Company: AILIM
Filing Date: 2025-09-16
Form Type: 424B2
Source: 0001104659-25-090464
Chunk: 19

Company: Ameren Illinois Co
Filing Date: 2025-09-16
Form: 424B2
Chunk 19
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 as a domestic trust for U.S. federal income tax purposes.

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TABLE OF CONTENTS

Qualified Reopening

We intend to treat the bonds offered hereby as being issued in a “qualified reopening” of our 5.625% First Mortgage Bonds due 2055 issued on March 3, 2025. For U.S. federal income tax purposes, debt instruments issued in a qualified reopening are deemed to be part of the same issue as the original debt instruments. Under the treatment described in this paragraph, for U.S. federal income tax purposes, the bonds offered hereby will be treated as having the same issue date and same issue price as our 5.625% First Mortgage Bonds due 2055 issued on March 3, 2025. The remainder of this discussion assumes the correctness of the treatment described in this paragraph.

Stated Interest

Generally, and subject to the discussions of “Pre-Issuance Accrued Interest” and “Amortizable Bond Premium” below, stated interest on a bond will be includible in your gross income and taxable as ordinary income for U.S. federal income tax purposes at the time such interest is received or accrued in accordance with your regular method of tax accounting.

Pre-Issuance Accrued Interest

The price to the public for the bonds offered hereby will reflect interest accrued from September 1, 2025 to the date the bonds are issued (“pre-issuance accrued interest”). The payment of pre-issuance accrued interest on the bonds will be treated as a non-taxable return of the pre-issuance accrued interest, rather than as an amount includible in a U.S. holder’s income, and should be excluded from a U.S. holder’s adjusted tax basis in a bond. Prospective purchasers of the bonds are urged to consult their own tax advisors regarding pre-issuance accrued interest.

Amortizable Bond Premium

If you acquire a bond for an amount that is greater than its principal amount (excluding amounts attributable to pre-issuance accrued interest), then you will be considered to have acquired the bond with “amortizable bond premium.” In general, the amount of amortizable bond premium with respect to any bond will be equal in amount to the excess, if any, of the U.S. holder’s purchase price for the bond (excluding amounts attributable to accrued interest) over the principal amount of the bond.

A U.S. holder may elect to amortize bond