Ameren Corporation is a St. Louis-based “Fortune 500” energy company that is the parent of utility companies that serve approximately 2.4 million electric and 900,000 natural gas customers in a territory encompassing 64,000 square miles in Illinois and Missouri. Ameren was created in December 1997 through a merger of CIPSCO, Inc. and Union Electric Company. In Illinois, the three Ameren utility companies – AmerenCILCO, AmerenCIPS, AmerenIP – merged into a single public utility – Ameren Illinois Company – on October 1, 2010.
Ameren Illinois Rate Zone 1 (formerly AmerenCIPS) provides electric and natural gas services in a territory covering 20,500 square miles which encompasses 70 central and southern Illinois counties. There are nearly 400,000 retail electricity customers in 576 communities and about 190,000 retail natural gas customers in 270 communities. Among the major cities in Rate Zone 1 are Alton, Quincy, Carbondale, East St. Louis, Effingham, Mattoon and Macomb.
Ameren Illinois Rate Zone 2 (formerly AmerenCILCO) covers an area of 4,660 square miles encompassing 19 counties. There are about 210,000 retail electricity customers and approximately 216,000 retail natural gas customers. Among the major cities in Rate Zone 2 are Peoria, Springfield, Pekin, East Peoria and Lincoln.
Ameren Illinois Rate Zone 3 (formerly AmerenIP) encompasses a 15,000-square-mile territory across northern, central and southern Illinois. There are about 626,000 retail electricity customers in 313 communities and 421,000 retail natural gas customers in 258 communities. Among the major cities in Rate Zone 3 are Decatur, Champaign, Urbana, Bloomington, Danville, Belleville and Galesburg.