AEE / Ameren Corporation - Pengajuan SECLaporan Tahunan, Pernyataan Proksi

Up to $1,482,210,000 Common Stock

TABLE OF CONTENTS  Filed Pursuant to Rule 424(b)(5)  Registration Statement No. 333-274977 PROSPECTUS SUPPLEMENT (To Prospectus dated October 13, 2023) Up to $1,482,210,000 Common Stock We have entered into a sales agreement (as amended, the “sales agreement”) with Barclays Capital Inc., BofA Securities, Inc., Goldman Sachs & Co. LLC, J.P. Morgan Securities LLC, Mizuho Securities USA LLC, Morgan S

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 7, 2025 AMEREN CORPORATION

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 7, 2025 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State of other jurisdiction of incorporation) (Commission File Nu

Ameren Corporation Common Stock, $.01 Par Value Per Share First Amendment to Equity Distribution Sales Agreement

Exhibit 1 Ameren Corporation Common Stock, $.01 Par Value Per Share First Amendment to Equity Distribution Sales Agreement August 7, 2025 Barclays Capital Inc. 745 7th Avenue New York, New York 10019 BofA Securities, Inc. One Bryant Park New York, New York 10036 Goldman Sachs & Co. LLC 200 West Street New York, New York 10282 J.P. Morgan Securities LLC 383 Madison Avenue New York, New York 10179 M

Security Type

Calculation of Filing Fee Tables S-3 AMEREN CORP Table 1: Newly Registered and Carry Forward Securities ☐Not Applicable Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forward Form Type Carry Forward File Number Carry Forward Initial Effective Date Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward Newly Registered Securities Fees to be Paid 1 Equity Ameren Corporation Common Stock, $.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended June 30, 2025 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): July 31, 2025 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Num

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended June 30, Six Months Ended June 30, 2025 2024 2025 2024 Operating Revenues: Electric $ 2,038 $ 1,521 $ 3,660 $ 2,885 Natural gas 183 172 658 624 Total operating revenues 2,221 1,693 4,318 3,509 Operating Expenses: Fuel and purchased power 794 327 1,296 655 Nat

Ameren Announces Second Quarter 2025 Results

NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Financial Analysts and Institutional Investors Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces Second Quarter 2025 Results •Second Quarter Diluted Earnings Per Share were $1.01 in 2025 vs. $0.97 in 2024 •Reaffirm 2025 Diluted EPS Guida

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2024 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from      to      COMMISSION FILE NUMBER 1-14756 A.

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 12, 2025 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State of other jurisdiction of incorporation) (Commission File Numb

Forward Sale Agreement, dated May 12, 2025, between Ameren and Barclays Bank PLC, as a Forward Purchaser

Exhibit 10.3 May 12, 2025 To: Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 From: Barclays Bank PLC 1 Churchill Place London E14 5HP United Kingdom Telephone: +44 (0)20 7623 2323 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Avenue New York, NY 10019 Telephone: +1 212 526 7000 Dear Sirs, The purpose of this letter agreement (this “Confirmation”) is to con

Additional Forward Sale Agreement, dated May 13, 2025, between Ameren and JPMorgan Chase Bank, National Association, as a Forward Purchaser

Exhibit 10.6 May 13, 2025 To: Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 From: JPMorgan Chase Bank, National Association New York Branch 383 Madison Avenue New York, NY 10179 Dear Sirs, The purpose of this letter agreement (this “Confirmation”) is to confirm the terms and conditions of the transaction entered into between us on the Trade Date specified below (the “Transactio

Additional Forward Sale Agreement, dated May 13, 2025, between Ameren and Goldman Sachs & Co. LLC, as a Forward Purchaser

Exhibit 10.5 GOLDMAN SACHS & CO. LLC | 200 WEST STREET | NEW YORK, NEW YORK 10282-2198 | TEL: 212-902-1000 May 13, 2025 To: Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 Dear Sirs, The purpose of this letter agreement (this “Confirmation”) is to confirm the terms and conditions of the transaction entered into between us on the Trade Date specified below (the “Transaction”). Thi

Forward Sale Agreement, dated May 12, 2025, between Ameren and Wells Fargo Bank, National Association, as a Forward Purchaser

Exhibit 10.4 May 12, 2025 To: Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 From: Wells Fargo Bank, National Association 30 Hudson Yards New York, NY 10001-2170 Email: [email protected] Dear Sirs, The purpose of this letter agreement (this “Confirmation”) is to confirm the terms and conditions of the transaction entered into between us on the Trade

Forward Sale Agreement, dated May 12, 2025, between Ameren and Goldman Sachs & Co. LLC, as a Forward Purchaser

Exhibit 10.1 GOLDMAN SACHS & CO. LLC | 200 WEST STREET | NEW YORK, NEW YORK 10282-2198 | TEL: 212-902-1000 May 12, 2025 To: Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 Dear Sirs, The purpose of this letter agreement (this “Confirmation”) is to confirm the terms and conditions of the transaction entered into between us on the Trade Date specified below (the “Transaction”). Thi

Additional Forward Sale Agreement, dated May 13, 2025, between Ameren and Barclays Bank PLC, as a Forward Purchaser

Exhibit 10.7 May 13, 2025 To: Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 From: Barclays Bank PLC 1 Churchill Place London E14 5HP United Kingdom Telephone: +44 (0)20 7623 2323 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Avenue New York, NY 10019 Telephone: +1 212 526 7000 Dear Sirs, The purpose of this letter agreement (this “Confirmation”) is to con

Additional Forward Sale Agreement, dated May 13, 2025, between Ameren and Wells Fargo Bank, National Association, as a Forward Purchaser

Exhibit 10.8 May 13, 2025 To: Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 From: Wells Fargo Bank, National Association 30 Hudson Yards New York, NY 10001-2170 Email: [email protected] Dear Sirs, The purpose of this letter agreement (this “Confirmation”) is to confirm the terms and conditions of the transaction entered into between us on the Trade

Forward Sale Agreement, dated May 12, 2025, between Ameren and JPMorgan Chase Bank, National Association, as a Forward Purchaser

Exhibit 10.2 May 12, 2025 To: Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 From: JPMorgan Chase Bank, National Association New York Branch 383 Madison Avenue New York, NY 10179 Dear Sirs, The purpose of this letter agreement (this “Confirmation”) is to confirm the terms and conditions of the transaction entered into between us on the Trade Date specified below (the “Transactio

Underwriting Agreement, dated May 12, 2025, among Ameren, the Underwriters, the Forward Purchasers and the Forward Sellers.

  Exhibit 1   Ameren Corporation   Common Stock, $.01 Par Value Per Share   Underwriting Agreement   May 12, 2025   Goldman Sachs & Co. LLC 200 West Street New York, New York 10282   J.P. Morgan Securities LLC 383 Madison Avenue New York, New York 10179   Barclays Capital Inc. 745 Seventh Avenue New York, New York 10019   Wells Fargo Securities, LLC 500 West 33rd Street, 14th Floor New York, New Y

Table 1: Newly Registered and Carry Forward Securities

Calculation of Filing Fee Tables S-3 AMEREN CORP Table 1: Newly Registered and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forward Form Type Carry Forward File Number Carry Forward Initial Effective Date Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward Newly Registered Securities Fees to be Paid 1 Equity Ameren Corporation's Common Stock, $.

5,550,416 Shares Common Stock

TABLE OF CONTENTS  Filed pursuant to Rule 424(b)(2)  Registration No. 333-274977 PROSPECTUS SUPPLEMENT (To Prospectus dated October 13, 2023) 5,550,416 Shares Common Stock The forward sellers referred to below are offering 5,550,416 shares of our common stock, $.01 par value per share. We have entered into forward sale agreements with each of Goldman Sachs & Co. LLC, JPMorgan Chase Bank, National

SUBJECT TO COMPLETION, DATED MAY 12, 2025

TABLE OF CONTENTS The information contained in this preliminary prospectus supplement is not complete and may be changed.

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 8, 2025 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756 Am

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended March 31, 2025 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of

Ameren Announces First Quarter 2025 Results

NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces First Quarter 2025 Results •First Quarter GAAP Diluted Earnings Per Share were $1.07 in 2025 vs. $0.98 in 2024 •First Quarter Adjusted (Non-GAAP) Diluted Earnings Per Share were

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended March 31, 2025 2024 Operating Revenues: Electric $ 1,622 $ 1,364 Natural gas 475 452 Total operating revenues 2,097 1,816 Operating Expenses: Fuel and purchased power 502 328 Natural gas purchased for resale 169 151 Other operations and maintenance 485 470 De

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 1, 2025 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Numbe

U.S. Securities and Exchange Commission Washington, DC 20549 Notice of Exempt Solicitation Submitted Pursuant to Rule 14a-6(g)

U.S. Securities and Exchange Commission Washington, DC 20549 Notice of Exempt Solicitation Submitted Pursuant to Rule 14a-6(g) 1. Name of the Registrant: Ameren Corporation 2. Name of person relying on exemption: The Comptroller of the City of New York, on behalf of the New York City Employees’ Retirement System, the New York City Teachers’ Retirement Systems, and the New York City Police Pension

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): April 22, 2025 AMEREN CORPORATION (Exact Name of Registrant as Specified in Charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Number

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a party other than the Registrant ¨ Check the appropriate box: ¨ Preliminary Proxy Statement ¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ¨ Defin

Supplemental Indenture, dated March 1, 2025, by and between Ameren Missouri and The Bank of New York Mellon, as successor trustee, relating to the 5.25% First Mortgage Bonds due 2035.

Exhibit 4.2 SUPPLEMENTAL INDENTURE DATED MARCH 1, 2025 UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE (SUPPLEMENTAL TO THE INDENTURE OF MORTGAGE AND DEED OF TRUST DATED JUNE 15, 1937, AS AMENDED, EXECUTED BY UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE) 5.25% First Mortgage Bonds due 2035 This instrument was prepared by Stephen C. Lee, Esq., Vice President,

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): April 4, 2025 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Underwriting Agreement relating to the Bonds, dated March 26, 2025, between Ameren Missouri and the several underwriters named therein, for whom Goldman Sachs & Co. LLC, RBC Capital Markets, LLC, Scotia Capital (USA) Inc. and SMBC Nikko Securities America, Inc. are acting as representatives.

