Ameren Corporation (Ameren) is the parent holding company of:
• Ameren Illinois, based in Collinsville, Illinois, and
• Ameren Missouri, based in St. Louis, Missouri
Ameren was incorporated in Missouri on Aug. 7, 1995. On Dec. 31, 1997, CIPSCO
Incorporated and Union Electric combined. In 2003, Ameren grew with the
acquisition of CILCORP Inc., parent of Central Illinois Light Company, and in
2004, Ameren acquired Illinois Power Company from Dynegy Inc.
Ameren employees, totaling approximately 8,500, provide energy services to
approximately 2.4 million electric customers and 900,000 natural gas
customers across 64,000 square miles in Illinois and Missouri.