Electric Natural Ameren Intersegment Missouri Distribution Gas Transmission Other Eliminations Ameren Three Months 2020:

External revenues 990 390 122 126

1,628 Intersegment revenues If I

15 (a)

(27)

Net income (loss) attributable to Ameren common shareholders 297 34 2

62

)b)

(28)

367 Capital expenditures 262 129 81 185 2

(3) 656 Three Months 2019:

Externairevenues 1,050 374 107 109

1,640 Intersegment revenues 9

15 5

19 (a)

(29) 19

)c)

Net income (loss) attributable to Ameren common shareholders 300 32 (1) 53 (b)

(20)

364 Capital expenditures 256 1 39 1 1 3 1 29 (7) 6 636 Nine Months 2020:

External revenues 2,442 1,131 533 360

4,466 Intersegment revenues 31 2

40 (a)

(73)

Net income (loss) attributable to Ameren common shareholders 439 107 66 168

)b)

(24)

756 Capital expenditures 778 391 221 490 4

1,884 Nine Months 2019:

Externairevenues 2,591 S

1,118 563 303

4,575 Intersegment revenues 24 17 5

48 (a)

(75) 19

)c)

Net income (loss) attributable to Ameren common shareholders 446 105 57 139

)b(

(13)

734 Capital expenditures 751 390 241 377 3

(1) 1,761 (a)

Ameren Transmission earns revenue from transmission service provided to Ameren Illinois Electric Distribution.

(b)

Ameren Transmission earnings reflect an allocation of financing costs from Ameren (parent).

(c)

Intersegment revenues at Ameren include $14 million and $5 million of revenue from Ameren Illinois Electric Distribution and Ameren Illinois Natural Gas, respectively, for the three and nine months ended September 30, 201 9, for a software licensing agreement with Ameren Missouri. Under authoritative accounting guidance for rate-regulated entities, the revenue recognized by Ameren Illinois was not eliminated upon consolidation. See Note 8 Related-party Transactions under Part I, Item I, of this report for additional information.

Ameren Illinois Ameren Illinois Ameren Electric Illinois Ameren Illinois Intersegment Distribution Natural Gas Transmission Eliminations Ameren Illinois Three Months 2020:

External revenues 391 122 76

589 Intersegment revenues

15 (a)

(15)

Net income available to common shareholder 34 2

41

77 Capital expenditures 129 81 160

370 Three Months 2019:

Externalrevenues 389 112 63

564 Intersegment revenues

18 (a)

(18)

Net income (loss) available to common shareholder 32 (1) 34

65 Capital expenditures 139 113 92

344 38

Ameren Illinois Ameren Electric Illinois Ameren Illinois Intersegment Ameren Distribution Natural Gas Transmission Eliminations Illinois Nine Months 2020:

External revenues 1,133 533 213

1,879 Intersegment revenues

39 (a)

(39)

Net income available to common shareholder 107 66 107

280 Capital expenditures 391 221 419

1,031 Nine Months 2019:

Externalrevenues 1,135 568 170

1,873 Intersegment revenues

47 (a)

(47)

Net income available to common shareholder 105 57 85

247 Capital expenditures 390 241 269

900 (a)

Ameren Illinois Transmission earns revenue from transmission service provided to Ameren Illinois Electric Distribution.

The following tables present disaggregated revenues by segment at Ameren and Ameren Illinois for the three and nine months ended September 30, 2020 and 201 9. Economic factors affect the nature, timing, amount, and uncertainty of revenues and cash flows in a similar manner across customer classes. Revenues from alternative revenue programs have a similar distribution among customer classes as revenues from contracts with customers. Other revenues not associated with contracts with customers are presented in the Other customer classification, along with electric transmission and off-system revenues.

Ameren Ameren Illinois Ameren Electric Ameren Illinois Ameren Intersegment Missouri Distribution Natural Gas Transmission Eliminations Ameren Three Months 2020:

Residential 455 234

689 Commercial 343 127

470 Industrial 87 26

113 Other 99 4

141 (27) 217 Total electric revenues 984 391

141 (27) 1,489 Residential 8

68

76 Commercial 3

18

21 Industrial I

5

6 Other 5

31

36 Totalgasrevenues 17

122

139 Total revenues)a) 1,001 391 122 141 (27) 1,628 Three Months 2019:

Residential 489 224

713 Commercial 394 123

517 Industrial 94 27

121 Other 63 15

)b) 128 (29) 177 Totalelectricrevenues 1,040 389

128 (29) 1,528 Residential 8

65

73 Commercial 4

17

21 Industrial I

2

3 Other 6

28

)b) 34 Totalgasrevenues 19

112

131 Totalrevenues)a) 1,059 389 112 128 (29) 1,659 39

Ameren Illinois Ameren Electric Ameren Illinois Ameren Intersegment Missouri Distribution Natural Gas Transmission Eliminations Ameren Nine Months 2020:

Residential 1,111 664

1,775 Commercial 828 365

1,193 Industrial 207 91

298 Other 240 13

400 (73) 580 Total electric revenues 2,386 1,133

400 (73) 3,846 Residential 52

375

427 Commercial 20

94

ff4 Industrial 3

If

14 Other 12

53

65 Total natural gas revenues 87

533

620 Total revenuesfa) 2,473 1,133 533 400 (73) 4,466 Nine Months 2019:

Residential 1,134 640

1774 Commercial 943 370

1,313 Industrial 226 94

320 Other 214 31 fb) 351 (75) 521 Totalelectricrevenues 2,517 1,135

351 (75) 3,928 Residential 56

399

455 Commercial 24

105

129 Industrial 3

9

12 Other 15

55 (b) 70 Total natural gas revenues 98

568

666 Total revenuesfa) 2,615 1,135 568 351 (75) 4,594 (a)

The following table presents increases/(decreases) in revenues from alternative revenue programs and other revenues not from contracts with customers for the three and nine months ended September 30, 2020 and 2019:

Ameren Illinois Ameren Ameren Electric Illinois Ameren Missouri Distribution Natural Gas Transmission Ameren Three Months 2020:

Revenues from alternative revenue programs I

(110) 3 4

(102)

Other revenues not from contracts with customers 6

5

I I Three Months 2019:

Revenues from alternative revenue programs 26 (145) 1 (12)

(130)

Other revenues not from contracts with customers 5

1 1

7 Nine Months 2020:

Revenues from alternative revenue programs (8)

(59) 17 34 (16)

Other revenues not from contracts with customers 21 6

1

28 Nine Months 2019:

Revenues from alternative revenue programs 41 (1 1 1 )

2 (25)

(93)

Other revenues not from contracts with customers 14 5

2

21 (b)

Includes $14 million and $5 million forAmeren Illinois Electric Distribution and Ameren Illinois Natural Gas, respectively, forthe three and nine months ended September 30, 201 9, for a software licensing agreement with Ameren Missouri. See Note 8 Related-party Transactions for additional information.

40

Ameren Illinois

Ameren Illinois Ameren Electric Illinois Ameren Illinois Intersegment Ameren Distribution Natural Gas Transmission Eliminations Illinois Three Months 2020:

Residential 234 68

302 Commercial 127 18

145 Industrial 26 5

31 Other 4

31 91 (15) 111 Total revenues(a) 391 122 91 (15) 589 Three Months 2019:

Residential 224 65

289 Commercial 123 17

140 Industrial 27 2

29 Other 15 (b) 28 (b) 81 (18) 106 Totairevenuesfa) 389 112 81 (18) 564 Nine Months 2020:

Residential 664 375

1,039 Commercial 365 94

459 Industrial 91 11

102 Other 13 53 252 (39) 279 Total revenues(a) 1,133 533 252 (39) 1,879 Nine Months 2019:

Residential 640 399

1,039 Commercial 370 105

475 Industrial 94 9

103 Other 31 (b) 55 (b) 217 (47) 256 Totalrevenues(a) 1,135 568 217 (47) 1,873 (a)

The following table presents increases/(decreases) in revenues from alternative revenue programs and other revenues not from contracts with customers for the Ameren Illinois segments for the three and nine months ended September 30, 2020 and 2019:

Ameren Illinois Electric Ameren Illinois Ameren Illinois Distribution Natural Gas Transmission Ameren Illinois Three Months 2020:

Revenues from alternative revenue programs (110) 3 5

(102)

Other revenues not from contracts with customers 5

5 Three Months 2019:

Revenues from alternative revenue programs (145)

I (12)

(156)

Other revenues not from contracts with customers I

I

2 Nine Months 2020:

Revenues from alternative revenue programs (59) 17 29 (13)

Other revenues not from contracts with customers 6

1

7 Nine Months 2019:

Revenues from alternative revenue programs (1 1 1 )

2 (26)

(135)

Other revenues not from contracts with customers 5

2

7 (b)

Includes $14 million and $5 million forAmeren Illinois Electric Distribution and Ameren Illinois Natural Gas, respectively, forthe three and nine months ended September 30, 201 9, for a software licensing agreement with Ameren Missouri. See Note 8 Related-party Transactions for additional information.

ITEM 2. MANAGEMENTS DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

The following discussion should be read in conjunction with the financial statements and Risk Factors contained in this Form 1O-Q, as well as Managements Discussion and Analysis of Financial Condition and Results of Operations and Risk Factors contained in the Form 1 0-K. We intend for this discussion to provide the reader with information that will assist in understanding our financial statements, the changes in certain key items in those financial statements, and the primary factors that accounted for those changes, as well as how certain accounting principles affect our financial statements. The discussion also provides information about the financial results of our business segments to provide a better understanding of how those segments and their results affect the financial condition and results of operations of Ameren as a whole. Also see the Glossary of Terms and Abbreviations at the front of this report and in the Form 10-K.

41

Ameren, headquartered in St. Louis, Missouri, is a public utility holding company whose primary assets are its equity interests in its subsidiaries.

Amerens subsidiaries are separate, independent legal entities with separate businesses, assets, and liabilities. Dividends on Amerens common stock and the payment of expenses by Ameren depend on distributions made to it by its subsidiaries. Amerens principal subsidiaries are listed below. Ameren has other subsidiaries that conduct other activities, such as providing shared services.

Union Electric Company, doing business as Ameren Missouri, operates a rate-regulated electric generation, transmission, and distribution business and a rate-regulated natural gas distribution business in Missouri.

Ameren Illinois Company, doing business as Ameren Illinois, operates rate-regulated electric transmission, electric distribution, and natural gas distribution businesses in Illinois.

AIXI operates a FERC rate-regulated electric transmission business in the MISO.

Amerens financial statements are prepared on a consolidated basis and therefore include the accounts of its majority-owned subsidiaries. All intercompany transactions have been eliminated, except as disclosed in Note 8 Related-party Transactions. Ameren Missouri and Ameren Illinois have no subsidiaries. All tabular dollar amounts are in millions, unless otherwise indicated.

In addition to presenting results of operations and earnings amounts in total, we present certain information in cents per share. These amounts reflect factors that directly affect Amerens earnings. We believe this per share information helps readers to understand the impact of these factors on Amerens earnings per share.

OVERVIEW Net income attributable to Ameren common shareholders in the three months ended September 30, 2020, was $367 million, or $1.47 per diluted share, compared with $364 million, or $1.47 per diluted share, in the year-ago period. Net income attributable to Ameren common shareholders in the nine months ended September 30, 2020, was $756 million, or $3.04 per diluted share, compared with $734 million, or $2.97 per diluted share, in the year-ago period. Net income for the three and nine months ended September 30, 2020, compared to the year-ago periods, was favorably affected by the results of Ameren Missouris March 2020 electric rate order and infrastructure investments that drove higher earnings at Ameren Transmission and Ameren Illinois Electric Distribution. Earnings for the three and nine months ended September 30, 2020, compared to the year-ago periods, were also favorably affected by lower other operations and maintenance expenses not subject to riders or regulatory tracking mechanisms, primarily due to lower electric system infrastructure maintenance expenses as a result of decreased system load, disciplined cost management, and the deferral of projects to future periods. Net income for the three and nine months ended September 30, 2020, compared to the year-ago periods, was unfavorably affected by lower revenues due to reduced MEEIA performance incentives; decreased electric retail sales at Ameren Missouri due to milder summer temperatures in 2020 and due, in part, to the COVID-19 pandemic; a lower recognized ROE at Ameren Illinois Electric Distribution; and higher net financing costs, primarily at Ameren (parent). Net income for the nine months ended September 30, 2020, compared to the year-ago period, was favorably affected by the absence in 2020 of expenses related to the Callaway Energy Centers 2019 scheduled refueling and maintenance outage, increased Ameren Transmission earnings resulting from the May 2020 FERC order addressing the allowed base ROE, and increased Ameren Illinois Natural Gas earnings from investments. Earnings for the nine months ended September 30, 2020, compared to the year-ago period, were unfavorably affected by decreased income tax benefits at Ameren (parent) related to stock-based compensation.

Amerens strategic plan includes investing and operating its utilities in a manner consistent with existing regulatory frameworks, enhancing those frameworks, and advocating for responsible energy and economic policies, as well as creating and capitalizing on opportunities for investment for the benefit of its customers, shareholders, and the environment. Ameren remains focused on disciplined cost management and strategic capital allocation. Ameren believes it has constructive regulatory frameworks for investment at all of its utility businesses and invested $1.9 billion in those businesses in the nine months ended September 30, 2020.

The COVID-19 pandemic continues to be a rapidly evolving situation. In the first nine months of 2020, we experienced a net decrease in our sales volumes, an increase in our accounts receivable balances that were past due or that were a part of a deferred payment arrangement, and a decline in our cash collections from customers. The continued effect ofthe COVID-19 pandemic on our results of operations, financial position, and liquidity in subsequent periods will depend on its severity and longevity, future regulatory or legislative actions with respect thereto, and the resulting impact on business, economic, and capital market conditions. Shelter-in-place orders began taking effect in our service territories in mid-March 2020. These orders generally required individuals to remain at home and precluded or limited the operation of businesses that were deemed nonessential. In early 2020, Ameren began implementing its business continuity plans, and continues to take measures to mitigate the risk of COVID-19 transmission. Actions included restricting travel for employees, implementing work-from-home policies, securing and supplying personal protective equipment, and implementing work practices to ensure the safety of our employees and customers, while maintaining social distancing.

While our business operations were deemed essential and were not directly impacted by the shelter-in-place orders, approximately 65% of our workforce transitioned to remote working arrangements in mid-March 2020. In early June 2020, a small portion of our workforce began the process of returning to our work locations under a phased approach and approximately 50% of our workforce continues to work remotely. In mid-May 2020, shelter-in-place orders effective in our service territories began to be relaxed, with fewer restrictions on social activities and nonessential businesses beginning to reopen. However, 42

certain restrictions remain in place that limit individual activities and the operation of nonessential businesses. Additional restrictions may be imposed in the future. We continue to assess the impacts the pandemic is having on our businesses, including impacts on electric and natural gas sales volumes, liquidity, bad debt expense, and supply chain operations. For further discussion of these and other matters, see Note 2 Rate and Regulatory Matters under Part I, Item 1, of this report, and Results of Operations, Liquidity and Capital Resources, and Outlook sections below. In addition, for information regarding Ameren Missouris and Ameren Illinois suspension and subsequent reinstatement of customer disconnection activities and late fee charges for nonpayment, see Note 2 Rate and Regulatory Matters under Part I, Item 1

, of this report.

In February 2020, Ameren Missouri filed an update to its Smart Energy Plan with the MoPSC, which includes a five-year capital investment overview with a detailed one-year plan for 2020. The plan is designed to upgrade Ameren Missouris electric infrastructure and includes investments that will upgrade the grid and accommodate more renewable energy. Investments under the plan are expected to total approximately $7.6 billion over the five-year period from 2020 through 2024, with expenditures largely eligible for recovery under the PISA and the RESRAM. These investments exclude incremental renewable generation investment opportunities of 950 megawatts by 2024, which are included in Ameren Missouris 2020 IRP discussed below. The planned investments beyond 2023 included in the five-year range above are based on the assumption that Ameren Missouri requests and receives MoPSC approval of an extension of the PISA.

In February 2020, the MoPSC issued an order approving a stipulation and agreement allowing Ameren Missouri to defer and amortize maintenance expenses related to scheduled refueling and maintenance outages at its Callaway Energy Center. Maintenance expenses associated with the fall 2020 refueling and maintenance outage are being deferred, as incurred, as a regulatory asset, and will be amortized after completion of the outage. Maintenance expenses will be amortized overthe period between refueling and maintenance outages, which is approximately 18 months. Deferring and amortizing these expenses allows the timing of expense recognition to more closely align with revenues and mitigates future earnings volatility between outage and non-outage years.