Exhibit 1 Union Electric Company First Mortgage Bonds due 2035 Underwriting Agreement March 26, 2025 Goldman Sachs & Co.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a party other than the Registrant ¨ Check the appropriate box: ¨ Preliminary Proxy Statement ¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ¨ Defin

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): March 24, 2025 AMEREN CORPORATION (Exact Name of Registrant as Specified in Charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Number

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.   )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.   ) Filed by the Registrant ☒ Filed by a party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a party other than the Registrant ¨ Check the appropriate box: ¨ Preliminary Proxy Statement ¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ¨ Defin

Underwriting Agreement, dated February 27, 2025, between Ameren and the several underwriters named therein, for whom Barclays Capital Inc., J.P. Morgan Securities LLC, Mizuho Securities USA LLC, MUFG Securities Americas Inc. and Wells Fargo Securities, LLC are acting as representatives.

Exhibit 1 Ameren Corporation $750,000,000 5.375% Senior Notes due 2035 Underwriting Agreement February 27, 2025 Barclays Capital Inc. 745 Seventh Avenue New York, New York 10019 J.P. Morgan Securities LLC 383 Madison Avenue New York, New York 10179 Mizuho Securities USA LLC 1271 Avenue of the Americas New York, New York 10020 MUFG Securities Americas Inc. 1221 Avenue of the Americas, 6th Floor New

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): March 7, 2025 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Num

Ameren Indenture Company Order, dated March 7, 2025, establishing the 5.375% Senior Notes due 2035

Exhibit 4.3 AMEREN CORPORATION Company Order March 7, 2025 The Bank of New York Mellon Trust Company, N.A., as Trustee 311 S. Wacker Drive Suite 6200B, Mailbox #44 Chicago, Illinois 60606 Re:          5.375% Senior Notes due 2035 Ladies and Gentlemen: Application is hereby made to The Bank of New York Mellon Trust Company, N.A., a national banking association, as successor trustee (the “Trustee”),

Global Notes.

Exhibit 4.4 REGISTERED REGISTERED THIS NOTE IS A GLOBAL NOTE REGISTERED IN THE NAME OF THE DEPOSITARY (REFERRED TO HEREIN) OR A NOMINEE THEREOF AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE FOR THE INDIVIDUAL NOTES REPRESENTED HEREBY AS PROVIDED IN THE INDENTURE REFERRED TO BELOW, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE O

Underwriting Agreement relating to the Bonds, dated February 24, 2025, between Ameren Illinois and the several underwriters named therein, for whom BNY Mellon Capital Markets, LLC, BofA Securities, Inc., Morgan Stanley & Co. LLC and Truist Securities, Inc. are acting as representatives.

Exhibit 1.1 Ameren Illinois Company First Mortgage Bonds due 2055 Underwriting Agreement February 24, 2025 BNY Mellon Capital Markets, LLC BofA Securities, Inc. Morgan Stanley & Co. LLC Truist Securities, Inc. As Representatives of the several Underwriters named in Schedule I to the applicable Pricing Agreement  c/o BNY Mellon Capital Markets, LLC 240 Greenwich Street, 3W New York, New York 10286

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): March 3, 2025 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Supplemental Indenture, dated as of February 1, 2025, by and between Ameren Illinois and The Bank of New York Mellon Trust Company, N.A., as successor trustee, relating to the Bonds.

Exhibit 4.2 WHEN RECORDED MAIL TO: Ameren Illinois Company Jonathan T. Shade One Ameren Plaza (MC 1310) 1901 Chouteau Avenue St. Louis, MO 63103 AMEREN ILLINOIS COMPANY (SUCCESSOR TO ILLINOIS POWER COMPANY) TO THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. AS SUCCESSOR TRUSTEE TO HARRIS TRUST AND SAVINGS BANK SUPPLEMENTAL INDENTURE DATED AS OF FEBRUARY 1, 2025 TO GENERAL MORTGAGE INDENTURE AND DE

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): February 26, 2025 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14

$750,000,000 5.375% Senior Notes due 2035

TABLE OF CONTENTS   Filed pursuant to Rule 424(b)(2)  Registration No. 333-274977 PROSPECTUS SUPPLEMENT (To Prospectus dated October 13, 2023) $750,000,000 5.375% Senior Notes due 2035 Ameren Corporation is offering $750,000,000 principal amount of its 5.375% Senior Notes due 2035, referred to in this prospectus supplement as the “senior notes.” The senior notes will mature on March 15, 2035. We w

Table 1: Newly Registered and Carry Forward Securities

Calculation of Filing Fee Tables S-3 AMEREN CORP Table 1: Newly Registered and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forward Form Type Carry Forward File Number Carry Forward Initial Effective Date Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward Newly Registered Securities Fees to be Paid 1 Debt Ameren Corporation's 5.

Filed Pursuant to Rule 433

Filed Pursuant to Rule 433 Registration No. 333-274977 Ameren Corporation Pricing Term Sheet February 27, 2025 Issue: 5.375% Senior Notes due 2035 (the “Notes”) Principal Amount: $750,000,000 Coupon (Interest Rate): 5.375% per annum Maturity Date: March 15, 2035 Benchmark Treasury: 4.625% due February 15, 2035 Benchmark Treasury Price: 102-20 Benchmark Treasury Yield: 4.298% Spread to Benchmark Tr

SUBJECT TO COMPLETION, DATED FEBRUARY 27, 2025

TABLE OF CONTENTS The information contained in this preliminary prospectus supplement is not complete and may be changed.

*Formula for Determining 2025 Target Performance Share Unit and Restricted Stock Unit Awards to be Issued to Named Executive Officers

Exhibit 10.29 FORMULA FOR DETERMINING 2025 TARGET PSU AND RSU AWARDS FORMULA FOR DETERMINING 2025 TARGET PERFORMANCE SHARE UNIT ("PSU") AND RESTRICTED STOCK UNIT ("RSU") AWARDS TO BE ISSUED TO NAMED EXECUTIVE OFFICERS The target number of PSUs and RSUs to be issued to each Named Executive Officer listed below for 2025 will be determined in accordance with the following formula: 2025 Target Number

*Form of Performance Share Unit Award Agreement (Relative Total Shareholder Return metric) for awards issued in 2025 pursuant to 2022 Omnibus Incentive Compensation Plan

PSU Award - TSR Exhibit 10.47 2025 Performance Share Unit Award Agreement Notice of 2025 Performance Share Unit Award (TSR) Participant: Grant Date: You have been granted the following Performance Share Units in accordance with the terms of the Ameren Corporation 2022 Omnibus Incentive Compensation Plan (as the same may be amended from time to time, the "Plan") and the attached award agreement, re

*Form of Performance Share Unit Award Agreement (Clean Energy Transition metric) for awards issued in 2025 pursuant to 2022 Omnibus Incentive Compensation Plan

PSU Award- Clean Energy Metric 305903566v.2 Exhibit 10.48 2025 Performance Share Unit Award Agreement Notice of 2025 Performance Share Unit Award (Clean Energy Transition) Participant: Grant Date: You have been granted the following Performance Share Units in accordance with the terms of the Ameren Corporation 2022 Omnibus Incentive Compensation Plan (as the same may be amended from time to time,

Powers of Attorney with respect to Ameren

Exhibit 24.1 POWER OF ATTORNEY WHEREAS, AMEREN CORPORATION, a Missouri corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2024; and WHEREAS, each of the individuals identified below is a director of

*Revised Schedule I to Second Amended and Restated Ameren Change of Control Severance Plan, as amended

Exhibit 10.22 SCHEDULE I CHANGE OF CONTROL SEVERANCE PLAN PARTICIPANTS EFFECTIVE DECEMBER 13, 2024 Benefit Level1 - 3 Birk, Mark C. Moehn, Michael Diya, Fadi Nwamu, Chonda * Lyons, Martin J. Singh, Leonard * Benefit Level1 - 2 Schukar, Shawn E. * Not eligible for excise tax gross-up provisions (for new officers effective on or after October 1, 2009) 1 Severance benefits include: •Cash severance, d

Subsidiaries of Ameren

Exhibit 21.1 SUBSIDIARIES OF AMEREN CORPORATION AT DECEMBER 31, 2024 Name State or Jurisdiction of Organization Ameren Corporation Missouri Ameren Development Company Missouri Missouri Central Railroad Company Delaware QST Enterprises Inc. Illinois Ameren EIP Investment, LLC Delaware Ameren Accelerator Investments, LLC Delaware AmerenEnergy Medina Valley Cogen, L.L.C. Illinois Ameren Transmission

*2025 Base Salary Table for Named Executive Officers

Exhibit 10.19 2025 BASE SALARY TABLE FOR NAMED EXECUTIVE OFFICERS The 2025 annual base salaries of the following Named Executive Officers of Ameren Corporation (“Ameren”), Union Electric Company (“UE”) and Ameren Illinois Company (“AIC”) (which officers are employed by Ameren and/or an Ameren subsidiary as of February 18, 2025, and were determined to the extent applicable by reference to the Amere

Ameren Corporation Insider Trading Policy

Exhibit 19.1 Ameren Corporation Insider Trading Policy I.Purpose Ameren Corporation (including its direct and indirect subsidiaries, “Ameren” or the “Company”) has adopted this Insider Trading Policy (this “Policy”) to promote compliance with applicable laws that prohibit certain persons who are aware of Material Nonpublic Information (as defined below) about a company from: (i) trading in securit

*2025 Ameren Short-Term Incentive Plan

EXHIBIT 10.15 2025 Ameren Short-Term Incentive Plan Plan Summary Effective January 1, 2025 1 EXHIBIT 10.15 2 EXHIBIT 10.15 Summary The Ameren Short-Term Incentive Plan (“STIP”) is intended to reward eligible Officers for their contributions to Ameren’s success. The STIP rewards Officers for results in the following categories: financial performance, safety, operational performance, customer, econo

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the fiscal year ended December 31, 2024 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of regi

