Form 8-K

8-K — AMEREN CORP

Accession: 0001104659-26-063184

Filed: 2026-05-18

Period: 2026-05-14

CIK: 0001002910

SIC: 4931 (ELECTRIC & OTHER SERVICES COMBINED)

Item: Submission of Matters to a Vote of Security Holders

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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 14, 2026

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

(Missouri

Corporation)

1901

Chouteau Avenue

St.

Louis, Missouri

63103

(314)

621-3222

43-1723446

1-2967

Union Electric

Company

(Missouri Corporation)

1901 Chouteau Avenue

St. Louis, Missouri 63103

(314) 621-3222

43-0559760

1-3672

Ameren Illinois Company

(Illinois Corporation)

10 Richard Mark Way

Collinsville, Illinois 62234

(618)

343-8150

37-0211380

Check

the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrants

under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered

pursuant to Section 12(b) of the Act:

Title

of each class

Trading

Symbol(s)

Name

of each exchange

on which registered

Common

Stock, $0.01 par value per

AEE

New

York Stock Exchange

Indicate by check mark whether the registrant

is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2

of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging Growth Company

Ameren Corporation

Union Electric Company

Ameren Illinois Company

an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying

with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.

Ameren Corporation

Union Electric Company

Ameren Illinois Company

Co-Registrant

CIK

0000100826

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ITEM 5.07 Submission of Matters to a Vote of Security Holders.

At the annual meeting of shareholders of each of Ameren Corporation

(“Ameren”), Union Electric Company, doing business as Ameren Missouri (“Ameren Missouri”), and Ameren Illinois

Company, doing business as Ameren Illinois (“Ameren Illinois”), held on May 14, 2026 (“Annual Meeting”),

the matters listed below were submitted to a vote of each company’s respective shareholders.

Ameren

Item (1): Election of Directors

The following individuals (comprising Ameren’s full Board of

Directors) were elected:

Name

Votes For

Votes Against

Abstentions

Broker Non-Votes

Cynthia J. Brinkley

211,811,213

6,224,999

509,328

24,519,860

Ward H. Dickson

215,897,083

2,148,175

500,282

24,519,860

Jamie L. Engstrom

216,191,429

1,854,870

499,241

24,519,860

Ellen M. Fitzsimmons

210,790,937

7,306,393

448,210

24,519,860

Rafael Flores

212,466,281

5,556,585

522,674

24,519,860

Richard J. Harshman

211,458,704

6,517,496

569,340

24,519,860

Craig S. Ivey

213,177,307

4,882,181

486,052

24,519,860

Steven H. Lipstein

203,929,254

14,096,981

519,305

24,519,860

Martin J. Lyons, Jr.

211,634,204

6,520,326

391,010

24,519,860

Leo S. Mackay, Jr.

215,933,079

2,121,870

490,591

24,519,860

Timothy S. Rausch

215,974,758

1,948,882

621,900

24,519,860

Steven O. Vondran

215,831,571

2,064,068

649,901

24,519,860

Item (2): Advisory Approval of Executive Compensation

Vote Result

Votes For

Votes Against

Abstentions

Broker Non-Votes

Approved

208,210,735

9,383,298

951,507

24,519,860

Item (3): Ratification of the Appointment of PricewaterhouseCoopers

LLP as Independent Registered Public Accounting Firm for the Fiscal Year Ending December 31, 2026

Vote Result

Votes For

Votes Against

Abstentions

Broker Non-Votes

Approved

232,732,466

9,840,141

492,793

—

Ameren Missouri

Item (1): Election of Directors

At Ameren Missouri’s Annual Meeting, the following individuals

(comprising Ameren Missouri’s full Board of Directors) were elected: Michael L. Moehn, Ajay K. Arora, David M. Feinberg, Ryan J.

Martin, and Leonard P. Singh. Each individual received 102,123,834 votes for election and no withheld votes, abstentions or broker non-votes.

Ameren Illinois

Item (1): Election of Directors

At Ameren Illinois’ Annual Meeting, the following individuals

(comprising Ameren Illinois’ full Board of Directors) were elected: Patrick E. Smith Sr., David M. Feinberg, Michael L. Moehn, Theresa

A. Shaw, and Leonard P. Singh. Each individual received 25,452,373 votes for election and no withheld votes, abstentions or broker non-votes.

This combined Form 8-K is being filed separately by Ameren Corporation,

Union Electric Company and Ameren Illinois Company (each a “registrant”). Information contained herein relating to any individual

registrant has been filed by such registrant on its own behalf. No registrant makes any representation as to information relating to any

other registrant.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934,

each registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. The signature for

each undersigned company shall be deemed to relate only to matters having reference to such company or its subsidiaries.

AMEREN CORPORATION

(Registrant)

By:

/s/ David M. Feinberg

Name:

David M. Feinberg

Title:

Executive Vice President, General Counsel and Secretary

UNION ELECTRIC COMPANY

(Registrant)

By:

/s/ David M. Feinberg

Name:

David M. Feinberg

Title:

Executive Vice President, General Counsel and Secretary

AMEREN ILLINOIS COMPANY

(Registrant)

By:

/s/ David M. Feinberg

Name:

David M. Feinberg

Title:

Executive Vice President, General Counsel and Secretary

Date: May 18, 2026

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May 14, 2026

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