Company: AILIM
Filing Date: 2025-09-16
Form Type: 424B2
Source: 0001104659-25-090464
Chunk: 4

Company: Ameren Illinois Co
Filing Date: 2025-09-16
Form: 424B2
Chunk 4
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, we file annual, quarterly and current reports, information statements and other information with the SEC. The SEC maintains a website at www.sec.gov that contains reports, proxy and information statements and other information regarding companies, such as us, that file documents with the SEC electronically. The documents can be found by searching the EDGAR archives of the SEC electronically.

The SEC allows us to “incorporate by reference” the information that we file with the SEC, which means that we can disclose important information to you by referring you to those documents. The information incorporated by reference is considered to be part of this prospectus supplement and the accompanying prospectus and you should read it with the same care. Later information that we file with the SEC will automatically update and supersede this information and will be deemed to be incorporated by reference into this prospectus supplement and the accompanying prospectus (other than any documents, or portions of documents, not deemed to be filed). We incorporate by reference into this prospectus supplement and the accompanying prospectus the following documents previously filed with the SEC:

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our 2024 Form 10-K;

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our Quarterly Reports on Form 10-Q for the quarters ended March 31, 2025, and June 30, 2025; and

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our Current Reports on Form 8-K filed with the SEC on March 3, 2025, and May 12, 2025.

We are also incorporating by reference all additional documents that we file with the SEC under Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act after the date of this prospectus supplement until the offering contemplated by this prospectus supplement is completed or terminated.

Any statement contained in this prospectus supplement or the accompanying prospectus, or in a document incorporated or deemed to be incorporated by reference in this prospectus supplement or the accompanying prospectus, will be deemed to be modified or superseded for purposes of this prospectus supplement and the accompanying prospectus to the extent that a statement contained in this prospectus supplement, or in any separately filed document which also is or is deemed to be incorporated by reference herein, modifies or supersedes that statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute part of this prospectus supplement or the accompanying prospectus.

You may request a free copy of these filings by writing or telephoning us, c/o Ameren Corporation, at the following address:

Ameren Illinois Company 
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