Powers of Attorney with respect to Ameren Missouri

Exhibit 24.2 POWER OF ATTORNEY WHEREAS, UNION ELECTRIC COMPANY, a Missouri corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2024; and WHEREAS, each of the individuals identified below is a director

Powers of Attorney with respect to Ameren Illinois

Exhibit 24.3 POWER OF ATTORNEY WHEREAS, AMEREN ILLINOIS COMPANY, an Illinois corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2024; and WHEREAS, each of the individuals identified below is a direct

“Form of Restrictive Stock Unit Award Agreement for awards issued in 2025 pursuant to 2022 Omnibus Incentive Compensation Plan

RSU CEO Award 90286995v.6 Exhibit 10.49 2025 Restricted Stock Unit Award Agreement 59961097v.2 90286995v.6 Notice of 2025 Restricted Stock Unit Award Participant: Grant Date: You have been granted the following Restricted Stock Units in accordance with the terms of the Ameren Corporation 2022 Omnibus Incentive Compensation Plan (as the same may be amended from time to time, the "Plan") and the att

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended December 31, Year Ended December 31, 2024 2023 2024 2023 Operating Revenues: Electric $ 1,620 $ 1,343 $ 6,540 $ 6,439 Natural gas 321 275 1,083 1,061 Total operating revenues 1,941 1,618 7,623 7,500 Operating Expenses: Fuel and purchased power 527 294 1,681 1

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): February 13, 2025 AMEREN CORPORAT

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): February 13, 2025 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File

Ameren Announces 2024 Results, Affirms Guidance for 2025 Earnings and Issues Long-Term Growth Guidance

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts Media Investors Tony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces 2024 Results, Affirms Guidance for 2025 Earnings and Issues Long-Term Growth Guidance •2024 GAAP Diluted Earnings Per Share (EPS) were $4.42 vs. $4.38 in 2023 •2024 Adj

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): January 30, 2025 AMEREN CORPORATION (Exact Name of Registrant as Specified in Charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Numb

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 19, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14

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Exhibit 99.1 1901 Chouteau Avenue : St. Louis, MO 63103 : Ameren.com Contacts: Media Ameren Communications 314.554.2182 [email protected] Analysts Andrew Kirk 314.554.3942 [email protected] FOR IMMEDIATE RELEASE Steven Vondran joins Ameren board of directors ST. LOUIS (Dec. 16, 2024) — Ameren Corporation (NYSE: AEE) announced today that Steven O. Vondran has been elected to the Ameren board

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 13, 2024 AMEREN CORPORATION (Exact Name of Registrant as Specified in Charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Num

Note Purchase Agreement, dated as of August 30, 2024, between Ameren Transmission Company of Illinois and the several purchasers named therein.

Exhibit 4.1 Execution Version Ameren Transmission Company of Illinois $140,000,000 $70,000,000 5.17% Senior Notes, Series A, due September 1, 2039 and $70,000,000 5.42% Senior Notes, Series B, due September 1, 2053 Note Purchase Agreement Dated as of August 30, 2024 Table of Contents Section Heading Page Section 2. Sale and Purchase of Notes 1 Section 3. Closing 2 Section 4. Conditions to Closing

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended September 30, 2024 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact nam

Ameren Announces Third Quarter 2024 Results

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces Third Quarter 2024 Results •Third Quarter GAAP Diluted Earnings Per Share (EPS) were $1.70 in 2024 vs. $1.87 in 2023 •Third Quarter Adjusted (Non-GAAP) Diluted Earni

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): November 6, 2024 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended September 30, Nine Months Ended September 30, 2024 2023 2024 2023 Operating Revenues: Electric $ 2,035 $ 1,921 $ 4,920 $ 5,096 Natural gas 138 139 762 786 Total operating revenues 2,173 2,060 5,682 5,882 Operating Expenses: Fuel and purchased power 499 430 1,

AEE / Ameren Corporation / STATE STREET CORP Passive Investment

SC 13G/A 1 AmerenCorp.htm SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* AMEREN CORP (Name of Issuer) COMMON STOCK (Title of Class of Securities) 023608102 (CUSIP Number) September 30, 2024 (Date of Event Which Requires Filing of This Statement) Check the appropriate box to designate the rule pursuant to which this

Supplemental Indenture, dated September 1, 2024, by and between Ameren Missouri and The Bank of New York Mellon, as successor trustee, relating to the 5.125% First Mortgage Bonds due 2055.

Exhibit 4.2 SUPPLEMENTAL INDENTURE DATED SEPTEMBER 1, 2024 UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE (SUPPLEMENTAL TO THE INDENTURE OF MORTGAGE AND DEED OF TRUST DATED JUNE 15, 1937, AS AMENDED, EXECUTED BY UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE) 5.125% First Mortgage Bonds due 2055 This instrument was prepared by Chonda J. Nwamu, Esq., Executive

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): October 7, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-1475

Underwriting Agreement relating to the Bonds, dated September 30, 2024, between Ameren Missouri and the several underwriters named therein, for whom Barclays Capital Inc., BofA Securities, Inc., J.P. Morgan Securities LLC and Morgan Stanley & Co. LLC are acting as representatives.

Exhibit 1 Union Electric Company First Mortgage Bonds due 2055 Underwriting Agreement September 30, 2024 Barclays Capital Inc.

Ameren Corporation By-Laws, as amended effective August 9, 2024

Exhibit 3.1 AMEREN CORPORATION BY-LAWS As Amended Effective August 9, 2024 Article I Shareholders Section 1.                The annual meeting of the shareholders of Ameren Corporation (the "Company") shall be held on the second Thursday of May in each year (or if said day be a legal holiday, then on the next succeeding day not a legal holiday), at the registered office of the Company in the City

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 9, 2024 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Nu

Separation Agreement and General Release, effective April 5, 2024, between Bhavani Amirthalingam and Ameren Services Company

Exhibit 10.1 CONFIDENTIAL SEPARATION AGREEMENT AND GENERAL RELEASE This Confidential Separation Agreement and General Release (“Agreement”) is entered into by and between Bhavani Amirthalingam (“Employee”) and Ameren Services Company, a Missouri corporation, on behalf of itself and any parent company, subsidiary, division or affiliate entity (collectively, “Ameren”). RECITALS A.Employee has been e

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended June 30, 2024 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended June 30, Six Months Ended June 30, 2024 2023 2024 2023 Operating Revenues: Electric $ 1,521 $ 1,585 $ 2,885 $ 3,175 Natural gas 172 175 624 647 Total operating revenues 1,693 1,760 3,509 3,822 Operating Expenses: Fuel and purchased power 327 480 655 1,088 Nat

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 1, 2024 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Nu

Ameren Announces Second Quarter 2024 Results

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces Second Quarter 2024 Results •Second quarter Diluted Earnings Per Share were $0.97 in 2024 vs. $0.90 in 2023 •Guidance Range for 2024 Reaffirmed at $4.52 to $4.72 per

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): June 28, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Underwriting Agreement relating to the Bonds, dated June 17, 2024, between Ameren Illinois and the several underwriters named therein, for whom Barclays Capital Inc., MUFG Securities Americas Inc., Scotia Capital (USA) Inc., TD Securities (USA) LLC and Wells Fargo Securities, LLC are acting as representatives.

Exhibit 1.1 Ameren Illinois Company First Mortgage Bonds due 2054 Underwriting Agreement June 17, 2024 Barclays Capital Inc. MUFG Securities Americas Inc. Scotia Capital (USA) Inc. TD Securities (USA) LLC Wells Fargo Securities, LLC As Representatives of the several Underwriters named in Schedule I to the applicable Pricing Agreement c/o Barclays Capital Inc. 745 Seventh Avenue New York, New York

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): June 27, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Supplemental Indenture, dated as of June 1, 2024, by and between Ameren Illinois and The Bank of New York Mellon Trust Company, N.A., as successor trustee, relating to the Bonds.

Exhibit 4.2 WHEN RECORDED MAIL TO: Ameren Illinois Company Jonathan T. Shade One Ameren Plaza (MC 1310) 1901 Chouteau Avenue St. Louis, MO 63103 AMEREN ILLINOIS COMPANY (SUCCESSOR TO ILLINOIS POWER COMPANY) TO THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. AS SUCCESSOR TRUSTEE TO HARRIS TRUST AND SAVINGS BANK SUPPLEMENTAL INDENTURE DATED AS OF JUNE 1, 2024 TO GENERAL MORTGAGE INDENTURE AND DEED O

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from       to       COMMISSION FILE NUMBER 1-14756 A.

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): June 20, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): June 20, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 9, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756 Am

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended March 31, 2024 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 2, 2024 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Numbe

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended March 31, 2024 2023 Operating Revenues: Electric $ 1,364 $ 1,590 Natural gas 452 472 Total operating revenues 1,816 2,062 Operating Expenses: Fuel and purchased power 328 608 Natural gas purchased for resale 151 208 Other operations and maintenance 470 448 De

Ameren Announces First Quarter 2024 Results

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces First Quarter 2024 Results •First quarter Diluted Earnings Per Share were $0.98 in 2024 vs. $1.00 in 2023 •Guidance Range for 2024 Affirmed at $4.52 to $4.72 per Dil

* * *

April 10, 2024 Securities and Exchange Commission Division of Corporation Finance Office of Energy & Transportation 100 F Street, N.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a party other than the Registrant ¨ Check the appropriate box: ¨ Preliminary Proxy Statement ¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ¨ Defin

Underwriting Agreement, dated March 25, 2024, between Ameren Missouri and the several underwriters named therein, for whom BNY Mellon Capital Markets, LLC, J.P. Morgan Securities LLC, Mizuho Securities USA LLC and U.S. Bancorp Investments, Inc. are acting as representatives.

Exhibit 1 Union Electric Company First Mortgage Bonds Underwriting Agreement March 25, 2024 BNY Mellon Capital Markets, LLC J.

Supplemental Indenture, dated March 1, 2024, by and between Ameren Missouri and The Bank of New York Mellon, as successor trustee, relating to the 5.20% First Mortgage Bonds due 2034.

