Ameren shareholders approve board, pay and auditor

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-Ok

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the
Securities Exchange Act of 1934

Date of report (Date of earliest occasion reported):
May 14, 2026

Check the suitable field under if the Form 8-Ok submitting is meant to concurrently fulfill the submitting obligation of the registrants underneath any of the next provisions:

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

¨ Requesting materials pursuant to Rule 14a-12 underneath the Exchange Act (17 CFR 240.14a-12)

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

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

Securities registered pursuant to Section 12(b) of the Act:

Indicate by verify mark whether or not the registrant is an rising development firm as outlined 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).

If an rising development firm, point out by verify mark if the registrant has elected to not use the prolonged transition interval for complying with any new or revised monetary accounting requirements supplied pursuant to Section 13(a) of the Exchange Act.

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

At the annual assembly of shareholders of every of Ameren Corporation (“Ameren”), Union Electric Company, doing enterprise as Ameren Missouri (“Ameren Missouri”), and Ameren Illinois Company, doing enterprise as Ameren Illinois (“Ameren Illinois”), held on May 14, 2026 (“Annual Meeting”), the issues listed under have been submitted to a vote of every firm’s respective shareholders.

Ameren

Item (1): Election of Directors

The following people (comprising Ameren’s full Board of Directors) have been elected:

Item (2): Advisory Approval of Executive Compensation

Item (3): Ratification of the Appointment of PricewaterhouseCoopers LLP as Independent Registered Public Accounting Firm for the Fiscal Year Ending December 31, 2026

Ameren Missouri

Item (1): Election of Directors

At Ameren Missouri’s Annual Meeting, the next people (comprising Ameren Missouri’s full Board of Directors) have been elected: Michael L. Moehn, Ajay Ok. Arora, David M. Feinberg, Ryan J. Martin, and Leonard P. Singh. Each particular person acquired 102,123,834 votes for election and no withheld votes, abstentions or dealer non-votes.

Ameren Illinois

Item (1): Election of Directors

At Ameren Illinois’ Annual Meeting, the next people (comprising Ameren Illinois’ full Board of Directors) have been elected: Patrick E. Smith Sr., David M. Feinberg, Michael L. Moehn, Theresa A. Shaw, and Leonard P. Singh. Each particular person acquired 25,452,373 votes for election and no withheld votes, abstentions or dealer non-votes.

This mixed Form 8-Ok is being filed individually by Ameren Corporation, Union Electric Company and Ameren Illinois Company (every a “registrant”). Information contained herein regarding any particular person registrant has been filed by such registrant by itself behalf. No registrant makes any illustration as to info regarding some other registrant.

SIGNATURES

Pursuant to the necessities of the Securities Exchange Act of 1934, every registrant has duly induced this report back to be signed on its behalf by the undersigned thereunto duly approved. The signature for every undersigned firm shall be deemed to narrate solely to issues having reference to such firm or its subsidiaries.

Date: May 18, 2026