In March 2020, the MoPSC issued an order in Ameren Missouris July 2019 electric service regulatory rate review, approving nonunanimous stipulation and agreements. The order resulted in a decrease of $32 million to Ameren Missouris annual revenue requirement for electric retail service, which reflects infrastructure investments as of December 31

, 201 9. The order also provided for the continued use of the FAC and trackers for pension and postretirement benefits, uncertain income tax positions, and certain excess deferred income taxes that the MoPSC previously authorized in earlier electric rate orders. In addition, the order required Ameren Missouri to donate $8 million to low-income assistance programs, which was reflected in results of operations in the first quarter of 2020. The new rates became effective on April 1

, 2020.

In August 2020, the MoPSC issued an order approving a unanimous stipulation and agreement with respect to the 2022 program year of Ameren Missouris six-year MEEIA 2019 program and related performance incentives. The order also approved Ameren Missouris energy savings results for the first year of the MEEIA 201 9 program. As a result of this order and in accordance with revenue recognition guidance, Ameren Missouri recognized revenues of $6 million in the third quarter of 2020.

In September 2020, Ameren Missouri filed its 2020 IRP with the MoPSC. In connection with the 2020 IRP filing, Ameren established a goal of achieving net-zero carbon emissions by 2050. Ameren is also targeting a 50% C02 emission reduction by 2030 and an 85% reduction by 2040 from the 2005 level. The plan targets cleaner and more diverse sources of energy generation, including solar, wind, hydro, and nuclear power, and supports increased investment in new energy technologies. The plan, which is subject to review by the MoPSC, also includes expanding renewable sources by adding 3, 1 00 megawatts of renewable generation by the end of 2030 and a total of 5,400 megawatts of renewable generation by 2040.

These amounts include the 700 megawatts of wind generation projects discussed below, which are expected to be substantially complete in 2020 and fully in-service in early 2021, and will support Ameren Missouris compliance with the state of Missouris requirement of achieving I 5% of native load sales from renewable energy sources by 2021

, subject to customer rate increase limitations. Based on current and projected market prices for energy and for wind and solar generation technologies, among other factors, Ameren Missouri expects its ownership of these renewable resources would represent the lowest-cost option for customers. The plan also includes advancing the retirement dates of the Sioux and Rush Island coal-fired energy centers to 2028 and 2039, respectively, which are subject to the approval of a change in the assets depreciable lives by the MoPSC in a future regulatory rate review, the continued implementation of customer energy-efficiency programs, and the expectation that Ameren Missouri will seek an extension of the operating license for the Callaway Energy Center beyond its current 2044 expiration date. Additionally, the plan includes retiring the Meramec and Labadie coal-fired energy centers at the end of their useful lives, or by 2022 and 2042, respectively.

In October 2020, Ameren Missouri filed requests with the MoPSC for accounting authority orders related to its electric and natural gas services.

The orders would allow Ameren Missouri to accumulate certain costs incurred related to the COVID-1 9 pandemic and forgone customer late fee revenues from March 2020 to June 2021

, for potential recovery in future electric and natural gas service regulatory rate reviews. These costs would be net of any cost savings Ameren Missouri realizes as a result of the COVID-1 9 pandemic. The orders would also allow Ameren Missouri to accumulate bad debt write-offs incurred from March 2020 to September 2021 due to the COVID-1 9 pandemic, for potential recovery in future electric and natural gas service regulatory rate reviews. The requests include an estimated $9 million of costs incurred, net of savings, and forgone customer late fee revenues related to the COVID-19 pandemic from March 2020 through September 43

2020. The requests did not seek accumulation for potential recovery of forgone revenues associated with decreased sales volumes related to the COVID-1 9 pandemic. The MoPSC is under no deadline to issue orders, and Ameren Missouri cannot predict the ultimate outcome of these regulatory proceedings.

Construction on the new wind generation facilities continues to progress. Delays to the original construction schedule have occurred in 2020 due to changes in supply and construction activities. During the third quarter of 2020, all remaining wind turbine deliveries for the up-to 400-megawatt project were completed. Based on the construction schedule, Ameren Missouri expects this project to be placed in-service by the end of 2020. At this time, due to manufacturing, shipping, and other supply chain issues in 2020, and, based on an updated construction schedule from the developer, Ameren Missouri expects the up-to 300-megawatt project to be partially placed in-service by the end of 2020, and the remaining portion of the project, representing approximately $200 million of investment, to be placed in-service in the first quarter of 2021

. Ameren Missouri and the developer of the up-to 300-megawatt project continue to monitor the impact to this projects schedule. In May 2020, the IRS issued guidance that extended the in-service date criteria to December 31, 2021

, for qualifying for federal production tax credits. As a result of this extension, Ameren does not anticipate that delays in the completion of the wind generation facilities will affect Amerens ability to realize anticipated federal production tax credits.

In February 2020, Ameren Illinois filed a request with the ICC seeking approval to increase its annual revenues for natural gas delivery service.

In September 2020, Ameren Illinois filed a revised request seeking to increase its annual revenues for natural gas delivery service by $97 million, which includes an estimated $46 million of annual revenues that would otherwise be recovered under the QIP and other riders. The request is based on a 10.5% ROE, a capital structure composed of 54.1% common equity, and a rate base of $2.1 billion. Ameren Illinois used a 2021 future test year in this proceeding. In October 2020, the ICC staff recommended an increase to annual revenues for natural gas delivery service of $69 million, based on a 9.3% ROE, a capital structure composed of 50.4% common equity, and a rate base of $2.1 billion. A decision by the ICC in this proceeding is required by January 2021

, with new rates expected to be effective in February 2021

. Ameren Illinois cannot predict the level of any delivery service rate change the ICC may approve, nor whether any rate change that may eventually be approved will be sufficient to enable Ameren Illinois to earn a reasonable return on investments when the rate changes go into effect.

In April 2020, Ameren Illinois filed its annual electric distribution service formula rate update with the ICC, requesting a reduction of $45 million in its rates. In September 2020, the ICC staff submitted its revised calculation of the revenue requirement included in Ameren Illinois update filing, recommending a $49 million decrease in Ameren Illinois electric distribution service rates. An ICC decision in this proceeding is expected by December 2020, with new rates effective January 2021.

In May 2020, in connection with customer complaint cases filed with the FERC relating to the allowed base ROE, the FERC issued an order addressing the requests for rehearing, which setthe allowed base ROE at 10.02%, superseding the 9.88% previously ordered, and required refunds, with interest, for the periods November 2013 to February 2015 and from late September 2016 forward. The May 2020 order also denied rehearing ofthe FERCs dismissal ofthe February 2015 complaint case. In July 2020, Ameren Missouri, Ameren Illinois, and ATXI filed an appeal of the May 2020 order to the United States Court of Appeals for the District of Columbia Circuit challenging the refunds required for the period from September 2016 to May 2020. The court is under no deadline to address the appeal.

For more information regarding Ameren Missouris March 2020 electric rate order, the expected acquisition of wind generation facilities by Ameren Missouri, Ameren Illinois electric distribution service formula rate update, and legal proceedings related to the FERC allowed base ROE, see Note 2 Rate and Regulatory Mailers under Part I, Item 1, ofthis report.

RESULTS OF OPERATIONS Our results of operations and financial position are affected by many factors. Economic conditions, including those resulting from the COVID-19 pandemic discussed below, energy-efficiency investments by our customers and by us, technological advances, distributed generation, and the actions of key customers can significantly affect the demand for our services. Ameren and Ameren Missouri results are also affected by seasonal fluctuations in winter heating and summer cooling demands, as well as by non-nuclear energy center maintenance outages. Additionally, fluctuations in interest rates and conditions in the capital and credit markets affect our cost of borrowing, and our pension and postretirement benefits costs.

Almost all of Amerens revenues are subject to state or federal regulation. This regulation has a material impact on the rates we charge customers for our services. Our results of operations, financial position, and liquidity are affected by our ability to align our overall spending, both operating and capital, with the frameworks established by our regulators. See Note 2 Rate and Regulatory Matters under Part I, Item 1, of this report and Note 2 Rate and Regulatory Matters under Part II, Item 8, ofthe Form 1 0-K for additional information regarding Ameren Missouris, Ameren Illinois, and ATXIs regulatory mechanisms.

We continue to assess the impacts ofthe COVID-19 pandemic on our businesses, including impacts on electric and natural gas sales volumes, supply chain operations, and bad debt expense. Ameren Missouri and Ameren Illinois suspended customer disconnections and late fee charges for nonpayment in mid-March 2020 and resumed these activities in the third quarter of 2020. For additional information, see Note 2 Rate and Regulatory Matters under Part I, Item 1, of this report. Regarding uncollectible accounts receivable, Ameren Illinois electric distribution and natural gas distribution businesses have bad debt riders, which provide for recovery of bad debt write-offs, net of any subsequent recoveries. Pursuant to a June 2020 ICC order, Ameren Illinois electric bad debt rider provides for the recovery of bad debt 44

expense in 2020. Ameren Missouri does not have a bad debt rider or regulatory tracking mechanism and its earnings are exposed to increases in bad debt expense. In October 2020, Ameren Missouri filed requests with the MoPSC for accounting authority orders related to costs incurred, net of savings, and forgone customer late fee revenues resulting from the COVID-1 9 pandemic. As of September 30, 2020, accounts receivable balances that were 30 days or greater past due or that were a part of a deferred payment arrangement represented 26%, 18%, and 35%, or $151 million,

$49 million, and $1 02 million, of Amerens, Ameren Missouris, and Ameren Illinois customer trade receivables before allowance for doubtful accounts, respectively. As of September 30, 2019, these percentages were 13%, 9%, and 18%, or $65 million, $23 million, and $42 million, for Ameren, Ameren Missouri, and Ameren Illinois, respectively. Ameren Missouris electric sales volumes have been, and continue to be, affected by the COVID-19 pandemic. In the three and nine months ended September 30, 2020, compared to the same periods in 2019, Ameren Missouri experienced a reduction in commercial and industrial electric sales volumes, partially offset by increased electric sales volumes to higher margin residential customers, excluding the estimated effects ofweather and customer energy-efficiency programs. While the impacts ofthe COVID-19 pandemic are difficult to predict, Ameren Missouri expects the net reduction in sales volumes, excluding the estimated effects of weather and customer energy-efficiency programs, to continue in the fourth quarter of 2020, compared to the same period in 2019. The COVID-19 pandemic may continue to affect Ameren Missouris total electric sales volumes and sales volumes by customer class beyond 2020. Assuming a ratable change in Ameren Missouris electric sales volumes by month, a I % change for the calendar year 2020 to residential, commercial, and industrial customers would affect earnings per diluted share by approximately 3 cents, 2 cents, and a half-cent, respectively. The actual change in earnings per diluted share will be affected by the timing of sales volume changes due to seasonal customer rates. Based on Ameren Missouris current projections, and assuming no significant additional restrictions are placed on individuals and businesses in our service territories, the net decline in electric sales volumes for October 1 through December 31

, 2020, compared to the same period in 201 9, excluding the estimated effects of weather and customer energy-efficiency programs, is expected to result in a decline in earnings per diluted share of approximately I cent. The following table provides the approximate increases and (decreases) in Ameren Missouri electric sales volumes by customer class for the three and nine months ended September 30, 2020, and the estimated changes for the calendar year 2020, compared to the same periods in 201 9, excluding the estimated effects of weather and customer energy-efficiency programs:

QTDYoY YTDYoY CalendarYear(a)

Residential 2.0 %

3.5 %

3.5 Commercial (7.5)%

(7.5)%

(6.5) %

Industrial (O.5)%

(4.O)%

(3.0) %

Total (2.5)%

(2.5)%

(2.0) %

(a) Based on actual results from January 1 through September 30, 2020, and Ameren Missours projection for October 1 through December 31

, 2020, compared to the same periods in 2019.

Ameren Illinois also experienced decreases in electric and natural gas sales volumes in the three and nine months ended September 30, 2020.

However, Ameren Illinois electric distribution and transmission businesses have formula ratemaking frameworks, which provide for recovery of their revenue requirements independent of sales volumes, and Ameren Illinois natural gas distribution business has a VBA, which provides for recovery of the natural gas distribution service revenue requirement associated with sales volumes for residential and small nonresidential customers.

Additionally, ATXIs electric transmission business has a formula ratemaking framework, which provides for recovery of its revenue requirement independent of sales volumes. None of Amerens businesses have experienced significant disruptions to their supply chain operations. However, see Note 2 Rate and Regulatory Mailers under Part I, Item I

, ofthis report for information regarding the impact of supply chain disruptions related to Ameren Missouris acquisition of an up-to 300-megawatt wind generation facility.

Ameren Missouri principally uses coal and enriched uranium for fuel in its electric operations and purchases natural gas for its customers.

Ameren Illinois purchases power and natural gas for its customers. The prices for these commodities can fluctuate significantly because of the global economic and political environment, weather, supply, demand, and many other factors. We have natural gas cost recovery mechanisms for our Illinois and Missouri natural gas distribution businesses, a purchased power cost recovery mechanism for Ameren Illinois electric distribution business, and a FAC for Ameren Missouris electric business.

We employ various risk management strategies to reduce our exposure to commodity risk and other risks inherent in our business. The reliability of Ameren Missouris energy centers and our transmission and distribution systems, and the level and timing of operations and maintenance costs and capital investment, are key factors that we seek to manage in order to optimize our results of operations, financial position, and liquidity.

45

Earnings Summary The following table presents a summary of Amerens earnings for the three and nine months ended September 30, 2020 and 2019:

Three Months Nine Months 2020 2019 2020 2019 Net income attributable to Ameren common shareholders 367 S

364 756 734 Earnings percommon sharediluted 1.47 1.47 3.04 2.97 Net income attributable to Ameren common shareholders increased $3 million, with comparable earnings per diluted share, in the three months ended September 30, 2020, compared with the year-ago period. The increase was due to net income increases of $9 million, $3 million, and $2 million at Ameren Transmission, Ameren Illinois Natural Gas, and Ameren Illinois Electric Distribution, respectively. These increases were partially offset by a net income decrease of $3 million at Ameren Missouri and an $8 million increase in the net loss for activity not reported as part of a segment, primarily at Ameren (parent).

Net income attributable to Ameren common shareholders increased $22 million, or 7 cents per diluted share, in the nine months ended September 30, 2020, compared with the year-ago period. The increase was due to net income increases of $29 million, $9 million, and $2 million at Ameren Transmission, Ameren Illinois Natural Gas, and Ameren Illinois Electric Distribution, respectively. These increases were partially offset by a net income decrease of $7 million at Ameren Missouri and an $1 1 million increase in the net loss for activity not reported as part of a segment, primarily at Ameren (parent).

Earnings per diluted share were favorably affected in the three and nine months ended September 30, 2020, compared to the year-ago periods (except where a specific period is referenced), by:

lower base level of expenses, partially offset by lower base rates, net of recovery for amounts associated with the reduction in sales volumes resulting from MEEIA programs and recoverable depreciation under the PISA, at Ameren Missouri pursuant to the March 2020 MoPSC electric rate order as discussed in Note 2 Rate and Regulatory Matters under Part I, Item 1

, of this report (8 cents and I 5 cents per share, respectively);

increased Ameren Transmission and Ameren Illinois Electric Distribution earnings due to additional rate base investments, including energy-efficiency investments at Ameren Illinois (3 cents and 1 1 cents per share, respectively);

decreased other operations and maintenance expenses related to the absence of a scheduled refueling and maintenance outage at the Callaway Energy Center, which last occurred in the second quarter of 2019 and which costs previously were expensed as incurred, as compared with the deferral of expenses for the fall 2020 refueling and maintenance outage under the February 2020 MoPSC order (1 0 cents per share for the nine months ended September 30, 2020);

decreased other operations and maintenance expenses not subject to riders or regulatory tracking mechanisms, excluding decreased costs associated with the Callaway Energy Centers scheduled refueling and maintenance outage, primarily due to lower electric system infrastructure maintenance expenses as a result of decreased system load, disciplined cost management, and the deferral of projects to future periods, and changes in the cash surrender value of company-owned life insurance, which increased in the three months ended September 30, 2020, but decreased in the nine months ended September 30, 2020 (4 cents and 5 cents per share, respectively);

increased Ameren Transmission earnings resulting from the May 2020 FERC order addressing the allowed base ROE for FERC regulated transmission rate base under the MISO tariff (4 cents per share for the nine months ended September 30, 2020); and increased Ameren Illinois Natural Gas earnings from investments in qualifying infrastructure recovered under the QIP rider (1 cent and 3 cents per share, respectively).

Earnings per diluted share were unfavorably affected in the three and nine months ended September 30, 2020, compared to the year-ago periods (except where a specific period is referenced), by:

lower MEEIA performance incentives recognized at Ameren Missouri (3 cents and 9 cents per share, respectively);

decreased electric retail sales, excluding the estimated effects of weather, at Ameren Missouri due to decreased sales volumes and demand charge revenue from commercial and industrial customers, partially offset by increased sales volumes to higher margin residential customers.