Exhibit 4.2 SUPPLEMENTAL INDENTURE DATED MARCH 1, 2024 UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE (SUPPLEMENTAL TO THE INDENTURE OF MORTGAGE AND DEED OF TRUST DATED JUNE 15, 1937, AS AMENDED, EXECUTED BY UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE) 5.20% First Mortgage Bonds due 2034 This instrument was prepared by Chonda J. Nwamu, Esq., Executive Vice

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): April 4, 2024

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): April 4, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.    )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.    ) Filed by the Registrant ☒ Filed by a party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a party other than the Registrant ¨ Check the appropriate box: ¨ Preliminary Proxy Statement ¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ¨ Defin

*2024 Ameren Short-Term Incentive Plan

Exhibit 10.15 2024 Ameren Short-Term Incentive Plan Plan Summary Effective January 1, 2024 Contents Page Annual Performance Metrics 3 Definitions 4 Performance Achievement Levels 6 Base Award 6 Individual Performance Modifier 6 Individual Short-Term Incentive Payout 7 Confidential Information 9 Non-Solicitation 9 Impact on Incentive Award Payment 10 2 Summary The Ameren Short-Term Incentive Plan (

Powers of Attorney with respect to Ameren

Exhibit 24.1 POWER OF ATTORNEY WHEREAS, AMEREN CORPORATION, a Missouri corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2023; and WHEREAS, each of the individuals identified below is a director of

Powers of Attorney with respect to Ameren Missouri

Exhibit 24.2 POWER OF ATTORNEY WHEREAS, UNION ELECTRIC COMPANY, a Missouri corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2023; and WHEREAS, each of the individuals identified below is a director

*Form of Performance Share Unit Award Agreement (Relative Total Shareholder Return metric) for awards issued in 2024 pursuant to 2022 Omnibus Incentive Compensation Plan

Exhibit 10.45 2024 Performance Share Unit Award Agreement PSU Award - TSR Participant: Grant Date: You have been granted the following Performance Share Units in accordance with the terms of the Ameren Corporation 2022 Omnibus Incentive Compensation Plan (as the same may be amended from time to time, the "Plan") and the attached award agreement, referred to as Performance Share Unit Award Agreemen

*Form of Restrictive Stock Unit Award Agreement for awards issued in 2024 pursuant to 2022 Omnibus Incentive Compensation Plan

Exhibit 10.47 2024 Restricted Stock Unit Award Agreement RSU Annual Award Notice of 2024 Restricted Stock Unit Award Participant: Grant Date: You have been granted the following Restricted Stock Units in accordance with the terms of the Ameren Corporation 2022 Omnibus Incentive Compensation Plan (as the same may be amended from time to time, the "Plan") and the attached award agreement, referred t

Powers of Attorney with respect to Ameren Illinois

Exhibit 24.3 POWER OF ATTORNEY WHEREAS, AMEREN ILLINOIS COMPANY, an Illinois corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2023; and WHEREAS, each of the individuals identified below is a direct

*Revised Schedule I to Second Amended and Restated Ameren Change of Control Severance Plan, as amended

Exhibit 10.22 SCHEDULE I CHANGE OF CONTROL SEVERANCE PLAN PARTICIPANTS EFFECTIVE DECEMBER 15, 2023 Benefit Level1 - 3 Birk, Mark C. Moehn, Michael Diya, Fadi Nwamu, Chonda * Lyons, Martin J. Singh, Leonard * Benefit Level1 - 2 Amirthalingam, Bhavani * * Not eligible for excise tax gross-up provisions (for new officers effective on or after October 1, 2009) 1 Severance benefits include: •Cash sever

*Third Amendment to amended and restated Ameren Supplemental Retirement Plan, dated January 5, 2015

Exhibit 10.53 Third Amendment to the Ameren Supplemental Retirement Plan Amended and Restated Effective January 1, 2008 WHEREAS, Ameren Corporation ("Company") previously adopted the Ameren Supplemental Retirement Plan, as amended and restated effective January 1, 2008 (the "Plan"); and WHEREAS, the Company reserved the right to amend the Plan; and WHEREAS, the Company desires to amend the Plan to

*Formula for Determining 2024 Target Performance Share Unit and Restricted Stock Unit Awards to be Issued to Named Executive Officers

Exhibit 10.29 FORMULA FOR DETERMINING 2024 TARGET PSU AND RSU AWARDS FORMULA FOR DETERMINING 2024 TARGET PERFORMANCE SHARE UNIT ("PSU") AND RESTRICTED STOCK UNIT ("RSU") AWARDS TO BE ISSUED TO NAMED EXECUTIVE OFFICERS The target number of PSUs and RSUs to be issued to each Named Executive Officer listed below for 2024 will be determined in accordance with the following formula: 2024 Target Number

*2024 Base Salary Table for Named Executive Officers

Exhibit 10.19 2024 BASE SALARY TABLE FOR NAMED EXECUTIVE OFFICERS The 2024 annual base salaries of the following Named Executive Officers of Ameren Corporation (“Ameren”), Union Electric Company (“UE”) and Ameren Illinois Company (“AIC”) (which officers are employed by Ameren and/or an Ameren subsidiary as of February 16, 2024, and were determined to the extent applicable by reference to the Amere

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the fiscal year ended December 31, 2023 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of regi

Subsidiaries of Ameren

Exhibit 21.1 SUBSIDIARIES OF AMEREN CORPORATION AT DECEMBER 31, 2023 Name State or Jurisdiction of Organization Ameren Corporation Missouri Ameren Development Company Missouri Missouri Central Railroad Company Delaware QST Enterprises Inc. Illinois Ameren EIP Investment, LLC Delaware Ameren Accelerator Investments, LLC Delaware AmerenEnergy Medina Valley Cogen, L.L.C. Illinois Ameren Transmission

*Performance-Based Restricted Share Unit Award Agreement, dated as of November 1, 2023, between Ameren and Michael L. Moehn

Exhibit 10.48 2023 Performance Based Restricted Stock Unit Award Agreement PSU Award- TSR Metric98060243v.3 Participant: Michael Moehn Grant Date: November 1, 2023 You have been granted the following Performance Based Restricted Stock Units in accordance with the terms of the Ameren Corporation 2022 Omnibus Incentive Compensation Plan (as the same may be amended from time to time, the "Plan") and

*Fourth Amendment to amended and restated Ameren Supplemental Retirement Plan, dated November 3, 2015

Exhibit 10.54 FOURTH AMENDMENT TO THE AMEREN SUPPLEMENTAL RETIREMENT PLAN Amended and Restated Effective January 1, 2008 WHEREAS, Ameren Corporation ("Company") previously adopted the Ameren Supplemental Retirement Plan, as amended and restated effective January 1, 2008 (the "Plan"); and WHEREAS, the Company reserved the right to amend the Plan; and WHEREAS, the Company desires to amend the Plan t

*Ameren’s Deferred Compensation Plan as amended and restated effective January 1, 2023

Exhibit 10.10 AMEREN DEFERRED COMPENSATION PLAN AND PARTICIPANT SUMMARY AMENDED AND RESTATED EFFECTIVE AS OF JANUARY 1, 2023 87100518v.8 AMEREN DEFERRED COMPENSATION PLAN As Amended and Restated Effective January 1, 2023 WHEREAS, Ameren Corporation amended and restated the Ameren Corporation Deferred Compensation Plan (“Plan”) effective as of January 1, 2010; and WHEREAS, Ameren Corporation reserv

*Second Amendment to amended and restated Ameren Supplemental Retirement Plan, dated November 27, 2013

Exhibit 10.52 SECOND AMENDMENT TO THE AMEREN SUPPLEMENTAL RETIREMENT PLAN Amended and Restated Effective January 1, 2008 WHEREAS, Ameren Corporation ("Company") previously adopted the Ameren Supplemental Retirement Plan, as amended and restated effective January 1, 2008 (the "Plan"); and WHEREAS, the Company reserved the right to amend the Plan; and WHEREAS, the Company desires to amend the Plan t

*Fifth Amendment to amended and restated Ameren Supplemental Retirement Plan, dated October 13, 2023

Exhibit 10.55 FIFTH AMENDMENT TO THE AMEREN SUPPLEMENTAL RETIREMENT PLAN Amended and Restated Effective January 1, 2008 WHEREAS, Ameren Corporation ("Company") previously adopted the Ameren Supplemental Retirement Plan, as amended and restated effective January 1, 2008 (the "Plan"), and as subsequently amended by the First Amendment to the Ameren Supplemental Retirement Plan, dated October 24, 200

Ameren Corporation Financial Restatement Compensation Recoupment Policy, as adopted August 10, 2023

Exhibit 97.1 AMEREN CORPORATION FINANCIAL RESTATEMENT COMPENSATION RECOUPMENT POLICY This Ameren Corporation Financial Restatement Compensation Recoupment Policy (“Policy”) has been adopted by the Human Resources Committee of the Board of Directors (the “Board”) of Ameren Corporation as of August 10, 2023. This Policy provides for the recoupment of certain executive compensation in the event of an

*Form of Performance Share Unit Award Agreement (Clean Energy Transition metric) for awards issued in 2024 pursuant to 2022 Omnibus Incentive Compensation Plan

Exhibit 10.46 2024 Performance Share Unit Award Agreement PSU Award- Clean Energy Metric305903566v.2 Participant: Grant Date: You have been granted the following Performance Share Units in accordance with the terms of the Ameren Corporation 2022 Omnibus Incentive Compensation Plan (as the same may be amended from time to time, the "Plan") and the attached award agreement, referred to as Performanc

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended December 31, Year Ended December 31, 2023 2022 2023 2022 Operating Revenues: Electric $ 1,343 $ 1,610 $ 6,439 $ 6,581 Natural gas 275 436 1,061 1,376 Total operating revenues 1,618 2,046 7,500 7,957 Operating Expenses: Fuel 91 97 514 473 Purchased power 203 4

Ameren Announces 2023 Results and Issues Guidance for 2024 Earnings and Long-Term Growth

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts Media Investors Tony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces 2023 Results and Issues Guidance for 2024 Earnings and Long-Term Growth •2023 Diluted Earnings Per Share (EPS) were $4.38, Compared to $4.14 in 2022 •2024 Diluted EPS G

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): February 22, 2024 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File

AEE / Ameren Corporation / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv0012-amerencorp.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 14)* Name of issuer: Ameren Corp Title of Class of Securities: Common Stock CUSIP Number: 023608102 Date of Event Which Requires Filing of this Statement: December 29, 2023 Check the appropriate box to designate the rule pu

Supplemental Indenture to the Ameren Missouri Mortgage dated January 1, 2024, for 5.25% First Mortgage Bonds due 2054

Exhibit 4.2 SUPPLEMENTAL INDENTURE DATED JANUARY 1, 2024 UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE (SUPPLEMENTAL TO THE INDENTURE OF MORTGAGE AND DEED OF TRUST DATED JUNE 15, 1937, AS AMENDED, EXECUTED BY UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE) 5.25% First Mortgage Bonds due 2054 This instrument was prepared by Chonda J. Nwamu, Esq., Executive Vic

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): January 9, 2024 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-1475

Underwriting Agreement, dated January 3, 2024, between Ameren Missouri and the several underwriters named therein, for whom BofA Securities, Inc., RBC Capital Markets, LLC, SMBC Nikko Securities America, Inc. and Truist Securities, Inc. are acting as representatives.

