Stock Power Instructions

Instructions: You may use the Stock Power form to transfer ownership of your Ameren Corporation common stock, Union Electric Company preferred stock and Central Illinois Public Service Company preferred stock.

1. Fill out this on-line form and press the create button.

2. Print the resulting screen. A copy of these instructions will print along with your newly created form.

3. Take the printed form to a member of the Medallion Guarantee program, such as a broker, bank, or credit union. Each owner must have their signature Medallion Guaranteed.

4. The stock certificate and any other transfer requirements should be:

Mailed To: Ameren Services Company Investor Services P.O. Box 66887 St. Louis, MO 63166-6887

Delivered To: Ameren Services Company Investor Services One Ameren Plaza 1901 Chouteau Avenue St. Louis, MO 63103

If mailing, we recommend registered mail, insured for 2% of the market value of the shares.