Demand was affected, in part, by the COVID-19 pandemic (2 cents and 8 cents per share, respectively);

decreased electric retail sales at Ameren Missouri due to weather, primarily resulting from milder summer temperatures experienced in 2020 (estimated at 5 cents and 6 cents per share, respectively);

decreased Ameren Illinois Electric Distribution earnings under performance-based formula ratemaking because of a lower recognized ROE driven by lower annual average monthly yields on 30-year United States Treasury bonds (1 cent and 5 cents per share, respectively);

increased net financing costs primarily at Ameren (parent), primarily because of its April 2020 debt issuance (3 cents and 5 cents per share, respectively);

46

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Below is Amerens table of income statement components by segment for the three and nine months ended September 30, 2020 and 2019:

Ameren Illinois Ameren Other!

Ameren Electric Illinois Ameren Intersegment Missouri Distribution Natural Gas Transmission Eliminations Ameren Three Months 2020:

Electric margins 795 279

141 (7) 1,208 Natural gas margins 12

93

105 Other operations and maintenance expenses (221)

(133)

(52)

(14) 2 (418)

Depreciation and amortization expenses (154)

(71)

(21)

(25)

(2)

(273)

Taxes other than income taxes (92)

(21)

(1 1)

(2)

(2)

(128)

Other income, net 26 9

4 4

5 48 Interest charges (50)

(19)

(10)

(19)

(12)

(110)

Income taxes (18)

(10)

(1)

(22)

(12)

(63)

Net income (loss) 298 34 2

63 (28) 369 Noncontrolling interests preferred stock dividends (1)

(1)

(2)

Net income (loss) attributable to Ameren common shareholders 297 34 2

62 (28) 367 Three Months 2019:

Electric margins 844 270

128 (9) 1,233 Natural gas margins 13

87

100 Other operations and maintenance expenses (242)

(1 28)

(52)

(1 5) 3 (434)

Depreciation and amortization expenses (138)

(68)

(20)

(21)

(1)

(248)

Taxes otherthan income taxes (96)

(22)

(10)

(1)

(2)

(131)

Other income, net 15 9

3 2

5 34 Interest charges (44)

(1 9)

(9)

(20)

(4)

(96)

Income taxes (51)

(10)

(19)

(12)

(92)

Net income (loss) 301 32 (1) 54 (20) 366 Noncontrolling interests preferred stock dividends (1)

(1)

(2)

Net income (loss) attributable to Ameren common shareholders 300 32 (1) 53 (20) 364 Nine Months 2020:

Electric margins I 862 823

400 (22) 3,063 Natural gas margins 58

379

437 Other operations and maintenance expenses (662)

(381 )

(1 61 )

(43) 7 (1,240)

Depreciation and amortization expenses (448)

(21 3)

(62)

(72)

(4)

(799)

Taxes other than income taxes (254)

(59)

(46)

(6)

(7)

(372)

Other income, net 55 25 1 1 9

1 7 117 Interest charges (140)

(55)

(30)

(58)

(28)

(311)

Income (taxes) benefit (29)

(32)

(24)

(61) 12 (134)

Net income (loss) 442 108 67 169 (25) 761 Noncontrolling interests preferred stock dividends (3)

(1 )

(1 )

(1 )

I (5)

Net income (loss) attributable to Ameren common shareholders 439 107 66 168 (24) 756 Nine Months 2019:

Electric margins I 948 804

351 (24) 3,079 Natural gas margins 57

373

430 Other operations and maintenance expenses (720)

(373)

(170)

(44) 6 (1,301)

Depreciation and amortization expenses (417)

(204)

(59)

(62)

(3)

(745)

Taxes other than income taxes (256)

(61 )

(47)

(3)

(8)

(375)

Other income, net 43 25 9

6 16 99 Interest charges (136)

(54)

(28)

(58)

(14)

(290)

Income (taxes) benefit (70)

(31)

(20)

(50) 13 (158)

Net income (loss) 449 106 58 140 (14) 739 Noncontrolling interests preferred stock dividends (3)

(1)

(1)

(1) 1 (5)

Net income (loss) attributable to Ameren common shareholders 446 I 05 57 I 39 (1 3) 734 48

Below is Ameren Illinois table of income statement components by segment for the three and nine months ended September 30, 2020 and 2019:

Ameren Illinois Ameren Ameren Electric Illinois liNnois Distribution Natural Gas Transmission Ameren Illinois Three Months 2020:

Electric and natural gas margins 279 93 91 463 Other operations and maintenance expenses (133)

(52)

(12)

(197)

Depreciation and amortization expenses (71)

(21)

(17)

(109)

Taxesotherthanincometaxes (21)

(11)

(1)

(33)

Other income, net 9

4 4

17 Interest charges (19)

(10)

(10)

(39)

Incometaxes (10)

(1)

(14)

(25)

Net income attributable to common shareholder 34 2

41 77 Three Months 2019:

Electric and natural gas margins 270 87 81 438 Other operations and maintenance expenses (128)

(52)

(13)

(193)

Depreciation and amortization expenses (68)

(20)

(14)

(102)

Taxesotherthanincometaxes (22)

(10)

(1)

(33)

Other income, net 9

3 1

13 lnterestcharges (19)

(9)

(10)

(38)

Income taxes (10)

(10)

(20)

Net income (loss) attributable to common shareholder 32 (1) 34 65 Nine Months 2020:

Electric and natural gas margins 823 379 252 1,454 Other operations and maintenance expenses (381)

(161)

(36)

(578)

Depreciation and amortization expenses (213)

(62)

(48)

(323)

Taxes other than income taxes (59)

(46)

(2)

(107)

Otherincome, net 25 11 9

45 Interest charges (55)

(30)

(31)

(116)

Income taxes (32)

(24)

(37)

(93)

Netincome 108 67 107 282 Preferred stock dividends (1 )

(1 )

(2)

Net income attributable to common shareholder 107 66 107 280 Nine Months 2019:

Electric and natural gas margins 804 373 217 1,394 Other operations and maintenance expenses (373)

(170)

(37)

(580)

Depreciation and amortization expenses (204)

(59)

(41)

(304)

Taxes other than income taxes (61 )

(47)

(2)

(110)

Other income, net 25 9

5 39 Interest charges (54)

(28)

(29)

(111)

Income taxes (31)

(20)

(28)

(79)

Netincome 106 58 85 249 Preferred stock dividends (1)

(1)

(2)

Net income attributable to common shareholder I 05 57 85 247 Electric and Natural Gas Margins Electric margins are defined as electric revenues less fuel and purchased power costs. Natural gas margins are defined as natural gas revenues less natural gas purchased for resale. We consider electric and natural gas margins useful measures to analyze the change in profitability of our electric and natural gas operations between periods. We have included the analysis below to complement the financial information we provide in accordance with GAAP. However, these margins may not be a presentation defined under GAAP, and they may not be comparable to other companies presentations or more useful than the GAAP information we provide elsewhere in this report.

49

Electric Margins Total by Segment(a) 52000 0

$t208 5tDG sa

$3O63

$3O79 1I I

QTD QTD YTD 2020 2019 2020 Increase (Decrease) by Segment Overall Ameren Overall Ameren Decrease of $25 Million Decrease of $16 Million (QID Y0Y)

(YTD YoY)

(a)

Includes other/intersegment eliminations of $(7) million and $(9) million in the three months ended September 30, 2020, and 201 9, respectively. Also includes other/intersegment eliminations of $(22) million and $(24) million in the nine months ended September 30, 2020, and 201 9, respectively.

IAmeren Missouri I

Ameren Illinois Electric Ameren Transmission Distribution Other/Intersegment Eliminations Natural Gas Margins

$105 sioo

$100

][ -f 550 10 QTD QID YTD 2020 2019 2020

$3500

$3DG0

$2500

$20

$13

$9 549

$2

$79

$0 1(50) 1(20) 1(40)

YTD 2019 5(60) 5(100)

Total by Segment 37

$430

$8 Increase (Decrease) by Segment Overall Ameren Overall Ameren Increase Increase of $5 Million of $7 Million (YTD YoY)

(QTD Y0Y)

$350

$300

$250 4

$81

$6 54-

$2 10 52 no 2019 Ameren Missouri 1(2)

Ameren Illinois Natural Gas

$0 50

The following tables present the favorable (unfavorable) variations by Ameren segment for electric and natural gas margins for the three and nine months ended September 30, 2020, compared with the year-ago periods:

Ameren Illinois Ameren Other Ameren Electric Illinois Ameren Ilntersegment Three Months Missouri Distribution Natural Gas Transmission(a)

Eliminations Ameren Electric revenue change:

Effect of weathe (estimate)fb)

(23)

(23)

Base rates (estimate)(c)

(34) 1

1 3

(20)

Sales volumes and changes in customer usage patterns (excluding the estimated effects ofweather and MEEIA)

(7)

(7)

Customer demand charges (4)

(4)

MEEIA 2013, MEEIA 2016, and MEEIA 2019 performance incentives (11)

(11) 0ff-system sales 33

33 Energy-efficiency program investments

2

2 Other

3

2 5

Cost recovery mechanisms offset in fuel and purchased power(d)

(6)

(6)

Other cost recovery mechanismsfe)

( 0) 2

(8)

Total electric revenue change (56) 2

13 2

(39)

Fuel and purchased power change:

Energy costs (excluding the estimated effect of weather)

(29)

(29)

Effect of weather (estimate)(b) 5 5

Effect of lower net energy costs included in base rates 32

32 Transmission services charges (1)

(1)

Other

I

1 Cost recovery mechanisms offset in electric revenue(d) 6

6 Total fuel and purchased power change S

7 7

14 Net change in electric margins (49) 9

13 2

(25)

Natural gas revenue change:

QIP rider

6

6 Software licensing agreement

(5)

(5)

Other (1)

4

3 Cost recovery mechanisms offset in natural gas purchased for resale(d)

(1 )

4

3 Other cost recovery mechanisms(e)

I

I Total natural gas revenue change (2)

10

8 Natural gas purchased for resale change:

Cost recovery mechanisms offset in natural gas revenue(d) 1

(4)

(3)

Total natural gas purchased for resale change 1

(4)

(3)

Net change in natural gas margins (1)

6

5 51

Ameren Ameren Illinois Illinois Other Ameren Electric Natural Ameren Ilntersegment Nine Months Missouri Distribution Gas Transmission(a)

Eliminations Ameren Electric revenue change:

Effect of weather (estimate)(b)

(29)

(29)

Base rates (estimate)(c)

(51) 5

49

3 Sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA)

(33)

(33)

Customer demand charges (5)

(5)

MEEIA 2013, MEEIA 2016, and MEEIA 2019 performance incentives (32)

(32) 0ff-system sales 33

33 Customer late fees and reconnection fees (4)

(4)

Energy-efficiency program investments

8

8 Other (3) 4

2 3

Cost recovery mechanisms offset in fuel and purchased power(d)

(1)

(20)

(21)

Other cost recovery mechanisms(e)

(6) 1

(5)

Total electric revenue change (131)

(2)

49 2

(82)

Fuel and purchased power change:

Energy costs (excluding the estimated effect ofweather)

(21)

(21)

Effect of weather (estimate)(b) 9 9

Effect of lower net energy costs included in base rates 61

61 Transmission services charges (3)

(3)

Other (2) 1

(1)

Cost recovery mechanisms offset in electric revenue(d)

I 20

21 Total fuel and purchased power change 45 21

66 Net change in electric margins (86) 19

49 2

(16)

Natural gas revenue change:

Effect of weather (estimate)(b)

(2)

(2)

QiPrider

16

16 Software licensing agreement

(5)

(5)

Other 2

2

4 Cost recovery mechanisms offset in natural gas purchased for resale(d)

(11)

(41)

(52)

Other cost recovery mechanisms(e)

(7)

(7)

Totalnaturalgasrevenuechange (11)

(35)

(46)

Natural gas purchased for resale change:

Effect of weather (estimate)(b) 1

1 Cost recovery mechanisms offset in natural gas revenue(d) 1 1

41

52 Total natural gas purchased for resale change 1 2

41

53 Netchangeinnaturalgasmargins I

6

7 (a)

Includes an increase in transmission margins of $1 0 million and $35 million at Ameren Illinois for the three and nine months ended September 30, 2020, compared with the year-ago periods.

(b)

Represents the estimated variation resulting primarily from changes in cooling and heating degree-days on electric and natural gas demand compared with the year-ago periods; this variation is based on temperature readings from the National Oceanic and Atmospheric Administration weather stations at local airports in our service territories.

(c)

For Ameren Illinois Electric Distribution and Ameren Transmission, base rates include increases or decreases to operating revenues related to the revenue requirement reconciliation adjustment under formula rates. For Ameren Missouri, base rates exclude an increase of $23 million and $35 million for the recovery of lost electric margins forthe three and nine months ended September 30, 2020, respectively, compared with the year-ago periods, resulting from the MEEIA 2016 and 2019 customer energy-efficiency programs. This amount is included in the sales volumes and changes in customer usage patterns (excluding the estimated effects of weather and MEEIA) line item.

(d)

Electric and natural gas revenue changes are offset by corresponding changes in Fuel, Purchased power, and Natural gas purchased for resale on the statement of income, resulting in no change to electric and natural gas margins.

(e)

Offsetting expense increases or decreases are reflected in Other operations and maintenance, Depreciation and amortization, or in Taxes other than income taxes, within the Operating Expenses section and Income Taxes in the statement of income. These items have no overall impact on earnings.

52

Ameren Amerens electric margins decreased $25 million, or 2%, and $16 million, or I %, for the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods, primarily because of decreased margins at Ameren Missouri, partially offset by increased margins at Ameren Transmission and Ameren Illinois Electric Distribution, as discussed below.

Amerens natural gas margins increased $5 million, or 5%, and $7 million, or 2%, for the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods, primarily because of increased margins at Ameren Illinois Natural Gas, as discussed below.

Ameren Transmission Ameren Transmissions margins increased $13 million, or 10%, and $49 million, or 14%, for the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods. Base rate revenues were favorably affected by increased capital investment, as evidenced by a 13% increase in rate base used to calculate the revenue requirement, and an increase in the allowed ROE resulting from the May 2020 FERC order. See Note 2 Rate and Regulatory Mailers under Part I, Item 1, of this report for additional information regarding the FERC complaint cases.

Ameren Missouri Ameren Missouris electric margins decreased $49 million, or 6%, and $86 million, or 4%, for the three and nine months ended September 30, 2020, respectively, compared with the year ago periods.

The following items had an unfavorable effect on Ameren Missouris electric margins for the three and nine months ended September 30, 2020, compared with the year-ago periods (except when a specific period is referenced):

The aggregate effect of changes in customer usage, excluding the estimated effects of weather and the MEEIA customer energy-efficiency programs, decreased electric revenues an estimated $1 1 million and $38 million, respectively. The decrease was primarily due to a reduction in sales volumes (-$18 million and -$37 million, respectively) and decreased revenues from customer demand charges (-$4 million and -$5 million, respectively), both of which were unfavorably affected by the COVID-1 9 pandemic. An increase in the average retail price per kilowatthour due to changes in customer usage patterns partially offset the decreases by +$1 1 million and +$4 million, respectively. While the MEEIA customer energy-efficiency programs reduced retail sales volumes, the recovery of lost electric margins under the MEEIA ensured that electric margins were not affected.

The absence of revenues associated with MEEIA 2013 and 2016 performance incentives in 2020, partially offset by revenues from the MEEIA 2019 performance incentive, decreased revenues $11 million and $32 million, respectively. See Note 2 Rate and Regulatory Matters under Part I, Item I, of this report for information regarding the MEEIA performance incentives.

Summer temperatures were milder as cooling degree days decreased 14% and 8%, respectively, and winter temperatures were warmer as heating degree days decreased 9% for the nine months ended September 30, 2020. The aggregate effect of weather decreased margins an estimated $1 8 million and $20 million, respectively. The change in margins due to weather is the sum of the effect of weather (estimate) on electric revenues (-$23 million and -$29 million, respectively) and the effect of weather (estimate) on fuel and purchased power (+$5 million and

+$9 million, respectively) in the table above.

The COVID-19 pandemic caused the suspension of customer late fees and disconnections, which decreased revenues $4 million for the nine months ended September 30, 2020. See Note 2 Rate and Regulatory Matters under Part I, Item 1, of this report for information on the suspension of customer late fees and disconnections.

The following items had a favorable effect on Ameren Missouris electric margins for the three and nine months ended September 30, 2020, compared with the year-ago periods (except when a specific period is referenced):

Lower net energy costs increased margins $4 million and $12 million, respectively, as a result of decreased sales volumes, which were reduced by the COVID-19 pandemic. The change in net energy costs is the sum ofthe effect of revenue change in off-system sales (+$33 million and

+$33 million, respectively), and the effect of the change in energy costs (-$29 million and -$21 million, respectively) in the table above.

Lower net energy costs included in base rates partially offset by lower electric base rates as a result of the March 2020 MoPSC electric rate order, with new rates effective April 1, 2020, increased margins $1 0 million for the nine months ended September 30, 2020. The change in electric base rates is the sum of the change in base rates (estimate) (-$51 million) and the effect of lower net energy costs included in base rates (+$61 million) in the table above.

