The following table presents the principal credit ratings of the Ameren companies by Moody's and S&P effective as of May 31, 2017.

Issuer Moody's
Standard and Poor's

Rating Outlook
Rating Outlook
Ameren Corporation
Issuer/Corp. Credit Rating Baa1 stable
BBB+ stable
Senior Unsecured Baa1 stable
BBB stable
Commercial Paper P-2 stable
A-2 stable
Ameren Missouri:
FMB/Senior Secured A2 stable
A stable
Issuer/Corp. Credit Rating Baa1 stable
BBB+ stable
Senior Unsecured Baa1 stable
BBB+ stable
Preferred Stock Baa3 stable
BBB- stable
Commercial Paper P-2 stable
A-2 stable
Insured Tax Exempts - 92&98 A,B,C A2 stable
A stable
Ameren Illinois Company:




FMB/Senior Secured A1 stable
A stable
Issuer/Corp. Credit Rating A3 stable
BBB+ stable
Senior Unsecured A3 stable
BBB+ stable
Preferred Stock Baa2 stable
BBB- stable
Commercial Paper P-2 stable
A-2 stable
Issuer
Ameren Corporation
Issuer/Corp. Credit Rating
Moody's
Rating
Outlook
Baa1
stable
Standard & Poor's
Rating
Outlook
BBB+
stable
Senior Unsecured
Moody's
Rating
Outlook
Baa1
stable
Standard & Poor's
Rating
Outlook
BBB
stable
Commercial Paper
Moody's
Rating
Outlook
P-2
stable
Standard & Poor's
Rating
Outlook
A-2
stable
Ameren Missouri:
FMB/Senior Secured
Moody's
Rating
Outlook
A2
stable
Standard & Poor's
Rating
Outlook
A
stable
Issuer/Corp. Credit Rating
Moody's
Rating
Outlook
Baa1
stable
Standard & Poor's
Rating
Outlook
BBB+
stable
Senior Unsecured
Moody's
Rating
Outlook
Baa1
stable
Standard & Poor's
Rating
Outlook
BBB+
stable
Preferred Stock
Moody's
Rating
Outlook
Baa3
stable
Standard & Poor's
Rating
Outlook
BBB-
stable
Commercial Paper
Moody's
Rating
Outlook
P-2
stable
Standard & Poor's
Rating
Outlook
A-2
stable
Insured Tax Exempts - 92&89 A,B,C
Moody's
Rating
Outlook
A2
stable
Standard & Poor's
Rating
Outlook
A
stable
Ameren Illinois Company:
FMB/Senior Secured
Moody's
Rating
Outlook
A1
stable
Standard & Poor's
Rating
Outlook
A
stable
Issuer/Corp. Credit Rating
Moody's
Rating
Outlook
A3
stable
Standard & Poor's
Rating
Outlook
BBB+
stable
Senior Unsecured
Moody's
Rating
Outlook
A3
stable
Standard & Poor's
Rating
Outlook
BBB+
stable
Preferred Stock
Moody's
Rating
Outlook
Baa2
stable
Standard & Poor's
Rating
Outlook
BBB-
stable
Commercial Paper
Moody's
Rating
Outlook
P-2
stable
Standard & Poor's
Rating
Outlook
A-2
stable

A credit rating is not a recommendation to buy, sell, or hold securities. It should be evaluated independently of any other rating. Ratings are subject to revision or withdrawal at any time by the rating organization.