Exhibit 1 Union Electric Company First Mortgage Bonds Underwriting Agreement January 3, 2024 BofA Securities, Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): December 21, 2023 AMEREN CORPORAT

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): December 21, 2023 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File

Global Notes.

Exhibit 4.4 REGISTERED REGISTERED THIS NOTE IS A GLOBAL NOTE REGISTERED IN THE NAME OF THE DEPOSITARY (REFERRED TO HEREIN) OR A NOMINEE THEREOF AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE FOR THE INDIVIDUAL NOTES REPRESENTED HEREBY AS PROVIDED IN THE INDENTURE REFERRED TO BELOW, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE O

Ameren Indenture Company Order, dated December 21, 2023, establishing the 5.00% Senior Notes due 2029 (including the global note)

Exhibit 4.3 AMEREN CORPORATION Company Order December 21, 2023 The Bank of New York Mellon Trust Company, N.A., as Trustee 2 North LaSalle Street, Suite 700 Chicago, Illinois 60602 Re:         5.00% Senior Notes due 2029 Ladies and Gentlemen: Application is hereby made to The Bank of New York Mellon Trust Company, N.A., a national banking association, as successor trustee (the “Trustee”), under th

Underwriting Agreement, dated December 18, 2023, between Ameren and the several underwriters named therein, for whom Barclays Capital Inc., Goldman Sachs & Co. LLC, J.P. Morgan Securities LLC, Morgan Stanley & Co. LLC and MUFG Securities Americas Inc. are acting as representatives.

Exhibit 1 Execution Version Ameren Corporation $700,000,000 5.00% Senior Notes due 2029 Underwriting Agreement December 18, 2023 Barclays Capital Inc. 745 Seventh Avenue New York, New York 10019 Goldman Sachs & Co. LLC 200 West Street New York, New York 10282 J.P. Morgan Securities LLC 383 Madison Avenue New York, New York 10179 Morgan Stanley & Co. LLC 1585 Broadway, 29th Floor New York, New York

Calculation of Filing Fee Tables (1) Form 424(b)(2) (Form Type) Ameren Corporation (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities and Carry Forward Securities

Exhibit 107 Calculation of Filing Fee Tables (1) Form 424(b)(2) (Form Type) Ameren Corporation (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forward Form Type Carry Forward File Number Carry Forward Initial Effective Date Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward Newly Registered Securities Fees to Be Paid Debt Ameren Corporation’s 5.

$700,000,000 5.00% Senior Notes due 2029

TABLE OF CONTENTS  Filed pursuant to Rule 424(b)(2)  Registration No. 333-274977 PROSPECTUS SUPPLEMENT (To Prospectus dated October 13, 2023) $700,000,000 5.00% Senior Notes due 2029 Ameren Corporation is offering $700,000,000 principal amount of its 5.00% Senior Notes due 2029, referred to in this prospectus supplement as the “senior notes.” The senior notes will mature on January 15, 2029. We wi

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): December 15, 2023 AMEREN CORPORATION (Exact Name of Registrant as Specified in Charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Num

Ameren Corporation Pricing Term Sheet December 18, 2023

Filed Pursuant to Rule 433 Registration No. 333-274977 Ameren Corporation Pricing Term Sheet December 18, 2023 Issue: 5.00% Senior Notes due 2029 (the “Notes”) Principal Amount: $700,000,000 Coupon (Interest Rate): 5.00% per annum Maturity Date: January 15, 2029 Benchmark Treasury: 4.375% due November 30, 2028 Benchmark Treasury Price: 101-28+ Benchmark Treasury Yield: 3.950% Spread to Benchmark T

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): December 14, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14

SUBJECT TO COMPLETION, DATED DECEMBER 18, 2023

TABLE OF CONTENTS The information contained in this preliminary prospectus supplement is not complete and may be changed.

###

Exhibit 99.1 news release 1901 Chouteau Avenue : St. Louis, MO 63103 : Ameren.com Contacts: Media Ameren Communications 314.554.2182 [email protected] Analysts Andrew Kirk 314.554.3942 [email protected] For Immediate Release Kimberly Harris joins Ameren Board of Directors ST. LOUIS (Dec. 18, 2023) — The board of directors of Ameren Corporation (NYSE: AEE) announced today that Kimberly J. Ha

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): November 16, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14

Global Notes.

Exhibit 4.4 REGISTERED REGISTERED THIS NOTE IS A GLOBAL NOTE REGISTERED IN THE NAME OF THE DEPOSITARY (REFERRED TO HEREIN) OR A NOMINEE THEREOF AND, UNLESS AND UNTIL IT IS EXCHANGED IN WHOLE FOR THE INDIVIDUAL NOTES REPRESENTED HEREBY AS PROVIDED IN THE INDENTURE REFERRED TO BELOW, THIS NOTE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY THE DEPOSITARY TO A NOMINEE OF THE DEPOSITARY OR BY A NOMINEE O

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): November 20, 2023 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File

Ameren Indenture Company Order, dated November 20, 2023, establishing the 5.70% Senior Notes due 2026 (including the global note)

Exhibit 4.3 AMEREN CORPORATION Company Order November 20, 2023 The Bank of New York Mellon Trust Company, N.A., as Trustee 2 North LaSalle Street, Suite 700 Chicago, Illinois 60602 Re: 5.70% Senior Notes due 2026 Ladies and Gentlemen: Application is hereby made to The Bank of New York Mellon Trust Company, N.A., a national banking association, as successor trustee (the “Trustee”), under the Indent

Underwriting Agreement, dated November 15, 2023, between Ameren and the several underwriters named therein, for whom Barclays Capital Inc., Goldman Sachs & Co. LLC, J.P. Morgan Securities LLC, Mizuho Securities USA LLC and Wells Fargo Securities, LLC are acting as representatives.

Exhibit 1 Execution Version Ameren Corporation $600,000,000 5.70% Senior Notes due 2026 Underwriting Agreement November 15, 2023 Barclays Capital Inc. 745 Seventh Avenue New York, New York 10019 Goldman Sachs & Co. LLC 200 West Street New York, New York 10282 J.P. Morgan Securities LLC 383 Madison Avenue New York, New York 10179 Mizuho Securities USA LLC 1271 Avenue of the Americas New York, New Y

$600,000,000 5.70% Senior Notes due 2026

TABLE OF CONTENTS  Filed pursuant to Rule 424(b)(2)  Registration No. 333-274977 PROSPECTUS SUPPLEMENT (To Prospectus dated October 13, 2023) $600,000,000 5.70% Senior Notes due 2026 Ameren Corporation is offering $600,000,000 principal amount of its 5.70% Senior Notes due 2026, referred to in this prospectus supplement as the “senior notes.” The senior notes will mature on December 1, 2026. We wi

Calculation of Filing Fee Tables (1) Form 424(b)(2) (Form Type) Ameren Corporation (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities and Carry Forward Securities

Exhibit 107 Calculation of Filing Fee Tables (1) Form 424(b)(2) (Form Type) Ameren Corporation (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forward Form Type Carry Forward File Number Carry Forward Initial Effective Date Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward Newly Registered Securities Fees to Be Paid Debt Ameren Corporation’s 5.

SUBJECT TO COMPLETION, DATED NOVEMBER 15, 2023

TABLE OF CONTENTS The information contained in this preliminary prospectus supplement is not complete and may be changed.

Ameren Corporation Pricing Term Sheet November 15, 2023

Filed Pursuant to Rule 433 Registration No. 333-274977 Ameren Corporation Pricing Term Sheet November 15, 2023 Issue: 5.70% Senior Notes due 2026 (the “Notes”) Principal Amount: $600,000,000 Coupon (Interest Rate): 5.70% per annum Maturity Date: December 1, 2026 Benchmark Treasury: 4.625% due November 15, 2026 Benchmark Treasury Price: 99-25 ¾ Benchmark Treasury Yield: 4.696% Spread to Benchmark T

Up to $907,700,000 Common Stock

TABLE OF CONTENTS  Filed pursuant to Rule 424(b)(5)  Registration No. 333-274977 PROSPECTUS SUPPLEMENT (To Prospectus dated October 13, 2023) Up to $907,700,000 Common Stock We have entered into a sales agreement with Barclays Capital Inc., BofA Securities, Inc., Goldman Sachs & Co. LLC, J.P. Morgan Securities LLC, Mizuho Securities USA LLC, Morgan Stanley & Co. LLC, MUFG Securities Americas Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended September 30, 2023 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact nam

Ameren Announces Third Quarter 2023 Results

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces Third Quarter 2023 Results •Third Quarter Diluted Earnings Per Share were $1.87 in 2023 vs. $1.74 in 2022 •Guidance Range for 2023 Narrowed to $4.30 to $4.45 per Dil

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended September 30, Nine Months Ended September 30, 2023 2022 2023 2022 Operating Revenues: Electric $ 1,921 $ 2,140 $ 5,096 $ 4,971 Natural gas 139 166 786 940 Total operating revenues 2,060 2,306 5,882 5,911 Operating Expenses: Fuel 158 117 423 376 Purchased powe

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): November 8, 2023 AMEREN CORPORATI

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): November 8, 2023 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 11-K/A Amendment No. 1

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 11-K/A Amendment No.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 11-K/A Amendment No. 1

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 11-K/A Amendment No.