Ameren Missouris natural gas margins were comparable between periods.

53

Ameren Illinois Ameren Illinois electric margins increased $19 million, or 5%, and $54 million, or 5%, for the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods, driven by increased margins at Ameren Illinois Transmission and Ameren Illinois Electric Distribution. Ameren Illinois Natural Gas margins increased $6 million, or 7%, and $6 million or 2%, respectively, for the three and nine months ended September 30, 2020, compared with the year-ago periods.

Ameren Illinois Electric Distribution Ameren Illinois Electric Distributions margins increased $9 million, or 3%, and $1 9 million, or 2%, for the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods. The following items had a favorable effect on Ameren Illinois Electric Distributions margins for the three and nine months ended September 30, 2020, compared with the year-ago periods (except when a specific period is referenced):

Margins increased due to higher recoverable non-purchased power expenses (+$10 million) and increased capital investment (+$8 million), as evidenced by a 8% increase in rate base used to calculate the revenue requirement, partially offset by a lower recognized ROE (-$13 million),

as evidenced by a decrease of 100 basis points in the estimated annual average ofthe monthly yields ofthe 30-year United States Treasury bonds under performance-based formula ratemaking for the nine months ended September 30, 2020. The sum of these changes collectively increased margins $5 million for the nine months ended September 30, 2020.

Revenues increased $2 million and $8 million, respectively, due to recovery of increased energy-efficiency program investments under performance-based formula ratemaking.

Ameren Illinois Natural Gas Ameren Illinois Natural Gas margins increased $6 million, or 7%, and $6 million or 2%, for the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods. Revenues increased from QIP recoveries due to additional investment in qualified natural gas infrastructure increased margins $6 million and $16 million, for the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods. The absence of revenues from a 201 9 software licensing agreement with Ameren Missouri decreased margins $5 million for the three and nine months ended September 30, 2020, compared with the year-ago periods. See Note 8

- Related-party Transactions under Part I, Item 1

, of this report for additional information.

Ameren Illinois Transmission Ameren Illinois Transmissions margins increased $10 million, or 12%, and $35 million, or 16%, for the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods. Margins were favorably affected by increased capital investment, as evidenced by a 18% increase in rate base used to calculate the revenue requirement, and an increase in the allowed ROE resulting from the May 2020 FERC order. See Note 2 Rate and Regulatory Matters under Part I, Item 1

, of this report for additional information regarding the FERC complaint cases.

54

Other Operations and Maintenance Expenses

$10 S.(1O)

• Sf9)

S2O)

S3O)

S4O)

S5O)

S6O)

$(SB)

$(7O)

(a)

Includes $14 million and $1 5 million of other operations and maintenance at Ameren Transmission in the three months ended September 30, 2020 and 2019, respectively. Includes other/intersegment eliminations of $(2) million and $(3) million in the three months ended September 30, 2020, and 201 9, respectively. Also includes other/intersegment eliminations of $(7) million and $(6) million in the nine months ended September 30, 2020, and 2019, respectively.

Ameren Missouri UAmeren Illinois Natural Gas Other/lntersegment Eliminations I

AmerenWinois Electric lAmeren Transmission Ameren Other operations and maintenance expenses decreased $16 million and $61 million in the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods, due to changes discussed below.

Ameren Transmission Other operations and maintenance expenses were comparable between periods.

Ameren Missouri Other operations and maintenance expenses decreased $21 million and $58 million in the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods. The following items decreased other operations and maintenance expenses in the three and nine months ended September 30, 2020, compared with the year-ago periods (except where a specific period is referenced):

Callaway Energy Center refueling operations and maintenance costs decreased $34 million in the nine months ended September 30, 2020, primarily because of the refueling and maintenance outage that was completed in May 201 9. The 201 9 outage costs were expensed as incurred. Costs for the current years fall refueling and maintenance outage are being deferred as a regulatory asset pursuant to the February 2020 MoPSC order.

Energy center maintenance costs, other than those associated with the Callaway refueling and maintenance outage, decreased $6 million and

$21 million, respectively, primarily due to lower electric system infrastructure maintenance expenses as a result of decreased system load, disciplined cost management, and the deferral of projects to future periods.

Transmission and distribution expenditures decreased $6 million and $1 1 million, respectively, primarily due to increased labor directed towards capital projects versus operations and maintenance-oriented projects. The decrease in the three months ended September 30, 2020, was partially offset by increased storm costs in the current year period.

$1,40 Total by Segment(a)

Increase (Decrease) by Segment Overall Ameren Decrease of $16 Million (QTD YoY) 510

$1,000

£5 Overall Ameren Decrease of $61 Million (YTD YoY)

$8 So

$1

$1)

$200 So S20)

QTD QID YTD YTO 2020 2019 2020 2019 5(30) 55

Amortization of solar rebate costs incurred prior to the RESRAM decreased $5 million and $9 million, respectively, as a result of the March 2020 MoPSC electric rate order.

The cash surrender value of company-owned life insurance increased $4 million in the three months ended September 30, 2020, because of favorable market returns in the current-year period.

Customer energy-efficiency program costs decreased $3 million in the three months ended September 30, 2020, because of increased participation in the MEEIA 2019 programs in the third quarter of 2019.

The following items partially offset the above decreases in other operations and maintenance expenses in the three and nine months ended September 30, 2020, compared with the year-ago periods (except where a specific period is referenced):

Solar rebate costs recoverable under the RESRAM resulted in increased expenses of $3 million and $7 million, respectively.

Technology-related expenditures increased $6 million in the nine months ended September 30, 2020, primarily due to costs associated with the implementation of cloud computing technology.

The cash surrender value of company-owned life insurance decreased $5 million in the nine months ended September 30, 2020, because of less favorable market returns in the current-year period, compared with the year-ago period.

Ameren Illinois Other operations and maintenance expenses increased $4 million and decreased $2 million in the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods, as discussed below. Other operations and maintenance expenses were comparable between periods at Ameren Illinois Transmission.

Ameren Illinois Electric Distribution Other operations and maintenance expenses increased $5 million and $8 million in the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods. The following items increased other operation and maintenance expenses in the three and nine months ended September 30, 2020, compared with the year-ago periods (except where a specific period is referenced):

Amortization of regulatory assets associated with energy-efficiency program investments under performance-based formula ratemaking increased $5 million in the nine months ended September 30, 2020.

Labor and benefits increased $4 million and $5 million, respectively, including an increase in power restoration assistance provided to other utilities.

The cash surrender value of company-owned life insurance decreased $2 million in the nine months ended September 30, 2020, because of less favorable market returns in the current-year period, compared with the year-ago period.

Environmental remediation rider costs increased $2 million in the three months ended September 30, 2020, due to timing of projects.

The following items partially offset the above increases in other operations and maintenance expenses in the three and nine months ended September 30, 2020 compared with the year-ago periods (except where a specific period is referenced):

Meter reading costs decreased $4 million in the nine months ended September 30, 2020, as Ameren Illinois Electric Distribution completed deployment of automated smart meters in 2019.

The cash surrender value of company-owned life insurance increased $2 million in the three months ended September 30, 2020, resulting from favorable market returns in the current-year period.

Ameren Illinois Natural Gas Other operations and maintenance expenses were comparable between the three months ended September 30, 2020, and the year-ago period.

Other operations and maintenance expenses decreased $9 million in the nine months ended September 30, 2020, compared with the year-ago period, primarily because of a $4 million reduction in energy-efficiency rider costs due to the deferral of projects to future periods and a $3 million reduction in meter reading costs as Ameren Illinois Natural Gas completed deployment of automated smart meters in 2019.

56

Depreciation and Amortization Expenses Increase (Decrease) by Segment Overall Ameren Increase of $25 Million (QTD YoY)

Ameren Missouri I

Ameren Illinois Electric Distribution Ameren Illinois Natural Gas Ameren Transmission Other/Intersegment Eliminations Depreciation and amortization expenses increased $25 million, $16 million, and $7 million in the three months ended September 30, 2020, and

$54 million, $31 million, and $19 million in the nine months ended September 30, 2020, compared with the year-ago periods, at Ameren, Ameren Missouri, and Ameren Illinois, respectively, primarily because of additional property, plant, and equipment investments across their respective segments. Amerens and Ameren Missouris depreciation and amortization expenses reflect a deferral to a regulatory asset of depreciation and amortization expenses pursuant to the PISA. As a result of the March 2020 MoPSC electric rate order, the deferral to a regulatory asset of depreciation and amortization expenses related to PISA-eligible assets placed in-service through December 31

, 2019, ceased as of April 1, 2020, as the associated depreciation and amortization expenses were then reflected in customer rates. The PISA deferral of depreciation and amortization expenses was $3 million and $7 million for the three months ended September 30, 2020 and 2019, respectively, and $17 million and $14 million for the nine months ended September 30, 2020 and 2019, respectively.

Total by Segment(a)

$20

$900

$700

$600

$500 0

4,)

Overall Ameren Increase of $54 Million (YTD YoY) 140

$16

$31 sao

$300

$273 5248t

$200

$100

$0

$20 QTD OlD TD frD 2020 2019 2020 2019

$4

$10

$0 5.9 10 LI (a)

Includes $25 million and $21 million of depreciation and amortization expense at Ameren Transmission in the three months ended September 30, 2020 and 2019, respectively. Includes other/intersegment eliminations of $2 million and $1 million in the three months ended September 30, 2020, and 201 9, respectively. Also includes other/intersegment eliminations of $4 million and $3 million in the nine months ended September 30, 2020, and 2019, respectively.

57

Taxes Other Than Income Taxes Total by Segment(a)

Increase (Decrease) by Segment Overall Ameren Overall Ameren Decrease of $3 Million Decrease of (QTD Y0Y)

$3 Million (YTD YoY)

(a)

Includes $2 million, $1 million, $6 million, and $3 million at Ameren Transmission in the three months ended September 30, 2020, the three months ended September 30, 201 9, the nine months ended September 30, 2020, and the nine months ended September 30, 201 9, respectively, and other/intersegment eliminations of $2 million, $2 million, $7 million, and $8 million, in the three months ended September 30, 2020, the three months ended September 30, 201 9, the nine months ended September 30, 2020, and the nine months ended September 30, 2019, respectively.

.Ameren Missouri Ameren Illinois Natural Gas I

Electric lAmeren Transmission Other/Intersegment Eliminations Taxes other than income taxes decreased $3 million in the three months ended September 30, 2020, compared with the year-ago period, primarily due to a decrease in excise taxes at Ameren Missouri as a result of reduced sales, as discussed in the Electric and Natural Gas Margins section above. Taxes other than income taxes decreased $3 million in the nine months ended September 30, 2020, compared with the year-ago period, primarily due to a $7 million decrease in excise taxes at Ameren Missouri and a $2 million reduction in the electric distribution tax at Ameren Illinois Electric Distribution, both as a result of reduced sales. These decreases were partially offset by property tax increases of $4 million and $3 million at Ameren Missouri and Ameren Transmission, respectively, resulting from higher assessed values.

$372

$375 j4

$4

$3

$2

$400

$350

$300

$250 U,

C0

$200 4,

$150

$128 S131

$100

$50

$0

$1 SI

$1 I0

$(1)

$11)

$2) wiI 52i 512)

$(3)

$4)

$3)

QTD OTO YTD YTO 2020 2019 2020 2019

$4)

${5) 58

Other Income, Net Increase (Decrease) by Segment Overall Ameren Increase of $14 Million (QTD Y0Y)

.Ameren Missouri Ameren Illinois Natural Gas

• Other/Intersegment Eliminations I

Electric lAmeren Transmission (a)

Includes $4 million and $2 million of other income, net, at Ameren Transmission in the three months ended September 30, 2020 and 201 9, respectively.

Other income, net, increased $14 million in the three months ended September 30, 2020, compared with the year-ago period, primarily due to a

$9 million increase in the non-service cost components of net periodic benefit income at Ameren Missouri, partially due to changes in the base level of pension and postretirement costs as a result of the March 2020 MoPSC electric rate order. Additionally, other income, net, increased due to a $3 million increase in the equity portion of allowance for funds used during construction at Ameren Transmission, primarily due to lower short-term borrowings in the current-year period. Other income, net, increased $18 million in the nine months ended September 30, 2020, compared with the year-ago period. An increase of $1 9 million in the non-service cost components of net periodic benefit income at Ameren Missouri was partially offset by a $6 million increase in donations, primarily due to charitable donations made pursuant to the March 2020 MoPSC electric rate order.

Additionally, other income, net, increased due to a $3 million increase in the equity portion of allowance for funds used during construction at Ameren Transmission. See Note 2 Rate and Regulatory Mailers under Part I, Item I

, of this report for additional information regarding the Ameren Missouris March 2020 electric rate order.

See Note 5 Other Income, Net under Part I, Item 1

, of this report for additional information.

$120 Total by Segment(a)

$140

$15

$10

$IGO Overall Ameren Increase of $1 8 Million (YTD YoY)

CC Si I

$12

$60 54

$20 I0

$5

$15

$10

$5

$0 QTD QTO YfD (TO 2020 2019 2020 2019

$2 so

$3 59

Interest Charges

$96 QTD 010 2020 2019 aAmeren Missouri SAmeren Illinois Natural Gas Other/lntersegment Eliminations I

Amerenflhnois Electric lAmeren Transmission (a)

Includes other/intersegment eliminations of $1 2 million and $4 million of other income, net, in the three months ended September 30, 2020 and 201 9, respectively.

Interest charges increased $14 million and $21 million in the three and nine months ended September 30, 2020, respectively, compared with the year-ago periods, primarily due to a long-term debt issuance at Ameren (parent) in April 2020, which increased interest charges by $7 million and

$14 million, respectively, and a long-term debt issuance at Ameren Missouri in March 2020, which increased interest charges by $3 million and $7 million, respectively. Lower PISA deferrals also resulted in increased interest charges at Ameren Missouri in the three months ended September 30, 2020. Interest charges at Ameren and Ameren Missouri reflect a deferral to a regulatory asset of interest charges pursuant to PISA. As a result of the March 2020 MoPSC electric rate order, the deferral to a regulatory asset of amounts related to PISA-eligible assets placed in-service through December 31

, 201 9, ceased as of April 1, 2020, as the return on those PISA assets was then reflected in customer rates. The PISA deferral of interest charges was less than $1 million and $4 million for the three months ended September 30, 2020 and 2019, respectively, and $9 million for each of the nine months ended September 30, 2020 and 2019.

Income Taxes The following table presents effective income tax rates for the three and nine months ended September 30, 2020 and 2019:

Three Months(a)

Nine Months(a) 2020 2019 2020 2019 Ameren 15 %

20 15%

18%

Ameren Missouri 6 %

14 6 %

13 %

Ameren Illinois 24 %

24 25 %

24 %

Ameren Illinois Electric Distribution 21 23 23 %

23 %

Ameren Illinois Natural Gas (b)

(b) 26 %

26 %

Ameren Illinois Transmission 25 %

24 26 %

25 %

Ameren Transmission 26 %

25 27 %

26 %

(a)

Estimate of the annual effective income tax rate adjusted to reflect the tax effect of items discrete to the three and nine months ended September 30, 2020 and 2019.

(b)

Not meaningful because of the insignificant amount of income before income taxes.

See Note 12 Income Taxes under Part I, Item I, of this report for a reconciliation of the federal statutory corporate income tax rate to the effective income tax rate for the Ameren Companies.

Total by Segment Increase (Decrease) by Segment Overall Ameren Increase of $14 Million (OlD YoY)

$311

$10

$350

$3O

$250

$20 0

z;siso

$110

$5 Overall Ameren Increase of $21 Million (YTD YoY)

$15 514

$10 j.IJ

$(1)

YTD YTO 2020 2019

$(5) 60

The effective income tax rate was lower at Ameren Illinois Electric Distribution in the three months ended September 30, 2020, compared with the year-ago period, primarily because of lower amortization of excess deferred taxes and lower tax benefits from certain depreciation differences on property-related items largely attributable to the allowance for equity funds used during construction.

LIQUIDITY AND CAPITAL RESOURCES Collections from our tariff-based revenues are our principal source of cash provided by operating activities. A diversified retail customer mix, primarily consisting of rate-regulated residential, commercial, and industrial customers, provides us with a reasonably predictable source of cash. In addition to using cash provided by operating activities, we use available cash, drawings under committed credit agreements, commercial paper issuances, and/or, in the case ofAmeren Missouri and Ameren Illinois, short-term affiliate borrowings to support normal operations and temporary capital requirements. We may reduce our short-term borrowings with cash provided by operations or, at our discretion, with long-term borrowings, or, in the case of Ameren Missouri and Ameren Illinois, with capital contributions from Ameren (parent). We expect to make significant capital expenditures over the next five years as we invest in our electric and natural gas utility infrastructure to support overall system reliability, grid modernization, renewable energy requirements, environmental compliance, and other improvements. As part of its plan to fund these cash flow requirements, Ameren is using newly issued shares of common stock, rather than market-purchased shares, to satisfy requirements under the DRPIus and employee benefit plans and expects to continue to do so through at least 2024. Ameren expects these issuances to provide equity of about $100 million annually. Ameren also plans to issue incremental common equity to fund a portion ofAmeren Missouris wind generation investments through the physical settlement of the forward sale agreement entered into in August 201 9 relating to 7.5 million shares of common stock. Additionally, Ameren plans to issue incremental equity of about $150 million annually from 2021 to 2024. Incremental renewable generation investment opportunities included in Ameren Missouris 2020 IRP may result in the need for additional equity. For additional information about the forward sale agreement, see Note 4 Long-Term Debt and Equity Financings under Part I, Item I

, of this report. Ameren expects its equity to total capitalization to be about 45% through the period ending December 2024, with the long-term intent to support solid investment-grade credit ratings.

