Electric companies in Illinois
| Company | Homes served | Avg. bill / month | Avg. rate | Bill covers |
|---|---|---|---|---|
| ComEd | 3,727,675 | $89 | 15.2¢ | Default service |
| Ameren Illinois | 1,060,894 | $130 | 15.3¢ | Default service |
| MidAmerican Energy | 73,582 | $71 | 10.0¢ | Default service |
| City Water, Light & Power (CWLP) | 59,621 | $99 | 12.0¢ | Full bill |
| Naperville Electric Utility | 56,117 | $99 | 13.0¢ | Full bill |
You can choose your electricity supplier in Illinois
Your local utility still delivers the power and fixes the lines, but you can buy the electricity itself from a competing supplier. Where a bill above says “default service”, it covers households that stayed on the utility’s own supply.
How we calculated this
Figures come from the U.S. Energy Information Administration, Form EIA-861 (2024 data), for companies with 50,000 or more residential customers. The average bill is residential revenue divided by customers and 12 months; the rate is revenue divided by kilowatt-hours sold. Your own bill depends on your usage, plan and season. More sections for Illinois (rent, gas and more) are added as each data set goes live.
Source: U.S. EIA, Form EIA-861. Last verified November 2026.