Ameren Illinois Bill Explained: Charges & Shopping Suppliers
Ameren Illinois delivers electricity across central and southern Illinois but, under the state's deregulated market, doesn't have to be your supplier. Your bill splits into delivery charges (regulated by the Illinois Commerce Commission, unaffected by supplier choice) and a supply charge — either Ameren's own Price to Compare rate or a competitive Alternative Retail Electric Supplier (ARES) rate you or your municipality chose. Businesses can shop an ARES directly through the state's Plug In Illinois comparison tool.
Delivery vs. supply on an Ameren Illinois bill
Ameren Illinois owns and maintains the distribution lines, transformers, and meters across its service territory and keeps that role no matter who supplies the actual electricity. That delivery charge — sometimes broken out further into distribution and transmission components — is the same regardless of supplier. The supply charge is the part Illinois's 1997 retail choice law opened to competition: it can come from Ameren's own default Price to Compare rate or from a competitive Alternative Retail Electric Supplier (ARES) a customer selects.
What the Price to Compare tells you
Ameren Illinois publishes a Price to Compare — a combined per-kWh figure for its electric supply charge and transmission service charge — on Plug In Illinois, the Illinois Commerce Commission's official shopping site. It exists so customers have a fair benchmark: any ARES offer should be judged against the Price to Compare, not against the full bill, since delivery charges apply no matter which supplier is chosen. The rate resets periodically as Ameren re-procures its default supply.
Municipal aggregation: an option in some Ameren communities
In parts of Illinois, including some communities in Ameren's territory, cities and counties can negotiate a group electricity supply contract on behalf of residents and small businesses through municipal aggregation, using combined buying power to try to secure a better rate than an individual customer might get alone. Most run as opt-out programs — residents are enrolled automatically unless they decline — though not every community offers one, and municipal aggregation contracts typically cover residential and small commercial accounts rather than larger business customers, who generally shop individually instead.
What this means for a business
Commercial and industrial customers in Ameren Illinois's territory can shop an ARES directly on Plug In Illinois, separately from any municipal aggregation contract that might apply to smaller accounts in the same town. Business supply contracts typically fall under different rate classes than residential ones, often with usage-based pricing tiers or demand-related components once a business crosses certain size thresholds. Before signing, comparing a supplier's quoted commercial rate against Ameren's current Price to Compare — and checking contract length, whether the rate is fixed or variable, and any early termination terms — is worth doing the way it would be for any competitive energy contract.
Frequently asked questions
Does Ameren Illinois still deliver my electricity if I switch suppliers?
Yes. Ameren Illinois owns and maintains the poles, wires, and meters in its territory and continues to handle outages and delivery no matter which company supplies your electricity — switching a supplier only changes the supply charge on your bill.
What is Ameren Illinois's Price to Compare?
The Price to Compare is the combined per-kWh rate for Ameren Illinois's electric supply charge and transmission service charge — what a customer pays if they stay on Ameren's default supply. It's published on Plug In Illinois specifically so customers can measure a competitive supplier's offer against it.
Can a business shop for its own electric supplier in Ameren Illinois's territory?
Yes. Commercial and industrial customers in Ameren Illinois's territory can shop Alternative Retail Electric Suppliers (ARES) individually, separate from any municipal aggregation program that may cover residential accounts in the same town, using the Illinois Commerce Commission's Plug In Illinois site to compare current offers.
See this on your own bill
Upload your Ameren Illinois bill and Certo reads it for you — a free bill health score, a plain-English breakdown, and whether your current supply rate is competitive.
Running a business on Ameren Illinois service?
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