The use of cash provided by operating activities and short-term borrowings to fund capital expenditures and other long-term investments at the Ameren Companies frequently results in a working capital deficit, defined as current liabilities exceeding current assets, as was the case at September 30, 2020, for Ameren and Ameren Illinois. With the credit capacity available under the Credit Agreements, and cash and cash equivalents, Ameren (parent), Ameren Missouri, and Ameren Illinois, collectively, had net available liquidity of $2.0 billion at September 30, 2020. As a result of capital market volatility, due, in part, to the COVID-19 pandemic, and to increase net available liquidity, Ameren (parent) accelerated a debt issuance to April 2020, which had been planned for later in 2020, and used a portion of the proceeds to repay $350 million of senior unsecured notes held by Ameren (parent) in October 2020. Additionally, Ameren expects to receive between $540 million and $550 million upon settlement of the forward sale agreement, which can be settled at Amerens discretion on or prior to March 31

, 2021

. See Credit Facility Borrowings and Liquidity and Long-term Debt and Equity below for additional information.

The following table presents net cash provided by (used in) operating, investing, and financing activities for the nine months ended September 30, 2020 and 2019:

Net Cash Provided By Net Cash Used In Net Cash Provided by (Used in)

Operating Activities Investing Activities Financing Activities 2020 2019 Variance 2020 2019 Variance 2020 2019 Variance Ameren 1,329 1,668 (339)

(1,981)

(1,798)

(183) 644 178 466 Ameren Missouri 709 840 (131)

(877)

(785)

(92) 139 (49) 188 Ameren Illinois 515 706 (191)

(1,030)

(903)

(127) 537 234 303 Cash Flows from Operating Activities Our cash provided by operating activities is affected by fluctuations of trade accounts receivable, inventories, and accounts and wages payable, among other things, as well as the unique regulatory environment for each of our businesses. Substantially all expenditures related to fuel, purchased power, and natural gas purchased for resale are recovered from customers through rate adjustment mechanisms, which may be adjusted without a traditional rate proceeding. Similar regulatory mechanisms exist for certain other operating expenses that can also affect the timing of cash provided by operating activities. The timing of cash payments for costs recoverable under our regulatory mechanisms differs from the recovery period of those costs. Additionally, the seasonality of our electric and natural gas businesses, primarily caused by seasonal customer rates and changes in customer demand due to weather, significantly affects the amount and timing of our cash provided by operating activities.

Our customers payment for our services has been adversely affected by the COVID-19 pandemic, resulting in a decrease to our cash flow from operations. For information regarding Ameren Missouris and Ameren Illinois suspension and subsequent reinstatement of customer disconnection activities and late fee charges for nonpayment, see Note 2 Rate and Regulatory Matters under Part I, Item I

, of this report. In addition, see Results of Operations above for more information on Amerens, Ameren Missouris, and Ameren Illinois accounts receivable balances that were 30 days or greater past due or that were a part of a deferred payment arrangement.

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Ameren Amerens cash provided by operating activities decreased $339 million in the first nine months of 2020, compared with the year-ago period. The following items contributed to the decrease:

A $281 million decrease resulting from decreased customer collections, primarily due to an increase in accounts receivable balances, which reflected an increase in amounts that were 30 days or greater past due or that were a part of a deferred payment arrangement, a decrease in sales volumes and a net decrease attributable to regulatory recovery mechanisms, partially offset by decreased fuel and purchased power costs at Ameren Missouri and decreased purchased power costs and volumes and natural gas costs at Ameren Illinois.

A $40 million decrease, primarily resulting from increases to materials and supplies to support operations as levels were increased to mitigate against any potential supply disruptions.

A $32 million increase in payments to settle ARO liabilities, primarily related to Ameren Missouris CCR storage facilities.

A $27 million increase in pension and postretirement benefit plan contributions.

A $25 million decrease in net collateral activity with counterparties, primarily resulting from changes in the market prices of power and natural gas, changes in contracted commodity volumes, and decreases resulting from Ameren Illinois renewable energy contracts entered into pursuant to the FEJA.

A $19 million increase in interest payments, primarily due to an increase in the average outstanding debt at Ameren (parent) and Ameren Illinois.

A $17 million decrease, primarily resulting from increased coal inventory levels as less coal was purchased in 2019 due to delivery disruptions that occurred from flooding.

A $14 million increase in property tax payments atAmeren Missouri due to higher property tax values in 2019, compared with 2018. Property tax payments in a given year are based on the preceding years property tax values.

Refunds paid in 2020 of $1 3 million associated with the November 201 3 FERC complaint case, as discussed in Note 2 Rate and Regulatory Matters under Part I, Item 1, ofthis report.

The following items partially offset the decrease in Amerens cash from operating activities between periods:

A $28 million decrease in non-Callaway Energy Center maintenance costs at Ameren Missouri, primarily due to lower electric system infrastructure maintenance expenses as a result of decreased system load, disciplined cost management, the deferral of projects to future periods, and lower storm costs.

A $27 million decrease in payments for the employer portion of Social Security taxes as a result of a payment deferral allowed under the Coronavirus Aid, Relief, and Economic Security Act. Half of this deferral will be paid at the end of 2021 and the remaining half will be paid at the end of 2022.

A $22 million decrease in payments for nuclear refueling and maintenance outages at Ameren Missouris Callaway Energy Center, as the current year refueling and maintenance outage began in October 2020, while the prior year refueling and maintenance outage was completed in the second quarter of 2019.

Ameren Missouri Ameren Missouris cash provided by operating activities decreased $1 31 million in the first nine months of 2020, compared with the year-ago period. The following items contributed to the decrease:

A $147 million decrease resulting from decreased customer collections, primarily due to an increase in accounts receivable balances, a decrease in electric sales volumes, and a net decrease attributable to regulatory recovery mechanisms, partially offset by decreased fuel and purchased power costs.

A $32 million increase in payments to settle ARO liabilities, primarily related to CCR storage facilities.

A $23 million decrease, primarily resulting from increases to materials and supplies to support operations as levels were increased to mitigate against any potential supply disruptions.

A $17 million decrease, primarily resulting from increased coal inventory levels as less coal was purchased in 2019 due to delivery disruptions that occurred from flooding in 2019.

A net $16 million increase in collateral posted with counterparties, primarily resulting from changes in the market prices of power and natural gas and changes in contracted commodity volumes.

A $14 million increase in property tax payments due to higher property tax values in 2019, compared with 2018. Property tax payments in a given year are based on the preceding years property tax values.

A $14 million increase in pension and postretirement benefit plan contributions.

The following items partially offset the decrease in Ameren Missouris cash from operating activities between periods:

A $43 million decrease in income tax payments to Ameren (parent) pursuant to the tax allocation agreement, primarily due to the timing 62

of payments and lower taxable income in 2020.

A $28 million decrease in non-Callaway Energy Center maintenance costs, primarily due to lower electric system infrastructure maintenance expenses as a result of decreased system load, disciplined cost management, the deferral of projects to future periods, and lower storm costs.

A $22 million decrease in payments for nuclear refueling and maintenance outages at the Callaway Energy Center, as the current year refueling and maintenance outage began in October 2020, while the prior year refueling and maintenance outage was completed in the second quarter of 2019.

A $12 million decrease in payments for the employer portion of Social Security taxes as a result of a payment deferral allowed under the Coronavirus Aid, Relief, and Economic Security Act. Half of this deferral will be paid at the end of 2021 and the remaining half will be paid at the end of 2022.

Ameren Illinois Ameren Illinois cash provided by operating activities decreased $1 91 million in the first nine months of 2020, compared with the year-ago period. The following items contributed to the decrease:

A $136 million decrease resulting from decreased customer collections, primarily due to an increase in accounts receivable balances, which reflected an increase in amounts that were 30 days or greater past due or that were a part of a deferred payment arrangement, a decrease in sales volumes, and a net decrease attributable to regulatory recovery mechanisms, partially offset by decreased purchased power costs and volumes and natural gas costs.

A $32 million increase in income tax payments to Ameren (parent) pursuant to the tax allocation agreement, primarily due to the timing of payments in 2020.

A $17 million decrease, primarily resulting from increases to materials and supplies to support operations as levels were increased to mitigate against any potential supply disruptions.

An $1 I million increase in interest payments, primarily due to an increase in the average outstanding debt.

Refunds paid in 2020 of $9 million associated with the November 201 3 FERC complaint case, as discussed in Note 2 Rate and Regulatory Mailers under Part I, Item 1, of this report.

A net $9 million decrease in collateral received from counterparties, primarily resulting from changes in the market prices of power and natural gas, changes in contracted commodity volumes, and decreases resulting from renewable energy contracts entered into pursuant to the FEJA.

A $7 million increase in pension and postretirement benefit plan contributions.

The decrease in Ameren Illinois cash from operating activities between periods was partially offset by a $10 million decrease in payments for the employer portion of Social Security taxes as a result of a payment deferral allowed under the Coronavirus Aid, Relief, and Economic Security Act. Half of this deferral will be paid at the end of 2021 and the remaining half will be paid at the end of 2022.

Cash Flows from Investing Activities Amerens cash used in investing activities increased $1 83 million during the first nine months of 2020, compared with the year-ago period, primarily as a result of a $1 23 million increase in capital expenditures. Partially offsetting capital expenditure increases at Ameren Missouri and Ameren Illinois discussed below, ATXIs capital expenditures decreased $37 million, primarily as a result of decreased expenditures on the Mark Twain project as the project was placed in service in 201 9. Cash used in investing activities also increased $35 million due to the timing of nuclear fuel expenditures and $26 million due to net investment activity in the nuclear decommissioning trust fund at Ameren Missouri during the first nine months of 2020, compared with the year-ago period.

Ameren Missouris cash used in investing activities increased $92 million during the first nine months of 2020, compared with the year-ago period, primarily as a result of a $35 million increase due to the timing of nuclear fuel expenditures, a $27 million increase in capital expenditures, and a $26 million increase due to net investment activity in the nuclear decommissioning trust fund compared with the year-ago period. Ameren Missouris increase in capital expenditures was primarily related to electric delivery infrastructure upgrades and electric transmission system reliability projects.

Ameren Illinois cash used in investing activities increased $127 million during the first nine months of 2020, compared with the year-ago period, primarily due to a $131 million increase in capital expenditures primarily related to electric transmission system reliability projects.

Cash Flows from Financing Activities Cash provided by, or used in, financing activities is a result of our financing needs, which depend on the level of cash provided by operating activities, the level of cash used in investing activities, the level of dividends, and our long-term debt maturities, among other things. As a result of capital market volatility, due, in part, to the COVID-19 pandemic, and to increase net available liquidity, Ameren (parent) accelerated a debt issuance to April 2020, which had been planned for later in 2020, and used a portion of the proceeds to repay $350 million 63

of senior unsecured notes held by Ameren (patent) in October 2020.

Amerens cash provided by consolidated financing activities increased $466 million during the first nine months of 2020, compared with the year-ago period. During the first nine months of 2020, Ameren utilized proceeds from the issuance of $1 263 million of long-term debt for general corporate purposes, including to repay then-outstanding short-term debt, including short-term debt incurred in connection with the repayment at maturity of long-term debt of $85 million, and to fund, in part, investing activities. During the first nine months of 2020, Ameren repaid net short-term debt of $168 million. In comparison, during the first nine months of 201 9, Ameren utilized proceeds from the issuance of $900 million of long-term debt to repay then-outstanding short-term debt, including short-term debt incurred in connection with the repayment at maturity of long-term debt of

$329 million. During 2019, Ameren repaid net short-term debt of $53 million, and used cash provided by financing activities to fund, in part, investing activities. During the first nine months of 2020, Ameren paid common stock dividends of $367 million, compared with $350 million in dividend payments in the year-ago period.

Ameren Missouris financing activities provided cash of $1 39 million during the first nine months of 2020, compared to using cash of $49 million during the year-ago period. During the first nine months of 2020, Ameren Missouri utilized net proceeds from the issuance of $465 million of long-term debt to repay then-outstanding short-term debt, including short-term debt incurred in connection with the repayment at maturity of long-term debt of $85 million. During the first nine months of 2020, Ameren Missouri repaid net short-term debt of $234 million and used cash provided by financing activities to fund, in part, investing activities. In comparison, during the first nine months of 201 9, Ameren Missouri utilized net proceeds from the issuance of $450 million in long-term debt to repay then-outstanding short-term debt, including short-term debt incurred in connection with the repayment at maturity of long-term debt of $329 million, and net commercial paper issuances of $89 million to fund, in part, investing activities.

During the first nine months of 2020, Ameren Missouri did not pay common stock dividends, compared with $250 million in dividend payments in the year-ago period, due to an expected increase in investing cash needs, including the anticipated acquisition of wind generation facilities.

Ameren Illinois cash provided by financing activities increased $303 million during the first nine months of 2020, compared with the year-ago period. During the first nine months of 2020, Ameren Illinois received $350 million in capital contributions from Ameren (parent), and utilized net proceeds from commercial paper issuance of $1 89 million to fund, in part, investing activities. In comparison, during the first nine months of 2019, Ameren Illinois utilized net proceeds from commercial paper issuances of $237 million to fund, in part, investing activities.

See Long-term Debt and Equity in this section for additional information on maturities and issuances of long-term debt.

Credit Facility Borrowings and Liquidity The liquidity needs of the Ameren Companies are typically supported through the use of available cash, drawings under committed credit agreements, commercial paper issuances, and/or, in the case ofAmeren Missouri and Ameren Illinois, short-term affiliate borrowings. See Note 3 Short-term Debt and Liquidity under Part I, Item I

, of this report for additional information on credit agreements, commercial paper issuances, Amerens money pool arrangements and related borrowings, and relevant interest rates.

The following table presents Amerens consolidated liquidity as of September 30, 2020:

Ameren (parent) and Ameren Missouri:

Missouri Credit Agreement borrowing capacity 1200 Less: Ameren (parent) commercial paperoutstanding 19 Less: Ameren Missouri letters of credit 3

Missouri Credit Agreement subtotal 1, I 78 Ameren (parent) and Ameren Illinois:

Illinois Credit Agreement borrowing capacity 1, I 00 Less: Ameren (parent) commercial paper outstanding 11 Less: Ameren Illinois commercial paper outstanding 242 Less: Ameren Illinois letters of credit 2

Illinois Credit Agreement subtotal 845 Subtotal 2,023 Add: Cash and cash equivalents 6

Net Available Liquidity 2,029 The Credit Agreements, among other things, provide $2.3 billion of credit until maturity in December 2024. See Note 3 Short-term Debt and Liquidity under Part I, Item I, of this report for additional information on the Credit Agreements. During the nine months ended September 30, 2020, Ameren (parent), Ameren Missouri, and Ameren Illinois each borrowed under the Credit Agreements and issued commercial paper. Borrowings under the Credit Agreements and commercial paper issuances are based upon available interest rates at that time of the borrowing or issuance. As a result of volatility in the capital markets, the Ameren Companies borrowed under the Credit Agreements in certain instances in the first quarter of 2020 rather than issuing commercial paper.

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Ameren has a money pool agreement with and among its utility subsidiaries to coordinate and to provide for certain short-term cash and working capital requirements. As short-term capital needs arise, and based on availability of funding sources, Ameren Missouri and Ameren Illinois will access funds from the utility money pool, the Credit Agreements, or the commercial paper programs depending on which option has the lowest interest rates.

The issuance of short-term debt securities by Amerens utility subsidiaries is subject to FERC approval under the Federal Power Act. In March 2020, the FERC issued an order authorizing Ameren Missouri to issue up to $1 billion of short-term debt securities, which expires in March 2022. In September 2020, the FERC issued an order authorizing Ameren Illinois to issue up to $1 billion of short-term debt securities, which expires in September 2022. In July 2019, the FERC issued an order authorizing ATXI to issue up to $300 million of short-term debt securities, which expires in July 2021.

The Ameren Companies continually evaluate the adequacy and appropriateness of their liquidity arrangements for changing business conditions. When business conditions warrant, changes may be made to existing credit agreements or to other borrowing arrangements, or other arrangements may be made.

