Material Event Form 8 K

On June 27, 2024, Ameren Illinois Company ("Ameren Illinois"), a subsidiary of Ameren Corporation, sold $625 million principal amount of its 5.55% First Mortgage Bonds due 2054 (the "Bonds"). The Bonds were offered pursuant to a Registration Statement on Form S-3 (File No. 333-274977-01), which became effective on October 13, 2023, and a Prospectus Supplement dated June 17, 2024, to a Prospectus dated October 13, 2023. Ameren Illinois received net offering proceeds of approximately $618.3 million, before expenses, upon closing of the transaction.

This Current Report on Form 8-K is being filed to report as exhibits certain documents in connection with the offering of the Bonds.