Ameren Illinois is being told to reduce its distribution rates for next year for its electricity customers.
The Illinois Commerce Commission this week ordered a reduction of $45 million beginning January 1.
Beth Bosch, ICC spokesperson, said the rate cut was needed because Ameren "over-collected" on its previous rates.
Ameren is still reviewing the ruling. The company initially proposed lowering its delivery rate by $30 million, then amended the figure to $37 million.
Ameren Illinois has about 1.2 million electricity customers in central and southern Illinois.
It also has about 800,000 natural gas customers. The ICC is scheduled to meet next week to discuss the rates Ameren charges for that service.