Long-term Debt and Equity The following table presents Amerens issuances (net of any issuance premiums or discounts) of long-term debt and equity, as well as redemptions and maturities of long-term debt for the nine months ended September 30, 2020 and 2019:

Month Issued, Redeemed, or Matured 2020 2019 Issuances of Long-term Debt Ameren:

3.50% Senior unsecured notes due 2031 April 798

2.50% Senior unsecured notes due 2024 September

450 Ameren Missouri:

2.95% First mortgage bonds due 2030 March 465

3.50% First mortgage bonds due 2029 March

450 Total Ameren long-term debt issuances I 263 900 Issuances of Common Stock Ameren:

DRPIus and 401(k)

Various 37 (a)(b) 54 (a)(b)

Total common stock issuances 37 54 Total Ameren long-term debt and common stock issuances I 300 954 Redemptions and Maturities of Long-term Debt Ameren Missouri:

5.00% Senior secured notes due 2020 February 85

6.70% Senior secured notes due 201 9 February

329 Ameren Illinois:

5.70% First mortgage bond due 2024 September

(c)

Total Ameren long-term debt redemptions and maturities 85 329 (a)

Ameren issued a total of 0.5 million and 0.7 million shares of common stock under its DRPlus and 401 (k) plan in the nine months ended September 30, 2020 and 2019, respectively.

(b)

Excludes 0.5 million and 0.8 million shares of common stock valued at $38 million and $54 million issued for no cash consideration in connection with stock-based compensation for the nine months ended September 30, 2020 and 2019, respectively.

(c)

Lessthan$1 million In October 2020, Ameren, Ameren Missouri, and Ameren Illinois filed a Form 5-3 shelf registration statement with the SEC, registering the issuance of an unspecified amount of certain types of securities. This registration statement became effective immediately upon filing and expires in October 2023.

See Note 4 Long-Term Debt and Equity Financings under Part I, Item 1, of this report for additional information, including proceeds from issuances of long-term debt, the use of those proceeds, Amerens forward equity sale agreement relating to 7.5 million shares of common stock, Ameren Missouris October 2020 issuance of $550 million in first mortgage bonds, Ameren (parent)s October 2020 redemption of $350 million of senior unsecured notes, and Ameren (parent)s capital contributions to Ameren Illinois.

Indebtedness Provisions and Other Covenants See Note 3 Short-term Debt and Liquidity under Part I, Item 1, of this report and Note 4 Short-term Debt and Liquidity and Note 5 Long-term Debt and Equity Financings under Part II, Item 8, ofthe Form 10-K for a discussion ofprovisions (and applicable cross-default 65

provisions) and covenants contained in our credit agreements, in ATXIs note purchase agreement, and in certain of the Ameren Companies indentures and articles of incorporation.

At September 30, 2020, the Ameren Companies were in compliance with the provisions and covenants contained in their credit agreements, indentures, and articles of incorporation, as applicable, and ATXI was in compliance with the provisions and covenants contained in its note purchase agreement.

We consider access to short-term and long-term capital markets to be a significant source of funding for capital requirements not satisfied by cash provided by our operating activities. Inability to raise capital on reasonable terms, particularly during times of uncertainty in the capital markets, could negatively affect our ability to maintain and expand our businesses. After assessing its current operating performance, liquidity, and credit ratings (see Credit Ratings below), Ameren, Ameren Missouri, and Ameren Illinois each believes that it will continue to have access to the capital markets on reasonable terms. However, events beyond Amerens, Ameren Missouris, and Ameren Illinois control may create uncertainty in the capital markets or make access to the capital markets uncertain or limited. Such events could increase our cost of capital and adversely affect our ability to access the capital markets.

Dividends The amount and timing of dividends payable on Amerens common stock are within the sole discretion of Amerens board of directors. Amerens board of directors has not set specific targets or payout parameters when declaring common stock dividends, but it considers various factors, including Amerens overall payout ratio, payout ratios of our peers, projected cash flow and potential future cash flow requirements, historical earnings and cash flow, projected earnings, impacts of regulatory orders or legislation, and other key business considerations. Ameren expects its dividend payout ratio to be between 55% and 70% of annual earnings over the next few years. On October 9, 2020, Amerens board of directors declared a quarterly common stock dividend of 51.5 cents per share payable on December 31

, 2020, to shareholders of record on December 9, 2020, resulting in an annualized equivalent dividend rate of $2.06 per share. The previous annualized equivalent dividend rate, based on the common stock dividend declared and paid in the third quarter of 2020, was $1.98 per share.

See Note 4 Short-term Debt and Liquidity and Note 5 Long-term Debt and Equity Financings under Part II, Item 8, of the Form 1 0-K for additional discussion of covenants and provisions contained in certain of the Ameren Companies financial agreements and articles of incorporation that would restrict the Ameren Companies payment of dividends in certain circumstances. At September 30, 2020, none of these circumstances existed at Ameren, Ameren Missouri, or Ameren Illinois and, as a result, these companies were not restricted from paying dividends.

The following table presents common stock dividends declared and paid by Ameren Corporation to its common shareholders and by Ameren subsidiaries to their parent, Ameren Corporation, for the nine months ended September 30, 2020 and 2019:

Nine Months 2020 2019 Ameren 367 350 Ameren Missouri

250 ATXI

15 Commitments For a listing of our obligations and commitments, see Other Obligations in Note 9 Commitments and Contingencies under Part I, Item I, of this report. See Note 1 1 Retirement Benefits under Part I, Item I, of this report for information regarding expected minimum funding levels for our pension plan.

Off-balance-sheet Arrangements At September 30, 2020, none of the Ameren Companies had any significant off-balance-sheet financing arrangements, other than the forward sale agreement relating to common stock and variable interest entities. See Note 1 Summary of Significant Accounting Policies under Part I, Item I, ofthis report for further detail concerning variable interest entities. See Note 5 Long-Term Debt and Equity under Part II, Item 8, of the Form I 0-K for further detail concerning the forward sale agreement relating to common stock.

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Credit Ratings Our credit ratings affect our liquidity, our access to the capital markets and credit markets, our cost of borrowing under our credit facilities and our commercial paper programs, and our collateral posting requirements under commodity contracts.

The following table presents the principal credit ratings by Moodys and S&P, as applicable, effective on the date of this report:

Moodys S&P Ameren:

Issuer/corporate credit rating Baal BBB+

Seniorunsecureddebt Baal BBB commercial paper P-2 A-2 Ameren Missouri:

Issuer/corporate credit rating Baal BBB+

Secured debt A2 A

Senior unsecured debt Baal Not Rated commercial paper P-2 A-2 Ameren Illinois:

Issuer/corporate credit rating A3 BBB+

Secured debt Al A

Senior unsecured debt A3 BBB+

commercial paper P-2 A-2 ATXI:

Issuer credit rating A2 Not Rated Senior unsecured debt A2 Not Rated A credit rating is not a recommendation to buy, sell, or hold securities. It should be evaluated independently of any other rating. Ratings are subject to revision or withdrawal at any time by the rating organization.

Collateral Postings Any weakening of our credit ratings may reduce access to capital and trigger additional collateral postings and prepayments. Such changes may also increase the cost of borrowing, resulting in an adverse effect on earnings. Cash collateral postings and prepayments made with external parties, including postings related to exchange-traded contracts, and cash collateral posted by external parties were immaterial at September 30, 2020. A sub-investment-grade issuer or senior unsecured debt rating (below Baa3 from Moodys or below EBB-from S&P) at September 30, 2020, could have resulted in Ameren, Ameren Missouri, or Ameren Illinois being required to post additional collateral or other assurances for certain trade obligations amounting to $167 million, $150 million, and $17 million, respectively.

Changes in commodity prices could trigger additional collateral postings and prepayments. Based on credit ratings at September 30, 2020, if market prices were I 5% higher or lower than September 30, 2020 levels in the next I 2 months and 20% higher or lower thereafter through the end of the term of the commodity contracts, then Ameren, Ameren Missouri, or Ameren Illinois could be required to post an immaterial amount, compared to each companys liquidity, of collateral or other assurances for certain trade obligations.

OUTLOOK Below are some key trends, events, and uncertainties that may reasonably affect our results of operations, financial condition, or liquidity, as well as our ability to achieve strategic and financial objectives, for 2020 and beyond. The continued effect ofthe COVID-19 pandemic on our results of operations, financial position, and liquidity in subsequent periods will depend on its severity and longevity, future regulatory or legislative actions with respect thereto, and the resulting impact on business, economic, and capital market conditions. We continue to assess the impacts the pandemic is having on our businesses, including but not limited to impacts on our liquidity; demand for residential, commercial, and industrial electric and natural gas services; more flexible payment plans for customers; the timing and extent to which recovery of incremental costs incurred, net of savings, and forgone customer late fee revenues at Ameren Missouri is allowed by the M0PSC; changes in our ability to disconnect customers for nonpayment; bad debt expense; supply chain operations; the availability of our employees and contractors; counterparty credit; capital construction; infrastructure operations and maintenance; energy-efficiency programs; and pension valuations. For additional information regarding recent rate orders, lawsuits, and pending requests filed with state and federal regulatory commissions, including those discussed below, see Note 2 Rate and Regulatory Matters under Part I, Item 1

, of this report and Note 2 Rate and Regulatory Matters under Part II, Item 8, of the Form 1 0-K.

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Operations In the first nine months of 2020, we have experienced a net decrease in our sales volumes, which have been, and continue to be, affected by the COVID-19 pandemic, among otherthings. Further, our customers paymentfor services has been adversely affected by the COVID-19 pandemic, which has led to an increase in our accounts receivable balances that are past due or that are a part of a deferred payment arrangement. Because of their regulatory frameworks, Ameren Illinois and ATXIs revenues are largely decoupled from changes in sales volumes. Additionally, Ameren Illinois electric distribution and natural gas distribution businesses have bad debt riders, which provide for recovery of bad debt write-offs, net of any subsequent recoveries. Pursuant to a June 2020 ICC order, Ameren Illinois electric bad debt rider provides for the recovery of bad debt expense in 2020. Ameren Missouri does not have a bad debt rider or regulatory tracking mechanism and its earnings are exposed to increases in bad debt expense. See the Results of Operations section above for additional information on our accounts receivable balances and changes in Ameren Missouris sales volumes in 2020, compared to 2019. Additionally, see Note 2 Rate and Regulatory Matters under Part I, Item 1, of this report for information on Ameren Missouris and Ameren Illinois reinstatement of customer disconnection and late fee charges for non-payment, requests filed with the MoPSC for accounting authority orders related to Ameren Missouris electric and natural gas services to allow Ameren Missouri to accumulate certain costs incurred, net of savings, and forgone customer late fee revenues related to the COVID-19 pandemic for consideration of recovery in future regulatory rate reviews, and a June 2020 ICC order in a service disconnection moratorium proceeding, which required Ameren Illinois to implement more flexible credit and collection practices and allowed for recovery of costs incurred related to the COVID-19 pandemic and forgone late fees.

The PISA permits Ameren Missouri to defer and recover 85% of the depreciation expense and a return at the applicable WACC on investments in certain property, plant, and equipment placed in service after September 1, 201 8, and not included in base rates. The regulatory asset for accumulated PISA deferrals also earns a return at the applicable WACC, with all approved PISA deferrals added to rate base prospectively and recovered over a period of 20 years following a regulatory rate review. Additionally, under the RESRAM, Ameren Missouri is permitted to recover the 1 5% of depreciation expense and a return at the applicable WACC for investments in renewable generation plant placed in service and not recovered under the PISA. Accumulated RESRAM deferrals earn carrying costs at short-term interest rates. The PISA and the RESRAM mitigate the effects of regulatory lag between regulatory rate reviews. Those investments not eligible for recovery under the PISA and the remaining 15% of certain property, plant, and equipment placed in service, unless eligible for recovery under the RESRAM, remain subject to regulatory lag. Ameren Missouri recognizes the cost of debt on PISA deferrals in revenue, instead of using the applicable WACC, with the difference recognized in revenues when recovery of such deferrals is reflected in customer rates. As a result of the PISA election, additional provisions of the law apply to Ameren Missouri, including limitations on electric customer rate increases. Both the rate increase limitation and the PISA are effective through December 2023, unless Ameren Missouri requests and the MoPSC approves an extension through December 2028.

In 201 8, the MoPSC issued an order approving Ameren Missouris MEEIA 201 9 plan. The initial plan included a portfolio of customer energy-efficiency programs through December 2021 and low-income customer energy-efficiency programs through December 2024, along with a rate-adjustment mechanism. Ameren Missouri intends to invest $226 million over the life of the plan, including $65 million per year through 2021 and

$70 million in 2022. The plan includes the continued use ofthe MEEIA rider, which allows Ameren Missouri to collect from, or refund to, customers any difference in actual MEEIA program costs and related lost electric margins and the amounts collected from customers. In addition, the plan includes a performance incentive that provides Ameren Missouri an opportunity to earn additional revenues by achieving certain customer energy-efficiency goals. In August 2020, the MoPSC issued an order approving a unanimous stipulation and agreement establishing performance incentives for the 2022 program year. The order also approved Ameren Missouris energy savings results for the first year of the MEEIA 201 9 program. As a result of this order and in accordance with revenue recognition guidance, Ameren Missouri recognized revenues of $6 million in the third quarter of 2020. If the target goals are achieved for 2020, 2021, and 2022, additional revenues of $1 0 million,

$13 million, and $11 million would be recognized in 2021, 2022, and 2022, respectively. Incremental additional revenues of$3 million, $3 million, and $1 million may be earned for 2020, 2021

, and 2022, respectively, and would be recognized in the respective following year if Ameren Missouri exceeds its targeted energy savings goals. Ameren Missouris ability to achieve and/or exceed targeted energy savings goals could be affected by the COVID-19 pandemic. Ameren Missouri recognized $28 million, $11 million, and $37 million in revenues related to MEEIA performance incentives in 2016, 2018, and 2019, respectively.

In March 2020, the MoPSC issued an order in Ameren Missouris July 2019 electric service regulatory rate review, resulting in a decrease of

$32 million to Ameren Missouris annual revenue requirement for electric retail service. The order reduced the annualized base level of net energy costs pursuant to the FAC by approximately $1 I 5 million from the base level established in the MoPSCs March 201 7 electric rate order.

The order also changed the annualized regulatory asset and liability amortization amounts and the base level of expenses for regulatory tracking mechanisms. On an annualized basis, these changes reflect approximately $20 million of increased revenues and approximate decreases in purchased power expenses of $1 5 million, other operating and maintenance expenses of $60 million, and income tax expenses of

$20 million. Additionally, the annual revenue requirement incorporated increases of approximately $50 million for the reduction in sales volumes resulting from MEEIA programs and approximately $50 million of depreciation and amortization expense for amounts previously deferred under PISA. The increase in the annual revenue requirement related to the 68

MEEIA programs is seasonally weighted to the summer. One of the stipulation and agreements approved by the M0PSCs March 2020 order states that the net impact of the revenue and expense changes noted above reflects a 9.4% to 9.8% ROE on an unspecified percent of common equity applicable to rate base. The new rates, base level of expenses, and amortizations became effective on April 1

, 2020.

Ameren Missouri expects to file for electric and natural gas service regulatory rate reviews in the first half of 2021

. Ameren Missouri expects key drivers of the electric service regulatory rate review to include increased infrastructure investments and other costs of service. Electric base rates were last reset on April 1

, 2020, and are required to be reset at least every four years to allow for continued use of the FAC. Natural gas base rates were last reset on September 1

, 2019.

Ameren Illinois and ATXI use a forward-looking rate calculation with an annual revenue requirement reconciliation for each companys electric transmission business. Based on expected rate base growth and the currently allowed 10.52% ROE, the revenue requirements included in 2020 rates for Ameren Illinois and ATXIs electric transmission businesses are $31 3 million and $1 92 million, respectively. These revenue requirements represent an increase in Ameren Illinois and ATXIs revenue requirements of $16 million and $15 million, respectively, from the revenue requirements reflected in 2019 rates, primarily due to expected rate base growth. These rates will affect Ameren Illinois and ATXIs cash receipts during 2020, but will not determine their respective electric transmission service operating revenues, which will instead be based on 2020 actual recoverable costs, rate base, and a return on rate base at the applicable WACC as calculated under the FERC formula ratemaking framework.

There are various legal proceedings pending that could result in a change to the allowed base ROE for FERC-regulated transmission rate base under the MISO tariff. A 50 basis point change in the FERC-allowed base ROE would affect Amerens and Ameren Illinois annual net income by an estimated $10 million and $6 million, respectively, based on each companys 2020 projected rate base.

