Filed Pursuant to Rule 433

Registration No. 333-249475-02

Ameren Illinois Company

Pricing Term Sheet

November 9, 2020

Issue:	1.55% First Mortgage Bonds due 2030
Principal Amount:	$375,000,000
Coupon (Interest Rate):	1.55% per annum
Maturity Date:	November 15, 2030
Benchmark Treasury:	0.625% due August 15, 2030
Benchmark Treasury Price:	97-00+
Benchmark Treasury Yield:	0.946%
Spread to Benchmark Treasury:	+65 basis points
Re-offer Yield:	1.596%
Offering Price (Issue Price):	99.577% of the principal amount
Interest Payment Dates:	May 15 and November 15, commencing May 15, 2021
Optional Redemption:	Prior to August 15, 2030 (the “Par Call Date”), at any time at the greater of (1) 100% of the principal amount or (2) the sum of the present values of the remaining scheduled payments of principal and interest that would be payable on any First Mortgage Bonds to be redeemed if such First Mortgage Bonds matured on the Par Call Date discounted at the Adjusted Treasury Rate plus 10 basis points, in each case plus accrued and unpaid interest, and on or after the Par Call Date, at any time at 100% of the principal amount plus accrued and unpaid interest.
Expected Ratings (Moody’s/S&P)*:	A1 (stable) / A (stable)
Trade Date:	November 9, 2020
Settlement Date:	November 23, 2020 (T+9)**
CUSIP / ISIN:	02361D AV2 / US02361DAV29

Joint Book-Running Managers:	Mizuho Securities USA LLC
	SMBC Nikko Securities America, Inc.
	Truist Securities, Inc.
Co-Managers:	Bancroft Capital, LLC
	Blaylock Van, LLC
	Cabrera Capital Markets, LLC
	Loop Capital Markets LLC

The term “Adjusted Treasury Rate” has the meaning ascribed to that term in the Issuer’s Preliminary Prospectus Supplement, dated November 9, 2020.

*   A security rating is not a recommendation to buy, sell or hold securities and should be evaluated independently of any other rating.  The rating is subject to revision or withdrawal at any time by the assigning rating organization.

** The Issuer expects to deliver the First Mortgage Bonds against payment for the First Mortgage Bonds on or about the Settlement Date specified above, which will be the ninth business day following the date hereof. Under Rule 15c6-1 under the Securities Exchange Act of 1934, as amended, trades in the secondary market generally are required to settle in two business days, unless the parties to a trade expressly agree otherwise. Accordingly, purchasers who wish to trade the First Mortgage Bonds more than two business days prior to the scheduled settlement date will be required, by virtue of the fact that the First Mortgage Bonds initially are expected to settle in T+9, to specify an alternative settlement arrangement at the time of any such trade to prevent a failed settlement.

The Issuer has filed a registration statement (including a prospectus) with the SEC for the offering to which this communication relates.  Before you invest, you should read the prospectus in that registration statement and other documents the Issuer has filed with the SEC for more complete information about the Issuer and this offering.  You may get these documents for free by visiting EDGAR on the SEC’s website at www.sec.gov.  Alternatively, the Issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by calling Mizuho Securities USA LLC toll-free at 1-866-271-7403, SMBC Nikko Securities America, Inc. toll-free at 1-888-868-6856 or Truist Securities, Inc. toll-free at 1-800-685-4786.

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