Cost to heat a home in Illinois
Cheapest to run in Illinois is
a gas furnace
A gas furnace costs about $848 a year less than a heat pump here. Cheap gas relative to electricity is the reason, and no amount of equipment efficiency closes that gap at these prices.
A heating season compared
| Gas furnacecheapest80% AFUE | $1655 |
| Heat pumpHSPF2 8.5 | $2503 |
| Electric resistanceBaseboard or furnace | $6236 |
At 23.85¢ a kilowatt hour and $1.48 a therm, for a 1,800 square foot home over 5,900 heating degree days.
About the cold
Illinois sees about 130 freezing nights a year. That is enough that a heat pump needs to be a cold-climate model, and backup heat will run on the worst nights — which is already reflected in the figures above.
Common questions
Is a heat pump cheaper than gas heating in Illinois?
No. At Illinois's prices a gas furnace costs about $1655 a season against $2503 for a heat pump, so switching would raise running costs by roughly $848 a year. Cheap gas, not poor equipment, is the reason.
What does it cost to heat a house in Illinois for a winter?
Between about $1655 and $6236 for a 1,800 square foot home, depending entirely on the system. Illinois runs around 5,900 heating degree days a year.
Why is electric resistance heat so much more expensive?
It converts electricity to heat one for one, while a heat pump moves heat rather than making it and delivers two to three times as much per unit of electricity. In Illinois that difference is about $3733 a season.
Work it out for your home
These assume a 1,800 square foot home and typical equipment. The calculator takes your ZIP code, your floor area and your actual furnace efficiency, and includes what switching would cost to install.
Prices from the US Energy Information Administration, residential sector, 2026-05. Heating load estimated from Illinois's heating degree days. An estimate, not a bill — insulation, air sealing, ductwork and thermostat habits all move it, and no calculator can see those.