Ameren Illinois electric distribution service performance-based formula ratemaking framework allows Ameren Illinois to reconcile electric distribution service rates to its actual revenue requirement on an annual basis. If a given years revenue requirement varies from the amount collected from customers, an adjustment is made to electric operating revenues with an offset to a regulatory asset or liability to reflect that years actual revenue requirement, independent of actual sales volumes. The regulatory balance is then collected from, or refunded to, customers within two years from the end of the year. Unless extended, the formula ratemaking framework expires at the end of 2022. If not extended, Ameren Illinois would then be required to establish future rates through a traditional regulatory rate review, which would allow the use of a future test year, with the ICC. The decoupling provisions extend beyond the end of the formula ratemaking by law, which ensures that Ameren Illinois electric distribution revenues authorized in a regulatory rate review are not affected by changes in sales volumes.

In 2019, the ICC issued an order in Ameren Illinois annual update filing that approved a $7 million decrease in Ameren Illinois electric distribution service rates beginning in January 2020. Illinois law provides for an annual reconciliation of the electric distribution revenue requirement as is necessary to reflect the actual costs incurred and a return at the applicable WACC on year-end rate base in a given year with the revenue requirement that was reflected in customer rates for that year. Consequently, Ameren Illinois 2020 electric distribution service revenues will be based on its 2020 actual recoverable costs, 2020 year-end rate base, and a return at the applicable WACC as calculated under the Illinois performance-based formula ratemaking framework. As of September 30, 2020, Ameren Illinois expects its 2020 year-end rate base to be $3.4 billion. The 2020 revenue requirement reconciliation will be collected from, or refunded to, customers in 2022. A 50 basis point change in the annual average of the monthly yields ofthe 30-year United States Treasury bonds would result in an estimated $9 million change in Amerens and Ameren Illinois annual net income, based on Ameren Illinois 2020 projected year-end rate base. Ameren Illinois allowed ROE for the first nine months of 2020 and 2019 was based on an expected annual average of the monthly yields ofthe 30-year United States Treasury bonds of 1.5% and 2.5%, respectively.

In April 2020, Ameren Illinois filed its annual electric distribution service formula rate update with the ICC, requesting a reduction of $45 million in its rates. An ICC decision in this proceeding is expected by December 2020, with new rates effective January 2021

. These rates will affect Ameren Illinois cash receipts during 2021

, but will not affect electric distribution service revenues, which will be based on 2021 actual recoverable costs, 2021 year-end rate base, and a return at the applicable WACC as calculated under the Illinois performance-based formula ratemaking framework.

In September 2020, Ameren Illinois filed a revised request seeking to increase its annual revenues for natural gas delivery service by $97 million, which includes an estimated $46 million of annual revenues that would otherwise be recovered under the QIP and other riders. A decision by the ICC in this proceeding is required by January 2021

, with new rates expected to be effective in February 2021

. Ameren Illinois cannot predict the level of any delivery service rate change the ICC may approve, nor whether any rate change that may eventually be approved will be sufficient to enable Ameren Illinois to earn a reasonable return on investments when the rate changes go into effect.

Ameren Illinois earns a return at the applicable WACC on its electric energy-efficiency program investments. Ameren Illinois electric energy-efficiency investments are deferred as a regulatory asset and earn a return at the applicable WACC, with the ROE based on the 69

annual average of the monthly yields of the 30-year United States Treasury bonds plus 580 basis points. The allowed ROE on electric energy-efficiency investments can be increased or decreased by up to 200 basis points, depending on the achievement of annual energy savings goals.

Pursuantto the FEJA, Ameren Illinois plans to invest up to approximately $100 million per year in electric energy-efficiency programs through 2024, and will earn a return on those investments. While the ICC has approved a plan consistent with this spending level through 2021 the ICC has the ability to reduce the amount of electric energy-efficiency savings goals in future plan program years if there are insufficient cost-effective programs available, which could reduce the investments in electric energy-efficiency programs. The electric energy-efficiency program investments and the return on those investments are collected from customers through a rider and are not included in the electric distribution service performance-based formula ratemaking framework.

In February 2020, the MoPSC issued an order approving a stipulation and agreement allowing Ameren Missouri to defer and amortize maintenance expenses related to scheduled refueling and maintenance outages at its Callaway Energy Center. Maintenance expenses associated with the fall 2020 refueling and maintenance outage are being deferred, as incurred, as a regulatory asset, and will be amortized after completion of the outage. Maintenance expenses will be amortized over the period between refueling and maintenance outages, which is approximately 1 8 months. Ameren Missouris scheduled fall 2020 outage began in early October 2020. Ameren Missouri expects to incur approximately $40 million in maintenance expenses related to this outage. During a scheduled outage, depending on the availability of its other generation sources and the market prices for power, Ameren Missouris purchased power costs may increase and the amount of excess power available for sale may decrease versus non-outage years. Changes in purchased power costs and excess power available for sale are included in the FAC, which results in limited impacts to earnings. Prior to 2020, maintenance expenses for refueling and maintenance outages were expensed as incurred.

Ameren Missouri and Ameren Illinois continue to make infrastructure investments and expect to seek increases to electric and natural gas rates to recover the cost of investments and earn an adequate return. Ameren Missouri and Ameren Illinois will also seek new, or to maintain existing, legislative solutions to address regulatory lag and to support investment in their utility infrastructure for the benefit of their customers. Ameren Missouri and Ameren Illinois continue to face cost recovery pressures, including limited economic growth in their service territories, economic impacts of COVID-19, customer conservation efforts, the impacts of additional customer energy-efficiency programs, and increased customer use of increasingly cost-effective technological advances, including private generation and energy storage. However, over the long-term, we expect the decreased demand to be partially offset by increased demand resulting from increased electrification of the economy for efficiencies and as a means to address economy-wide C02 emission concerns. Increased investments, including expected future investments for environmental compliance, system reliability improvements, and potential new generation sources, result in rate base and revenue growth but also higher depreciation and financing costs.

Liquidity and Capital Resources Our customers payment for our services has been adversely affected by the COVID-19 pandemic, resulting in a decrease to our cash flow from operations. See the Results of Operations section above for additional information on our accounts receivable balances. Further, our liquidity and our capital expenditure plans could be adversely affected by other impacts resulting from the COVID-19 pandemic, including but not limited to potential impacts on our ability to access the capital markets on reasonable terms and when needed, Ameren Missouris expected wind generation acquisitions, and the timing of tax payments and the utilization of tax credits. We expect to make significant capital expenditures to improve our electric and natural gas utility infrastructure, however, disruptions to the capital markets and the ability of our suppliers and contractors to perform as required under their contracts could impact the execution of our capital investment strategy. For further discussion on the impacts to our ability to access the capital markets and Ameren Missouris expected wind generation acquisitions, see below.

In February 2020, Ameren Missouri filed an update to its Smart Energy Plan with the MoPSC, which includes a five-year capital investment overview with a detailed one-year plan for 2020. The plan is designed to upgrade Ameren Missouris electric infrastructure and includes investments that will upgrade the grid and accommodate more renewable energy. Investments under the plan are expected to total approximately $7.6 billion over the five-year period from 2020 through 2024, with expenditures largely eligible for recovery under the PISA and the RESRAM. These investments exclude incremental renewable generation investment opportunities of 950 megawatts by 2024, which are included in Ameren Missouris 2020 IRP discussed below. The planned investments beyond 2023 included in the five-year range above are based on the assumption that Ameren Missouri requests and receives MoPSC approval of an extension of the PISA. As a part of its Smart Energy Plan, Ameren Missouri expects to build solar generation facilities, including utility scale facilities and nonresidential customer site facilities. In September 201 9, Ameren Missouri filed for certificates of convenience and necessity with the MoPSC to build three solar-plus-storage facilities. In June 2020, Ameren Missouri withdrew its application for the certificates of convenience and necessity following intervenor feedback. Ameren Missouri is evaluating new solar generation facilities as a part of its integrated resource plan, which was filed in September 2020. Also in 201 9, the MoPSC approved Ameren Missouris Charge Ahead program, which provides incentives for the development of over 1,000 electric vehicle charging stations along highways and at various locations in communities throughout Ameren Missouris service territory.

The purpose of the program is to promote the development of electric vehicle charging infrastructure that will enable long-distance electric vehicle travel and encourage electrification of the transportation sector.

70

In September 2020, Ameren Missouri filed its 2020 IRP with the MoPSC, which targets cleaner and more diverse sources of energy generation, including solar, wind, hydro, and nuclear power, and supports increased investment in new energy technologies. The plan, which is subject to review by the MoPSC, also includes expanding renewable sources by adding 3,100 megawatts of renewable generation by the end of 2030 and a total of 5,400 megawatts of renewable generation by 2040. These amounts include the 700 megawatts of wind generation projects discussed below, which are expected to be substantially complete in 2020 and fully in-service in early 2021, and will support Ameren Missouris compliance with the state of Missouris requirement of achieving 1 5% of native load sales from renewable energy sources by 2021

, subject to customer rate increase limitations. Based on current and projected market prices for energy and for wind and solar generation technologies, among other factors, Ameren Missouri expects its ownership of these renewable resources would represent the lowest-cost option for customers. The plan also includes advancing the retirement dates of the Sioux and Rush Island coal-fired energy centers to 2028 and 2039, respectively, which are subject to the approval of a change in the assets depreciable lives by the MoPSC in a future regulatory rate review, the continued implementation of customer energy-efficiency programs, and the expectation that Ameren Missouri will seek an extension of the operating license for the Callaway Energy Center beyond its current 2044 expiration date. Ameren Missouris plan could be affected by, among other factors: Ameren Missouris ability to obtain a certificate of convenience and necessity from the MoPSC, and any other required approvals for the addition of renewable resources, retirement of energy centers, and new or continued customer energy-efficiency programs; the ability of developers to meet contractual commitments and timely complete projects, which is dependent upon the availability of necessary materials and equipment, including those that are affected by the disruptions in the global supply chain caused by the COVID-19 pandemic, among other things; the availability of federal production and investment tax credits related to renewable energy and Ameren Missouris ability to use such credits; the cost ofwind, solar, and other renewable generation and storage technologies; changes in environmental laws or requirements, including those related to carbon emissions; energy prices and demand; and Ameren Missouris ability to obtain timely interconnection agreements with the MISO or other RTOs at an acceptable cost.

In connection with the 2020 IRP filing discussed above, Ameren established a goal of achieving net-zero carbon emissions by 2050. Ameren is also targeting a 50% C02 emission reduction by 2030 and an 85% reduction by 2040 from the 2005 level. In order to meet these goals, among other things, the 2020 IRP includes retiring Ameren Missouris Meramec and Labadie coal-fired energy centers at the end of their useful lives and advancing the retirement dates of its Sioux and Rush Island coal-fired energy centers. As indicated in the 2020 IRP, the Meramec, Sioux, Rush Island, and Labadie energy centers are expected to be retired by 2022, 2028, 2039, and 2042, respectively. The next integrated resource plan is expected to be filed in September 2023.

Consistent with its 2020 IRP filing, Ameren Missouri entered into build-transfer agreements to acquire, after construction, an up-to 300-megawatt wind generation facility and an up-to 400-megawatt wind generation facility in 201 9 and 201 8, respectively. Delays to the original construction schedule have occurred in 2020 due to changes in supply and construction activities. During the third quarter of 2020, all remaining wind turbine deliveries for the up-to 400-megawatt project were completed. Based on the construction schedule, Ameren Missouri expects this project to be placed in-service by the end of 2020. At this time, due to manufacturing, shipping, and other supply chain issues in 2020, and, based on an updated construction schedule from the developer, Ameren Missouri expects the up-to 300-megawatt project to be partially placed in-service by the end of 2020, and the remaining portion ofthe project, representing approximately $200 million of investment, to be placed in-service in the first quarter of 2021

. Ameren Missouri and the developer of the up-to 300-megawatt project continue to monitor the impact to this projects schedule.

Through 2024, we expect to make significant capital expenditures to improve our electric and natural gas utility infrastructure, with a major portion directed to our transmission and distribution systems. We estimate that we will invest up to $16.6 billion (Ameren Missouri up to $8.4 billion; Ameren Illinois up to $8.0 billion; ATXI up to $0.2 billion) of capital expenditures during the period from 2020 through 2024. Amerens and Ameren Missouris estimates include the 700 megawatts of wind generation projects discussed above, but exclude incremental renewable generation investment opportunities of 950 megawatts by 2024, which are included in Ameren Missouris 2020 IRP.

Environmental regulations, including those related to C02 emissions, or other actions taken by the EPA, could result in significant increases in capital expenditures and operating costs. Certain of these regulations are being challenged through litigation, or reviewed or recommended for repeal by the EPA, or new replacement or alternative regulations are being contemplated, proposed, or adopted by the EPA and state regulators. The ultimate implementation of any of these regulations, as well as the timing of any such implementation, is uncertain. However, the individual or combined effects of existing and new environmental regulations could result in significant capital expenditures, increased operating costs, or the closure or alteration of some of Ameren Missouris coal-fired energy centers. Ameren Missouris capital expenditures are subject to MoPSC prudence reviews, which could result in cost disallowances as well as regulatory lag. The cost ofAmeren Illinois purchased power and natural gas purchased for resale could increase. However, Ameren Illinois expects that these costs would be recovered from customers with no material adverse effect on its results of operations, financial position, or liquidity. Amerens and Ameren Missouris earnings could benefit from increased investment to comply with environmental regulations if those investments are reflected and recovered on a timely basis in customer rates.

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Our results of operations, financial position, and liquidity have been and are expected to continue to be adversely affected by the international public health emergency associated with the COVID-19 pandemic.

The COVID-1 9 pandemic continues to be a rapidly evolving situation. In the first nine months of 2020, we experienced a net decrease in our sales volumes, an increase in our accounts receivable balances that were past due or that were a part of a deferred payment arrangement, and a decline in our cash collections from customers. The continued effect ofthe COVID-19 pandemic on our results ofoperations, financial position, and liquidity in subsequent periods will depend on its severity and longevity, future regulatory or legislative actions with respect thereto, and the resulting impact on business, economic, and capital market conditions. It may also affect Ameren Missouris ability to recover any lost revenues or incremental costs. As a result of the COVID-1 9 pandemic, measures have been taken by local, state, and federal governments, such as travel bans, quarantines, and shelter-in place orders. Shelter-in-place orders began taking effect in our service territories in mid-March 2020. These orders generally required individuals to remain at home and precluded or limited the operation of businesses that were deemed nonessential. In mid-May 2020, shelter-in-place orders effective in our service territories began to be relaxed, with individuals allowed to leave their homes and nonessential businesses allowed to begin reopening. However, certain restrictions remain in place that limit individual activities and the operation of nonessential businesses. Additional restrictions may be imposed in the future. Amerens business operations are deemed essential and are not directly impacted by the shelter-in-place orders. As a result ofthe COVID-19 pandemic, economic activity has been disrupted in the service territories of Ameren Missouri and Ameren Illinois. It has also caused disruptions in the capital markets, which could adversely affect our ability to access these markets on reasonable terms and when needed. These disruptions could continue for a prolonged period of time or become more severe.

We rely on the issuance of short-term and long-term debt and equity as significant sources of liquidity and funding for capital requirements not satisfied by our operating cash flow, as well as to refinance existing long-term debt. Disruptions to the capital markets as a result of the COVID-1 9 pandemic could negatively affect our ability to maintain and to expand our businesses. In addition, our credit ratings may be impacted by the economic conditions ofthe COVID-19 pandemic. The COVID-19 pandemic could lead to events beyond our control, such as further depressed economic conditions or extreme volatility in the debt, equity, or credit markets, and might create uncertainty that could increase our cost of capital or impair or eliminate our ability to access the debt, equity, or credit markets, including our ability to draw on bank credit facilities or issue commercial paper.

As a result ofthe COVID-19 pandemic, we have experienced and expectto continue to experience changes to our sales volumes. In the three and nine months ended September 30, 2020, compared to the same periods in 2019, Ameren Missouri experienced a reduction in commercial and industrial electric sales volumes, partially offset by increased electric sales volumes to higher margin residential customers, excluding the estimated effects of weather and customer energy-efficiency programs. While the impacts of the COVID-1 9 pandemic are difficult to predict, Ameren Missouri expects the net reduction in sales volumes, excluding the estimated effects of weather and customer energy-efficiency programs, to continue in the fourth quarter of 2020, compared to the same period in 201 9. The COVID-19 pandemic may continue to affect Ameren Missouris total electric sales volumes and sales volumes by customer class beyond 2020. Assuming a ratable change in Ameren Missouris electric sales volumes by month, a I % change for the calendar year 2020 to residential, commercial, and industrial customers would affect earnings per diluted share by approximately 3 cents, 2 cents, and a half-cent, respectively. The actual change in earnings per diluted share will be affected by the timing of sales volume changes due to seasonal customer rates. Pursuant to the PISA, Ameren Missouris electric rates are limited to a 2.85% compound annual growth rate cap. Continued long-term declines in sales volumes, along with increased capital investments and operating costs, could result in Ameren Missouris inability to recover amounts exceeding the rate cap. Ameren Illinois also experienced decreases in electric and natural gas sales volumes in the three and nine months ended September 30, 2020. While the revenues from Ameren Illinois electric distribution business, residential and small nonresidential customers of Ameren Illinois natural gas distribution business, and Ameren Illinois and ATXIs electric transmission businesses are decoupled from changes in sales volumes, earnings at Ameren Missouri and those associated with Ameren Illinois large nonresidential natural gas customers are exposed to such changes.

