EIA data · IL
Illinois: what each way of heating costs
The short answer
In Illinois, electricity averaged 18.91¢/kWh (0.9¢ above the US average). That puts mini-split heat at about $19 per million BTU at rated efficiency, versus $12 for natural gas. A heat pump loses on fuel cost at rated efficiency, and loses at 5°F.
Fuel prices are EIA SEDS 2024 residential averages per million BTU of fuel, divided by 90% furnace/boiler efficiency. Electricity is the EIA trailing-twelve-month residential average. Heat pump efficiency: ENERGY STAR median cold-climate system, HSPF2 10 (COP 2.93) rated, COP 2 at 5°F.
Cities in Illinois
| City | 99% design temp | Heat pump $/yr | Gas $/yr | Oil $/yr | Propane $/yr |
|---|---|---|---|---|---|
| Chicago | 4°F | $1,197 | $649 | $1,468 | $1,217 |
| Springfield | 7°F | $1,090 | $597 | $1,351 | $1,120 |
Keep going
- Cost-to-heat calculator: put in a ZIP for your own number instead of a state average.
- All city estimates, sizing by design temperature and incentives.
- States with a similar electricity price: Wisconsin, Ohio, Pennsylvania, Colorado.
Questions people ask
What is the electricity price in Illinois?
EIA reports a residential average of 18.91¢/kWh for Illinois over September 2025 to August 2026; the latest month, August 2026, was 19.32¢/kWh. The US average over the same twelve months was 18.04¢/kWh.
Is a heat pump cheaper than natural gas in Illinois?
Per million BTU of delivered heat, a heat pump at its rated HSPF2 costs about $19 versus $12 for natural gas at 90% efficiency. At 5°F, when efficiency is lowest, the heat pump costs about $28 per million BTU.