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Commonwealth Edison (ComEd) vs Ameren Illinois Company: who pays less in Illinois?

Data as of: EIA-861 annual 2024 (released 2025) · EIA monthly state prices February 2026 · EIA weekly heating-fuel survey Mar 30, 2026 · retail-choice registry reviewed Jun 2026 · URDB tariffs pulled Jun 2026. Page generated 2026-06-12.

Commonwealth Edison (ComEd) and Ameren Illinois Company customers paid essentially the same in 2024: 15.22¢/kWh versus 15.26¢/kWh (EIA-861) — a dead heat, under $5 per year apart at typical usage (10,800 kWh/yr). Their territories meet in 7 IL counties (Bureau, Ford, Kendall, …). You cannot switch wires companies — the territory is set by your address, though in Illinois both utilities' customers can shop the supply portion of the bill.

Side by side (IL, EIA-861)

Commonwealth Edison (ComEd) vs Ameren Illinois Company — residential averages from federal EIA-861 filings
MetricCommonwealth Edison (ComEd)Ameren Illinois Company
2024 average price, ¢/kWh15.2215.26
2023 average price, ¢/kWh14.7817.04
Annual cost at 10,800 kWh, $/yr$1,643$1,648
Residential customers (2024)2,922,223520,498
OwnershipInvestor-ownedInvestor-owned
Counties served in IL2481

Average price = residential revenue ÷ sales (bundled service): the all-in price customers actually paid, including supply, delivery and riders. Profiles: Commonwealth Edison (ComEd) · Ameren Illinois Company · Illinois overview.

Where the territories meet

Both utilities file EIA-861 service territory in: Bureau · Ford · Kendall · LaSalle · Livingston · Marshall · Woodford counties (IL, 2024).

Adjoining or overlapping territory in a county does not mean households there can pick between the two — service maps are parcel-level and fixed. The county overlap mainly matters when choosing where to live or comparing town-level costs.

Can you actually choose between them?

No — not for delivery. Distribution territories are exclusive and set by address; Commonwealth Edison (ComEd) and Ameren Illinois Company do not compete for the same meters. Illinois does have retail supply choice: customers of either utility may buy the supply portion from a licensed third-party supplier, or stay on the utility's default supply rate. An offer only saves money if it beats your utility's price to compare (printed on the bill); compare offers at pluginillinois.org. The price gap above mainly matters when choosing where to live, comparing towns, or benchmarking your bill.

Questions people ask

Is Commonwealth Edison (ComEd) cheaper than Ameren Illinois Company?
They were effectively tied in 2024: Commonwealth Edison (ComEd) averaged 15.22 cents/kWh and Ameren Illinois Company 15.26 (EIA-861) — less than $5 per year apart at 10,800 kWh.
Can I switch from Ameren Illinois Company to Commonwealth Edison (ComEd)?
No — distribution territories are exclusive and set by address; you cannot pick between the two wires companies. Illinois does allow supply choice: either utility's customers can shop the supply portion at pluginillinois.org if an offer beats the utility's price to compare.
About these numbers. Rates shown are averages computed from federal regulatory filings (EIA Form 861) and public tariff databases — confirm with your utility before making decisions; your actual rate depends on your tariff, usage, and riders. Distribution utility is determined by address and generally cannot be chosen; in retail-choice states you may choose your supplier for the supply portion of the bill. Savings figures use 10,800 kWh/yr (US average residential usage) and are estimates, not quotes. EnergySavings is an independent data project by CertiHomes and is not affiliated with any utility, supplier, or government agency.