The secured debt settled with net proceeds of roughly $492 million and runs through Ameren Missouri’s nearly century-old mortgage indenture.

June 30, 2026

Union Electric Company, the regulated Missouri utility doing business as Ameren Missouri, completed a $500 million sale of 5.75% first mortgage bonds maturing in 2056, adding to the long-dated secured debt that anchors its capital structure. The Ameren Corporation subsidiary closed the transaction on June 29, 2026, taking in net proceeds of about $492.2 million before expenses.

Terms and syndicate

The bonds were sold off a shelf registration that became effective in October 2023, with terms set under a prospectus supplement dated June 15, 2026. Fifth Third Securities, Mizuho Securities USA, TD Securities (USA), Truist Securities and U.S. Bancorp Investments acted as representatives for the underwriting syndicate.

A long-standing mortgage framework

The new series sits within Ameren Missouri’s first mortgage indenture, a financing framework originating in 1937 and administered by The Bank of New York Mellon as successor trustee, with a supplemental indenture dated June 1, 2026 governing the issue. As secured obligations backed by a lien on utility property, first mortgage bonds remain the lowest-cost long-term funding instrument available to operators of this type, which is why regulated utilities lean on them so heavily for multi-decade financing.

The offering was reported jointly by Ameren Corporation and Union Electric, with each registrant filing on its own behalf and disclaiming responsibility for information relating to the other. Legality opinions were provided by Ameren Missouri’s general counsel and by outside counsel Morgan, Lewis & Bockius.