Our customers payment for our services has been adversely affected by the COVID-19 pandemic, resulting in a decrease to our cash flow from operations. Ameren Missouri suspended disconnections for customer nonpayment and charging late fees in mid-March 2020, and resumed those activities for commercial and industrial customers in mid-July 2020 and residential customers in early August 2020. Ameren Illinois resumed disconnection activities for commercial and industrial customers for nonpayment in early August 2020 and residential customers in mid-September 2020, with the exception of residential customers classified as low income, expressing a financial hardship, or relying on medical equipment.

Disconnections for nonpayment for these residential customers are expected to begin in April 2021

, which is after the annual winter moratorium period on disconnections from December 1

, 2020 to March 31

, 2021

. Ameren Illinois also resumed charging late fees to all customers in late July 2020, following the suspension of both disconnections and late fees for all customers in mid-March 2020. However, future regulatory or legislative action could require suspension of customer disconnections and/or late fees, among other things, for an extended period of time. As of September 30, 2020, accounts receivable balances that were 30 days or greater past due or that were a part of a deferred payment arrangement represented 26%, 18%, and 35%, or $151 million, $49 million, and $102 million, ofAmerens, Ameren Missouris, and Ameren Illinois customer trade receivables before allowance for doubtful accounts, respectively. As of September 30, 2019, these percentages were 13%, 9%, and 18%, or

$65 million, $23 million, and $42 million, for Ameren, Ameren Missouri, and Ameren Illinois, respectively. Ameren Illinois electric distribution and natural gas distribution businesses have bad debt riders, which 74

provide for recovery of bad debt write-offs, net of any subsequent recoveries. Pursuant to a June 2020 ICC order, Ameren Illinois electric bad debt rider provides for the recovery of bad debt expense in 2020. Ameren Missouri does not have a bad debt rider or regulatory tracking mechanism and its earnings are exposed to increases in bad debt expense. While Ameren Missouri will be seeking recovery of certain COVID-19 pandemic related costs incurred, net of savings, and forgone customer late revenues, it could be unsuccessful in obtaining regulatory approval to recover them, which may adversely affect Ameren and Ameren Missouris results of operations.

In addition, suppliers and contractors may not perform as provided under their contracts. This could cause delays in construction projects, including additional delays related to Ameren Missouris expected acquisition of two wind generation facilities, or the performance of necessary maintenance to our electric and natural gas infrastructure, which could lead to failures of equipment that can result in unanticipated liabilities or unplanned outages. Delays in our construction projects could also result in reduced planned capital expenditures and decreased rate base growth.

Also, our businesses depend on skilled professional and technical employees. Our operations could be adversely affected if a large portion of our employees contracted COVID-19 or became quarantined atthe same time. This could lead to facility shutdowns and disruptions in the delivery of electricity and natural gas to our customers. In addition, remote working arrangements increase our data security risks, including loss of data related to sensitive customer, employee, financial, and operating system information, through insider or outsider actions.

Ameren cannot predictthe extent or duration ofthe COVID-19 pandemic or its effects on the global, national, or local economy, the capital markets, or its customers, suppliers, business continuity plans, results of operations, financial position, liquidity, planned rate base growth, or sales volumes.

ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS.

Ameren Corporation, Ameren Missouri, and Ameren Illinois did not purchase equity securities reportable under Item 703 of Regulation S-K during the period from July 1

, 2020, to September 30, 2020.

75

ITEM 6. EXHIBITS.

The documents listed below are being filed or have previously been filed on behalf of the Ameren Companies and are incorporated herein by reference from the documents indicated and made a part hereof. Exhibits not identified as previously filed are filed herewith.

Exhibit Designation Registrant(s)

Nature of Exhibit Previously Filed as Exhibit to:

Instruments Defining Rights of Security Holders, Including Indentures 4.1 Ameren SupIementaI Indenture to the Ameren Missouri Mortgage, dated October 9, 2020 Form 8-K, Exhibit 4.2, Ameren Missouri October 1

. 2020, for 2.625% First MortqaQe Bonds due 2051 File No. 1-2967 Rule 13a-14(a) I 15d-14(a) Certifications 31.1 Ameren Rule 13a-14(a)/15d-14(a) Certification of Princioal Executive Officer of Ameren 31.2 Ameren Rule 13a-14(a)/15d-14(a) Certification of Principal Financial Officer of Ameren 31.3 Ameren Missouri Rule 13a-14(a)/15d-14(a) Certification of Principal Executive Officer of Ameren Missouri 31.4 Ameren Missouri Rule 1 3a-14(a)/1 5d-1 4(a) Certification of Principal Financial Officer of Ameren Missouri 31.5 Ameren Illinois Rule 13a-14(a)/15d-14(a) Certification of Principal Executive Officer of Ameren Illinois 31.6 Ameren Illinois Rule 13a-14(a)/15d-14(a) Certification ofPrincipal Financial Officer of Ameren Illinois Section 1350 Certifications

32. 1 Ameren Section 1 350 Certification of Principal Executive Officer and Principal Financial Officer of Ameren 32.2 Ameren Missouri Section 1350 Certification of Principal Executive Officer and Principal Financial Officer of Ameren Missouri 32.3 Ameren Illinois Section 1350 Certification of Principal Executive Officer and Principal Financial Officer ofAmeren Illinois Interactive Data Files 101 INS Ameren Companies Inline XBRL Instance Document

- the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document 1 01.SCH Ameren Companies Inline XBRL Taxonomy Extension Schema Document 1 01 CAL Ameren Companies Inline XBRL Taxonomy Extension Calculation Linkbase Document 1O1.LAB Ameren Companies Inline XBRL Taxonomy Extension Label Linkbase Document 1O1.PRE Ameren Companies Inline XBRL Taxonomy Extension Presentation Linkbase Document 1O1.DEF Ameren Companies Inline XBRL Taxonomy Extension Definition Document 104 Ameren Companies Cover Page Interactive Data File (formatted as Inline XBRL and contained in Exhibit 101)

The file number references for the Ameren Companies filings with the SEC are: Ameren, 1-14756; Ameren Missouri, 1-2967; and Ameren Illinois, 1-3672.

Each registrant hereby undertakes to furnish to the SEC upon request a copy of any long-term debt instrument not listed above that such registrant has not filed as an exhibit pursuant to the exemption provided by Item 601(b)(4)(iii)(A) of Regulation S-K.

76

SIGNATURES Pursuant to the requirements of the Exchange Act, each registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. The signature for each undersigned company shall be deemed to relate only to matters having reference to such company or its subsidiaries.

AMEREN CORPORATION (Registrant)

/5/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)

UNION ELECTRIC COMPANY (Registrant)

/5/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)

AMEREN ILLINOIS COMPANY (Registrant)

/5/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)

Date: November 5, 2020 77

Exhibit 31.1 RULE I 3a-1 4(a)/i 5U-i 4(a) CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER OF AMEREN CORPORATION (required by Section 302 of the Sarbanes-Oxtey Act of 2002)

I, Warner L. Baxter, certify that:

I I have reviewed this report on Form iO-Q for the quarterly period ended September 30, 2020 of Ameren Corporation; 2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report; 3.

Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report; 4.

The registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules i3a-i5(e) and 15d-i5(e)) and internal control over financial reporting (as defined in Exchange Act Rules i3a-i5(f) and i5d-1 5(f)) for the registrant and have:

a)

Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared; b)

Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles; c)

Evaluated the effectiveness of the registrants disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and d)

Disclosed in this report any change in the registrants internal control over financial reporting that occurred during the registrants most recent fiscal quarter (the registrants fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrants internal control over financial reporting; and 5.

The registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrants auditors and the audit committee of the registrants board of directors (or persons performing the equivalent functions):

a)

All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrants ability to record, process, summarize and report financial information; and b)

Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrants internal control over financial reporting.

Date: November 5, 2020

/5/ Warner L. Baxter Warner L. Baxter Chairman, President and Chief Executive Officer (Principal Executive Officer)

Exhibit 31.2 RULE 1 3a-1 4(a)/i 5d-1 4(a) CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER OF AMEREN CORPORATION (requited by Section 302 of the Sarbanes-Oxley Act of 2002)

I, Michael L. Moehn, certify that:

1 I have reviewed this report on Form 1 0-Q for the quarterly period ended September 30, 2020 of Ameren Corporation; 2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report; 3.

Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report; 4.

The registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-1 5(e) and 15d-1 5(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-1 5(f) and 1 5d-15(f)) for the registrant and have:

a)

Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared; b)

Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles; c)

Evaluated the effectiveness of the registrants disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and d)

Disclosed in this report any change in the registrants internal control over financial reporting that occurred during the registrants most recent fiscal quarter (the registrants fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrants internal control over financial reporting; and 5.

The registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrants auditors and the audit committee of the registrants board of directors (or persons performing the equivalent functions):

a)

All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrants ability to record, process, summarize and report financial information; and b)

Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrants internal control over financial reporting.

Date: November 5, 2020 Is/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)

Exhibit 31.3 RULE 1 3a-1 4(a)/i 5d-i 4(a) CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER OF UNION ELECTRIC COMPANY (required by Section 302 of the Sarbanes-Oxley Act of 2002)

I, Martin J. Lyons, Jr., certify that:

i I have reviewed this report on Form i 0-Q for the quarterly period ended September 30, 2020 of Union Electric Company; 2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report; 3.

Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report; 4.

The registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules i3a-i5(e) and i5d-i5(e)) and internal control over financial reporting (as defined in Exchange Act Rules i3a-i5(f) and i5d-i 5(f)) for the registrant and have:

a)

Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared; b)

Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles; c)

Evaluated the effectiveness of the registrants disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and d)

Disclosed in this report any change in the registrants internal control over financial reporting that occurred during the registrants most recent fiscal quarter (the registrants fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrants internal control over financial reporting; and 5.

The registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrants auditors and the audit committee of the registrants board of directors (or persons performing the equivalent functions):

a)

All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrants ability to record, process, summarize and report financial information; and b)

Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrants internal control over financial reporting.

Date: November 5, 2020

/5/ Martin J. Lyons, Jr.

Martin J. Lyons, Jr.

Chairman and President (Principal Executive Officer)

Exhibit 31.4 RULE 13a-14(a)/15d-14(a) CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER OF UNION ELECTRIC COMPANY (required by Section 302 of the Sarbanes-Oxley Act of 2002)

I, Michael L. Moehn, certify that:

I I have reviewed this report on Form 1 0-Q for the quarterly period ended September 30, 2020 of Union Electric Company; 2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report; 3.

Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report; 4.

The registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a)

Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared; b)

Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles; c)

Evaluated the effectiveness of the registrants disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and d)

Disclosed in this report any change in the registrants internal control over financial reporting that occurred during the registrants most recent fiscal quarter (the registrants fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrants internal control over financial reporting; and 5.

The registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrants auditors and the audit committee of the registrants board of directors (or persons performing the equivalent functions):

a)

All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrants ability to record, process, summarize and report financial information; and b)

Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrants internal control over financial reporting.

Date: November 5, 2020

/5/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)

Exhibit 31.5 RULE 1 3a-1 4(a)/i 5d-i 4(a) CERTIFICATION OF PRINCIPAL EXECUTIVE OFFICER OF AMEREN ILLINOIS COMPANY (required by Section 302 of the Sarbanes-Oxley Act of 2002)

I, Richard J. Mark, certify that:

i I have reviewed this report on Form iO-Q for the quarterly period ended September 30, 2020 of Ameren Illinois Company; 2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report; 3.

Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report; 4.

The registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules i3a-i5(e) and i5d-i5(e)) and internal control over financial reporting (as defined in Exchange Act Rules i3a-i5(f) and i5d-i5(f)) for the registrant and have:

a)

Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared; b)

Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles; c)

Evaluated the effectiveness of the registrants disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and d)

Disclosed in this report any change in the registrants internal control over financial reporting that occurred during the registrants most recent fiscal quarter (the registrants fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrants internal control over financial reporting; and 5.

The registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrants auditors and the audit committee of the registrants board of directors (or persons performing the equivalent functions):

a)

All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrants ability to record, process, summarize and report financial information; and b)

Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrants internal control over financial reporting.

Date: November 5, 2020

/5/ Richard ]. Mark Richard J. Mark Chairman and President (Principal Executive Officer)

Exhibit 31.6 RULE 13a-14(a)/15d-14(a) CERTIFICATION OF PRINCIPAL FINANCIAL OFFICER OF AMEREN ILLINOIS COMPANY (required by Section 302 of the Sarbanes-Oxley Act of 2002)

I, Michael L. Moehn, certify that:

1 I have reviewed this report on Form 1 0-Q for the quarterly period ended September 30, 2020 of Ameren Illinois Company; 2.

Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report; 3.

Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report; 4.

The registrants other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-1 5(f)) for the registrant and have:

a)

Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared; b)

Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles; c)

Evaluated the effectiveness of the registrants disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and d)

Disclosed in this report any change in the registrants internal control over financial reporting that occurred during the registrants most recent fiscal quarter (the registrants fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrants internal control over financial reporting; and 5.

The registrants other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrants auditors and the audit committee of the registrants board of directors (or persons performing the equivalent functions):

a)

All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrants ability to record, process, summarize and report financial information; and b)

Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrants internal control over financial reporting.

Date: November 5, 2020

/5/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)

Exhibit 32.1 SECTION 1350 CERTIFICATION OF THE PRINCIPAL EXECUTIVE OFFICER AND THE PRINCIPAL FINANCIAL OFFICER OF AMEREN CORPORATION (required by Section 906 of the Sarbanes-Oxley Act of 2002)

In connection with the report on Form 1 0-Q for the quarterly period ended September 30, 2020 of Ameren Corporation (the Registrant) as filed by the Registrant with the Securities and Exchange Commission on the date hereof (the Form 1 0-Q), each undersigned officer of the Registrant does hereby certify, pursuant to I 8 U.S.C. §1 350, as adopted pursuant to §906 of the Sarbanes-Oxley Act of 2002, that:

(1 )

The Form 10-Q fully complies with the requirements of Section 1 3(a) or 1 5(d) of the Securities Exchange Act of I 934 (1 5 U.S.C. 78m or 780(d)); and (2)

The information contained in the Form 1 0-Q fairly presents, in all material respects, the financial condition and results of operations of the Registrant.

Date: November 5, 2020

/5/ Warner L. Baxter Warner L. Baxter Chairman, President and Chief Executive Officer (Principal Executive Officer)

/5/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)

Exhibit 32.2 SECTION 1350 CERTIFICATION OF THE PRINCIPAL EXECUTIVE OFFICER AND THE PRINCIPAL FINANCIAL OFFICER OF UNION ELECTRIC COMPANY (required by Section 906 of the Sarbanes-Oxley Act of 2002)

In connection with the report on Form 10-Q for the quarterly period ended September 30, 2020 of Union Electric Company (the Registrant) as filed by the Registrant with the Securities and Exchange Commission on the date hereof (the Form 10-Q), each undersigned officer of the Registrant does hereby certify, pursuant to I 8 U.S.C. §1350, as adopted pursuant to §906 of the Sarbanes-Oxley Act of 2002, that:

(1 )

The Form I 0-Q fully complies with the requirements of Section 1 3(a) or I 5(d) of the Securities Exchange Act of I 934 (1 5 U.S.C. 78m or 780(d)); and (2)

The information contained in the Form 10-Q fairly presents, in all material respects, the financial condition and results of operations of the Registrant.

Date: November 5, 2020 Is? Martin J. Lyons, Jr.

Martin J. Lyons, Jr.

Chairman and President (Principal Executive Officer)

/5/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)

Exhibit 32.3 SECTION 1350 CERTIFICATION OF THE PRINCIPAL EXECUTIVE OFFICER AND THE PRINCIPAL FINANCIAL OFFICER OF AMEREN ILLINOIS COMPANY (required by Section 906 of the Sarbanes-Oxley Act of 2002)

In connection with the report on Form 10-Q for the quarterly period ended September 30, 2020 of Ameren Illinois Company (the Registrant) as filed by the Registrant with the Securities and Exchange Commission on the date hereof (the Form 10-Q), each undersigned officer of the Registrant does hereby certify, pursuant to 1 8 U.S.C. §1 350, as adopted pursuant to §906 of the Sarbanes-Oxley Act of 2002, that:

(1 )

The Form I 0-Q fully complies with the requirements of Section 1 3(a) or I 5(d) of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 780(d)); and (2)

The information contained in the Form 10-Q fairly presents, in all material respects, the financial condition and results of operations of the Registrant.

Date: November 5, 2020

/5/ Richard J. Mark Richard J. Mark Chairman and President (Principal Executive Officer)

/5/ Michael L. Moehn Michael L. Moehn Executive Vice President and Chief Financial Officer (Principal Financial Officer)