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K/A Amendment No. 1

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K/A Amendment No.

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K/A Amendment No. 1

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K/A Amendment No.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 11-K/A Amendment No. 1

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 11-K/A Amendment No.

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K/A Amendment No. 1

11-K/A Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K/A Amendment No.

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): October 12, 2023 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State of other jurisdiction of incorporation (Commission File N

Form T-1 statement of eligibility of The Bank of New York Mellon Trust Company, N.A. as the trustee under Ameren Illinois Company’s General Mortgage Indenture and Deed of Trust, dated as of November 1, 1992.

Exhibit 25.8 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE PURSUANT TO SECTION 305(b)(2) ¨ THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. (Exact name of trustee as specified in its charter) (Ju

Form T-1 statement of eligibility of The Bank of New York Mellon as the trustee under Union Electric Company’s Indenture, dated as of August 15, 2002.

Exhibit 25.4 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE PURSUANT TO SECTION 305(b)(2) ¨ THE BANK OF NEW YORK MELLON (Exact name of trustee as specified in its charter) New York (Jurisdiction

Ameren Power of Attorney.

Exhibit 24.1 POWER OF ATTORNEY WHEREAS, AMEREN CORPORATION, a Missouri corporation (herein referred to as the “Company”), intends to file with the Securities and Exchange Commission, under the Securities Act of 1933, as amended, a registration statement or registration statements on an appropriate form and any amendments thereto, which may be jointly filed with subsidiaries of the Company (the “Su

Consent of Morgan, Lewis & Bockius LLP (included in Exhibit 5.3).

Exhibit 5.3 October 13, 2023 Ameren Corporation Union Electric Company Ameren Illinois Company c/o Ameren Corporation 1901 Chouteau Avenue St. Louis, Missouri 63103 Ladies and Gentlemen: As counsel to Ameren Corporation, a Missouri corporation (“Ameren”), Union Electric Company, a Missouri corporation (“UE”), and Ameren Illinois Company, an Illinois corporation (“AIC”), we have participated in the

As filed with the Securities and Exchange Commission on October 13, 2023

TABLE OF CONTENTS As filed with the Securities and Exchange Commission on October 13, 2023 Registration Nos.

Form T-1 statement of eligibility of The Bank of New York Mellon as the trustee under Union Electric Company’s Indenture of Mortgage and Deed of Trust, dated June 15, 1937.

Exhibit 25.5 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE PURSUANT TO SECTION 305(b)(2) ¨ THE BANK OF NEW YORK MELLON (Exact name of trustee as specified in its charter) New York (Jurisdiction

Form T-1 statement of eligibility of The Bank of New York Mellon Trust Company, N.A. as the trustee under Ameren Illinois Company’s Indenture, dated as of June 1, 2006.

Exhibit 25.7 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE PURSUANT TO SECTION 305(b)(2) ¨ THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. (Exact name of trustee as specified in its charter) (Ju

Form T-1 statement of eligibility of The Bank of New York Mellon Trust Company, N.A. as the trustee under Ameren Corporation’s Indenture, dated as of December 1, 2001.

Exhibit 25.1 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE CHECK IF AN APPLICATION TO DETERMINE ELIGIBILITY OF A TRUSTEE PURSUANT TO SECTION 305(b)(2) ¨ THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. (Exact name of trustee as specified in its charter) (Ju

Filing Fee Table.

Exhibit 107 Calculation of Filing Fee Tables Form S-3 (Form Type) Ameren Corporation Union Electric Company Ameren Illinois Company (Exact Name of Registrants as Specified in their Charters) Table 1: Newly Registered Securities and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forward Form Type Carry Forward File Number Carry Forward Initial Effective Date Filing Fee Previously Paid in Connection with Unsold Securities to be Carried Forward Newly Registered Securities Fees to Be Paid Debt Ameren Corporation Senior Debt Securities Rule 457(r) (1) — — — $0.

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): September 26, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-1

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 10, 2023 AMEREN CORPORATIO

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 10, 2023 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation (Commission File Nu

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended June 30, 2023 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of

First Amendment, dated as of April 19, 2023, to Amended and Restated Credit Agreement, dated as of December 6, 2022, by and among Ameren, Ameren Missouri and JPMorgan Chase Bank, N.A., as agent and the lenders party thereto

Exhibit 10.1 EXECUTION VERSION FIRST AMENDMENT dated as of April 19, 2023 (this “Amendment”), among AMEREN CORPORATION, a Missouri corporation (the “Company”), UNION ELECTRIC COMPANY, d/b/a Ameren Missouri, a Missouri corporation (the “Borrowing Subsidiary” and, together with the Company, the “Borrowers”), the LENDERS party hereto and JPMORGAN CHASE BANK, N.A., as Administrative Agent. WHEREAS, re

First Amendment, dated as of April 19, 2023, to Amended and Restated Credit Agreement, dated as of December 6, 2022, by and among Ameren, Ameren Illinois and JPMorgan Chase Bank, N.A., as agent and the lenders party thereto

Exhibit 10.2 EXECUTION VERSION FIRST AMENDMENT dated as of April 19, 2023 (this “Amendment”), among AMEREN CORPORATION, a Missouri corporation (the “Company”), AMEREN ILLINOIS COMPANY, an Illinois corporation (the “Borrowing Subsidiary” and, together with the Company, the “Borrowers”), the LENDERS party hereto and JPMORGAN CHASE BANK, N.A., as Administrative Agent. WHEREAS, reference is made to th

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended June 30, Six Months Ended June 30, 2023 2022 2023 2022 Operating Revenues: Electric $ 1,585 $ 1,513 $ 3,175 $ 2,831 Natural gas 175 213 647 774 Total operating revenues 1,760 1,726 3,822 3,605 Operating Expenses: Fuel 152 83 265 259 Purchased power 328 318 82

Ameren Announces Second Quarter 2023 Results

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces Second Quarter 2023 Results •Second Quarter Diluted Earnings Per Share were $0.90 in 2023 vs. $0.80 in 2022 •Guidance Range for 2023 Reaffirmed at $4.25 to $4.45 per

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 2, 2023 AMEREN CORPORATION

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 2, 2023 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Nu

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K

11-K Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K ☒ ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to COMMISSION FILE NUMBER 1-14756 A.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 31, 2023

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 31, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756 A

Supplemental Indenture, dated as of May 1, 2023, by and between Ameren Illinois and The Bank of New York Mellon Trust Company, N.A., as successor trustee, relating to the Bonds.

Exhibit 4.2 WHEN RECORDED MAIL TO: Ameren Illinois Company Jonathan T. Shade One Ameren Plaza (MC 1310) 1901 Chouteau Avenue St. Louis, MO 63103 AMEREN ILLINOIS COMPANY (SUCCESSOR TO ILLINOIS POWER COMPANY) TO THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. AS SUCCESSOR TRUSTEE TO HARRIS TRUST AND SAVINGS BANK SUPPLEMENTAL INDENTURE DATED AS OF MAY 1, 2023 TO GENERAL MORTGAGE INDENTURE AND DEED OF

Underwriting Agreement relating to the Bonds, dated May 23, 2023, between Ameren Illinois and the several underwriters named therein, for whom MUFG Securities Americas Inc., PNC Capital Markets LLC, Scotia Capital (USA) Inc., SMBC Nikko Securities America, Inc. and Truist Securities, Inc. are acting as representatives.

EX-1.1 2 tm2317356d1ex1-1.htm EXHIBIT 1.1 Exhibit 1.1 Ameren Illinois Company First Mortgage Bonds due 2033 Underwriting Agreement May 23, 2023 MUFG Securities Americas Inc. PNC Capital Markets LLC Scotia Capital (USA) Inc. SMBC Nikko Securities America, Inc. Truist Securities, Inc. As Representatives of the several Underwriters named in Schedule I to the applicable Pricing Agreement c/o  MUFG Sec

As filed with the Securities and Exchange Commission on May 18, 2023

TABLE OF CONTENTS As filed with the Securities and Exchange Commission on May 18, 2023 Registration No.

Power of Attorney.

Exhibit 24 POWER OF ATTORNEY WHEREAS, Ameren Corporation, a Missouri corporation (the “Company”), intends to file with the Securities and Exchange Commission, under the Securities Act of 1933, as amended, a registration statement or registration statements on an appropriate form and any amendments thereto registering common stock under the Company’s Dividend Reinvestment and Stock Purchase Plan (DRPlus), as authorized by the Company’s Board of Directors on May 12, 2023; and WHEREAS, each of the below undersigned is a director of the Company; NOW, THEREFORE, each of the undersigned hereby constitutes and appoints Martin J.

