Issuer:		Central Illinois Public Service Company d/b/a AmerenCIPS
Ratings:		A3/A-
Issue:		Senior Secured Notes due 2036
Offering Size:		$61,500,000
Coupon:		6.700% per annum, payable semi-annually on each June 15^th and December 15^th, commencing December 15^th, 2006
Trade Date:		June 8^th, 2006
Settlement Date:		June 14^th, 2006
Maturity:		June 15^th, 2036
Treasury Benchmark:		5.375% due February 15^th, 2031
US Treasury Spot:		103-07
US Treasury Yield:		5.143%
Spread to Treasury:		160 basis points
Re-offer Yield:		6.743%
Price to Public (Issue Price):		99.449%
Gross Proceeds:		$61,161,135
Underwriting Discount:		0.875%
Net Proceeds:		$60,623,010
Optional Redemption:		Make Whole call, at any time at a discount rate of Treasury plus 30 bps
Minimum Denomination:		$1,000 × $1,000
Bookrunners:		Citigroup, Goldman, Sachs & Co.

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 Web site 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 Goldman, Sachs & Co. toll-free at 1-866-471-2526 or Citigroup Global Markets Inc. toll-free at 1-877-858-5407.