Ameren Illinois Company, a regulated utility and wholly owned subsidiary of Ameren Corporation (NYSE: AEE), has priced a new offering of $350 million aggregate principal amount in first mortgage bonds due 2055. These bonds will pay a 5.625% annual coupon and were issued at a premium of 103.196%, translating into a re-offer yield of 5.405%. The bonds represent a further issuance of Ameren Illinois' original 2055 series, which was first floated in March 2025. The offering is scheduled to close on September 26, 2025, subject to standard conditions, and the proceeds will be used to repay short-term debt.