Filing Fee Table

Exhibit 107 Calculation of Filing Fee Tables Form S-3 (Form Type) Ameren Corporation (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities and Carry Forward Securities Security type Security class title Fee calculation or carry forward rule Amount registered Proposed maximum offering price per unit Maximum aggregate offering price Fee rate Amount of registration fee Carry forward form type Carry forward file number Carry forward initial effective date Filing fee previously paid in connection with unsold securities to be carried forward Newly Registered Securities Fees to Be Paid — — — — — — — Fees Previously Paid — — — — — — — Carry Forward Securities Carry Forward Securities (2) Equity Common Stock, $.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 11, 2023

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 11, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756 A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ☒ Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended March 31, 2023 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended March 31, 2023 2022 Operating Revenues: Electric $ 1,590 $ 1,318 Natural gas 472 561 Total operating revenues 2,062 1,879 Operating Expenses: Fuel 113 176 Purchased power 495 177 Natural gas purchased for resale 208 293 Other operations and maintenance 448 46

Ameren Announces First Quarter 2023 Results

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces First Quarter 2023 Results •First Quarter Diluted Earnings Per Share were $1.00 in 2023 vs. $0.97 in 2022 •Guidance Range for 2023 Affirmed at $4.25 to $4.45 per Dil

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 4, 2023 AMEREN CORPORATION (E

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 4, 2023 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Numbe

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): April 7, 2023

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): April 7, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Ameren Corporation Vote FOR: Proxy Ballot Item #5 “Shareholder Proposal Regarding Scopes 1 & 2 Emissions Targets” Annual Meeting: May 11, 2023

Ameren Corporation Vote FOR: Proxy Ballot Item #5 “Shareholder Proposal Regarding Scopes 1 & 2 Emissions Targets” Annual Meeting: May 11, 2023 CONTACT: Mary Minette, Mercy Investment Services | mminette@Mercyinvestments.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.      )

TABLE OF CONTENTS UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No.      ) Filed by the Registrant ☒ Filed by a party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Ru

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. )

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a party other than the Registrant ¨ Check the appropriate box: ¨ Preliminary Proxy Statement ¨ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ¨ Defin

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): March 13, 2023

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): March 13, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Underwriting Agreement, dated February 27, 2023, between Ameren Missouri and the several underwriters named therein, for whom BofA Securities, Inc., KeyBanc Capital Markets Inc., RBC Capital Markets, LLC, TD Securities (USA) LLC and U.S. Bancorp Investments, Inc. are acting as representatives.

Exhibit 1 Union Electric Company First Mortgage Bonds Underwriting Agreement February 27, 2023 BofA Securities, Inc.

Supplemental Indenture to the Ameren Missouri Mortgage dated February 1, 2023, for 5.45% First Mortgage Bonds due 2053

Exhibit 4.2 SUPPLEMENTAL INDENTURE DATED FEBRUARY 1, 2023 UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE (SUPPLEMENTAL TO THE INDENTURE OF MORTGAGE AND DEED OF TRUST DATED JUNE 15, 1937, AS AMENDED, EXECUTED BY UNION ELECTRIC COMPANY TO THE BANK OF NEW YORK MELLON, AS TRUSTEE) 5.45% First Mortgage Bonds due 2053 This instrument was prepared by Chonda J. Nwamu, Esq., Senior Vice

Amended and Restated Tax Allocation Agreement, dated as of December 22, 2022

Exhibit 99.1 AMEREN CORPORATION AND ITS AFFILIATED CORPORATIONS AMENDED AND RESTATED TAX ALLOCATION AGREEMENT This Amended and Restated Tax Allocation Agreement (the "Agreement") is made effective as of December 22, 2022 by and among Ameren Corporation (“Ameren”), a Missouri Corporation, and its affiliated corporations, as identified in Exhibit A hereto (collectively, the "Group"; individually, "M

Amendment dated December 9, 2022 to Ameren’s Deferred Compensation Plan

Exhibit 10.12 FOURTH AMENDMENT TO THE AMEREN DEFERRED COMPENSATION PLAN Amended and Restated Effective January 1, 2010 WHEREAS, Ameren Corporation (“Company”) previously established and adopted the Ameren Deferred Compensation Plan, as amended and restated effective January 1, 2010 (the “Plan”), and as further amended by the First Amendment to the Ameren Deferred Compensation Plan, dated October 1

Powers of Attorney with respect to Ameren Illinois

Exhibit 24.3 POWER OF ATTORNEY WHEREAS, AMEREN ILLINOIS COMPANY, an Illinois corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2022; and WHEREAS, each of the individuals identified below is a direct

Form of Restrictive Stock Unit Award Agreement for awards issued in 2023 pursuant to 2022 Omnibus Incentive Compensation Plan

Exhibit 10.47 2023 Restricted Stock Unit Award Agreement 59961003v.4 78539999v.2 Ameren Corporation 2023 Restricted Stock Unit Award Agreement THIS AGREEMENT, effective as of the Grant Date set forth in the Notice of 2023 Restricted Stock Unit Award ("Notice"), represents the grant of Restricted Stock Units by Ameren Corporation (“Ameren”) to the Participant set forth in the Notice, pursuant to th

Powers of Attorney with respect to Ameren Missouri

Exhibit 24.2 POWER OF ATTORNEY WHEREAS, UNION ELECTRIC COMPANY, a Missouri corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2022; and WHEREAS, each of the individuals identified below is a director

Form of Performance Share Unit Award Agreement (Clean Energy Transition metric) for awards issued in 2023 pursuant to 2022 Omnibus Incentive Compensation Plan

Exhibit 10.46 2023 Performance Share Unit Award Agreement 59961003v.4 78539999v.2 Ameren Corporation 2023 Performance Share Unit Award Agreement (Clean Energy) THIS AGREEMENT, effective as of the Grant Date set forth in the Notice of 2023 Performance Share Unit Award (Clean Energy) ("Notice"), represents the grant of Performance Share Units by Ameren Corporation ( “Ameren”), to the Participant set

Amendment dated December 20, 2013 to Ameren’s Deferred Compensation Plan

Exhibit 10.11 THIRD AMENDMENT TO THE AMEREN DEFERRED COMPENSATION PLAN Amended and Restated Effective January 1, 2010 WHEREAS, Ameren Corporation ("Company") previously established and adopted the Ameren Deferred Compensation Plan, as amended and restated effective January 1, 2010 (the "Plan"); and WHEREAS, the Company reserved the right to amend the Plan; and WHEREAS, the Company desires to amend

Amendment dated November 27, 2013 to Ameren’s Deferred Compensation Plan

Exhibit 10.10 SECOND AMENDMENT TO THE AMEREN DEFERRED COMPENSATION PLAN Amended and Restated Effective January 1, 2010 WHEREAS, Ameren Corporation ("Company") previously established and adopted the Ameren Deferred Compensation Plan, as amended and restated effective January 1, 2010 (the "Plan"); and WHEREAS, the Company reserved the right to amend the Plan; and WHEREAS, the Company desires to amen

*Formula for Determining 2023 Target Performance Share Unit and Restricted Stock Unit Awards to be Issued to Named Executive Officers

Exhibit 10.31 FORMULA FOR DETERMINING 2023 TARGET PSU AND RSU AWARDS FORMULA FOR DETERMINING 2023 TARGET PERFORMANCE SHARE UNIT ("PSU") AND RESTRICTED STOCK UNIT ("RSU") AWARDS TO BE ISSUED TO NAMED EXECUTIVE OFFICERS The target number of PSUs and RSUs to be issued to each Named Executive Officer listed below for 2023 will be determined in accordance with the following formula: 2023 Target Number

*2023 Ameren Short-Term Incentive Plan

EXHIBIT 10.17 2023 Ameren Short-Term Incentive Plan Plan Summary Effective January 1, 2023 1 EXHIBIT 10.17 Contents Page Summary 3 Eligibility 3 Award Opportunities 3 Plan Structure 3 Annual Performance Metrics 3 Definitions 4 Performance Achievement Levels 6 Base Award 6 Individual Performance Modifier 6 Individual Short-Term Incentive Payout 7 Impact of Events 8 Confidentiality and Non-Solicitat

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-K ☒ Annual report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the fiscal year ended December 31, 2022 OR ☐ Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of regi

*2023 Base Salary Table for Named Executive Officers

Exhibit 10.21 2023 BASE SALARY TABLE FOR NAMED EXECUTIVE OFFICERS The 2023 annual base salaries of the following Named Executive Officers of Ameren Corporation (“Ameren”), Union Electric Company (“UE”) and Ameren Illinois Company (“AIC”) (which officers are employed by Ameren and/or an Ameren subsidiary as of February 16, 2023, and were determined to the extent applicable by reference to the Amere

*Revised Schedule I to Second Amended and Restated Ameren Change of Control Severance Plan, as amended

Exhibit 10.24 SCHEDULE I CHANGE OF CONTROL SEVERANCE PLAN PARTICIPANTS EFFECTIVE FEBRUARY 10, 2023 Benefit Level1 - 3 Baxter, Warner L. Lyons, Martin J. Birk, Mark C. Moehn, Michael Nwamu, Chonda * Singh, Leonard * * Not eligible for excise tax gross-up provisions (for new officers effective on or after October 1, 2009) 1 Severance benefits include: •Cash severance, defined as a multiple of i) ann

Form of Performance Share Unit Award Agreement (Relative Total Shareholder Return metric) for awards issued in 2023 pursuant to 2022 Omnibus Incentive Compensation Plan

Exhibit 10.45 2023 Performance Share Unit Award Agreement 59961003v.4 78539999v.2 Ameren Corporation 2023 Performance Share Unit Award Agreement (TSR) THIS AGREEMENT, effective as of the Grant Date set forth in the Notice of 2023 Performance Share Unit Award (TSR) ("Notice"), represents the grant of Performance Share Units by Ameren Corporation (“Ameren”), to the Participant set forth in the Notic

Subsidiaries of Ameren

Exhibit 21.1 SUBSIDIARIES OF AMEREN CORPORATION AT DECEMBER 31, 2022 Name State or Jurisdiction of Organization Ameren Corporation Missouri Ameren Development Company Missouri Missouri Central Railroad Company Delaware QST Enterprises Inc. Illinois Ameren EIP Investment, LLC Delaware Ameren Accelerator Investments, LLC Delaware AmerenEnergy Medina Valley Cogen, L.L.C. Illinois Ameren Transmission

Powers of Attorney with respect to Ameren

Exhibit 24.1 POWER OF ATTORNEY WHEREAS, AMEREN CORPORATION, a Missouri corporation (herein referred to as the "Company"), is required to file with the Securities and Exchange Commission, under the provisions of the Securities Exchange Act of 1934, as amended, its annual report on Form 10-K for the year ended December 31, 2022; and WHEREAS, each of the individuals identified below is a director of

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): February 15, 2023 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

EX-99.2 3 q42022ex992earningsrelease.htm EX-99.2 Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended December 31, Year Ended December 31, 2022 2021 2022 2021 Operating Revenues: Electric $ 1,610 $ 1,189 $ 6,581 $ 5,297 Natural gas 436 356 1,376 1,097 Total operating revenues 2,046 1,545 7,957 6,394 Operating E

Ameren Announces 2022 Results and Issues Guidance for 2023 Earnings and Long-Term Growth

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts Media Investors Tony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces 2022 Results and Issues Guidance for 2023 Earnings and Long-Term Growth •2022 Diluted Earnings Per Share (EPS) were $4.14, Compared to $3.84 in 2021 •2023 Diluted EPS G

AEE / Ameren Corp / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 13)* Name of issuer: Ameren Corp. Title of Class of Securities: Common Stock CUSIP Number: 023608102 Date of Event Which Requires Filing of this Statement: December 30, 2022 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ☒ Rule

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): January 20, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-147

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): January 6, 2023 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-1475

Amended and Restated Credit Agreement, dated as of December 6, 2022, by and among Ameren, Ameren Illinois and JP Morgan Chase Bank, N.A., as agent and the lenders party thereto

  EXHIBIT 10.2   EXECUTION VERSION       AMENDED AND RESTATED CREDIT AGREEMENT   DATED AS OF DECEMBER 6, 2022,   among   AMEREN CORPORATION and AMEREN illinois company as Borrowers,   THE LENDERS FROM TIME TO TIME PARTY HERETO   and   JPMORGAN CHASE BANK, N.A. as Administrative Agent       JPMorgan ChaSe Bank, N.A., BARCLAYS BANK PLC, MUFG Bank, LTD., BOFA SECURITIES, INC. and wells fargo SECURITI

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): December 6, 2022

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): December 6, 2022 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-147

Amended and Restated Credit Agreement, dated as of December 6, 2022, by and among Ameren, Ameren Missouri and JP Morgan Chase Bank, N.A., as agent and the lenders party thereto

  EXHIBIT 10.1   EXECUTION VERSION       AMENDED AND RESTATED CREDIT AGREEMENT   DATED AS OF DECEMBER 6, 2022,   among   AMEREN CORPORATION and UNION ELECTRIC company as Borrowers,   THE LENDERS FROM TIME TO TIME PARTY HERETO   and   JPMORGAN CHASE BANK, N.A. as Administrative Agent       JPMorgan ChaSe Bank, N.A., BARCLAYS BANK PLC, MUFG Bank, LTD., BOFA SECURITIES, INC. and wells fargo SECURITIE

Underwriting Agreement relating to the Bonds, dated November 8, 2022, between Ameren Illinois and the several underwriters named therein, for whom BofA Securities, Inc., Goldman Sachs & Co. LLC, RBC Capital Markets, LLC and TD Securities (USA) LLC are acting as representatives.

Exhibit 1.1 Ameren Illinois Company First Mortgage Bonds due 2052 Underwriting Agreement November 8, 2022 BofA Securities, Inc. Goldman Sachs & Co. LLC RBC Capital Markets, LLC TD Securities (USA) LLC As Representatives of the several Underwriters named in Schedule I to the applicable Pricing Agreement c/o BofA Securities, Inc. One Bryant Park New York, New York 10036 Goldman Sachs & Co. LLC 200 W

Supplemental Indenture, dated as of November 1, 2022, to Ameren Illinois Mortgage for 5.90% First Mortgage Bonds due 2052

Exhibit 4.2 WHEN RECORDED MAIL TO: Ameren Illinois Company Jonathan T. Shade One Ameren Plaza (MC 1310) 1901 Chouteau Avenue St. Louis, MO 63103 AMEREN ILLINOIS COMPANY (SUCCESSOR TO ILLINOIS POWER COMPANY) TO THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. AS SUCCESSOR TRUSTEE TO HARRIS TRUST AND SAVINGS BANK SUPPLEMENTAL INDENTURE DATED AS OF NOVEMBER 1, 2022 TO GENERAL MORTGAGE INDENTURE AND DE

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): November 22, 2022 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): November 8, 2022 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State of other jurisdiction of incorporation (Commission File N

Up to $1,000,199,028 Common Stock

TABLE OF CONTENTS ?Filed pursuant to Rule 424(b)(5) ?Registration No. 333-249475? PROSPECTUS SUPPLEMENT (To Prospectus dated October 14, 2020) Up to $1,000,199,028 Common Stock ? We have entered into a sales agreement with Barclays Capital Inc., BofA Securities, Inc., Goldman Sachs & Co. LLC, J.P. Morgan Securities LLC, Mizuho Securities USA LLC, Morgan Stanley & Co. LLC, MUFG Securities Americas

Calculation of Filing Fee Tables (1) Form 424(b)(5) (Form Type) Ameren Corporation (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities and Carry Forward Securities

Exhibit 107 Calculation of Filing Fee Tables (1) Form 424(b)(5) (Form Type) Ameren Corporation (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities and Carry Forward Securities Security type Security class title Fee calculation or carry forward rule Amount registered Proposed maximum offering price per unit Maximum aggregate offering price Fee rate Amount of registration fee Carry forward form type Carry forward file number Carry forward initial effective date Filing fee previously paid in connection with unsold securities to be carried forward Newly Registered Securities Fees to Be Paid Equity Ameren Corporation?s Common Stock, par value $.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended September 30, 2022 OR ? Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact nam

Ameren Announces Third Quarter 2022 Results

EX-99.1 2 q32022ex991earningsrelease.htm EX-99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces Third Quarter 2022 Results •Third Quarter Diluted Earnings Per Share were $1.74 in 2022 vs. $1.65 in 2021 •Guidance Range for 202

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): November 3, 2022 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

EX-99.2 3 q32022ex992earningsrelease.htm EX-99.2 Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended September 30, Nine Months Ended September 30, 2022 2021 2022 2021 Operating Revenues: Electric $ 2,140 $ 1,668 $ 4,971 $ 4,108 Natural gas 166 143 940 741 Total operating revenues 2,306 1,811 5,911 4,849 Operat

Underwriting Agreement relating to the Bonds, dated August 15, 2022, between Ameren Illinois and the several underwriters named therein, for whom BNY Mellon Capital Markets, LLC, Mizuho Securities USA LLC, Morgan Stanley & Co. LLC, Truist Securities, Inc. and Wells Fargo Securities, LLC are acting as representatives.

? Exhibit?1.1 ? Ameren Illinois Company ? First Mortgage Bonds due 2032 ? Underwriting Agreement ? August?15, 2022 ? BNY Mellon Capital Markets, LLC Mizuho Securities USA LLC Morgan Stanley?& Co. LLC Truist Securities,?Inc. Wells Fargo Securities, LLC ? As Representatives of the several Underwriters named in Schedule I to the applicable Pricing Agreement ? c/o BNY Mellon Capital Markets, LLC ? 240

Supplemental Indenture, dated as of August 1, 2022, to Ameren Illinois Mortgage for 3.85% First Mortgage Bonds due 2032

Exhibit 4.2 WHEN RECORDED MAIL TO: Ameren Illinois Company Jonathan T. Shade One Ameren Plaza (MC 1310) 1901 Chouteau Avenue St. Louis, MO 63103 AMEREN ILLINOIS COMPANY (SUCCESSOR TO ILLINOIS POWER COMPANY) TO THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A. AS SUCCESSOR TRUSTEE TO HARRIS TRUST AND SAVINGS BANK SUPPLEMENTAL INDENTURE DATED AS OF AUGUST 1, 2022 TO GENERAL MORTGAGE INDENTURE AND DEED

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 29, 2022 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-1475

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q ? Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the Quarterly Period Ended June 30, 2022 OR ? Transition report pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 for the transition period from to Commission File Number Exact name of

AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts)

Exhibit 99.2 AMEREN CORPORATION (AEE) CONSOLIDATED STATEMENT OF INCOME (Unaudited, in millions, except per share amounts) Three Months Ended June 30, Six Months Ended June 30, 2022 2021 2022 2021 Operating Revenues: Electric $ 1,513 $ 1,284 $ 2,831 $ 2,440 Natural gas 213 188 774 598 Total operating revenues 1,726 1,472 3,605 3,038 Operating Expenses: Fuel 83 173 259 238 Purchased power 318 129 49

Ameren Announces Second Quarter 2022 Results

Exhibit 99.1 NEWS RELEASE 1901 Chouteau Avenue: St. Louis, MO 63103: Ameren.com Contacts: Media Analysts Anthony Paraino Andrew Kirk 314.554.2182 314.554.3942 [email protected] [email protected] For Immediate Release Ameren Announces Second Quarter 2022 Results ?Second Quarter Diluted Earnings Per Share were $0.80 in 2022 vs. $0.80 in 2021 ?Guidance Range for 2022 Reaffirmed at $3.95 to $4.15 per

Results of Operations and Financial Condition, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 4, 2022 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Nu

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K

UNITED STATES SECURITIES AND EXCHANGE COMMISISION WASHINGTON, DC 20549 FORM 11-K ? ANNUAL REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 OR ? TRANSITION REPORT PURSUANT TO SECTION 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from to COMMISSION FILE NUMBER 1-14756 A.

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): June 22, 2022 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 13, 2022 AMEREN CORPORATION (Exact name of registrant as specified in its charter) Missouri 1-14756 43-1723446 (State or other jurisdiction of incorporation) (Commission File Numb

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of report (Date of earliest event reported): May 12, 2022 Commission File Number Exact Name of Registrant as Specified in Charter; State of Incorporation; Address and Telephone Number IRS Employer Identification Number 1-14756 A

2022 Omnibus Incentive Compensation Plan

Exhibit 10.1 Ameren Corporation 2022 Omnibus Incentive Compensation Plan ARTICLE 1 Establishment, Effectiveness, Purpose and Duration Section 1.01. Establishment. Ameren Corporation, a Missouri corporation (hereinafter referred to as the ?Company?), establishes an incentive compensation plan to be known as the Ameren Corporation 2022 Omnibus Incentive Compensation Plan (hereinafter referred to as

Corporation 2022 Omnibus Incentive Compensation Plan

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