Energy costs in Illinois
Every figure we hold for Illinois, on one page. Each links to the working behind it.
A heating state
Illinois runs about 5,900 heating degree days against 1,100 cooling ones, so the heating system does most of the work and is where an upgrade pays off. Its electricity bill peaks in July.
Electricity
23.85¢
per kWh
Gas $1.48/therm ›
Typical bill
$132
a month
Peaks at $184 ›
Air conditioning
$266
a year
$0.50 an hour ›
Heating
$1655
a season
Gas furnace is cheaper ›
Solar payback
6.2 yrs
on a 6 kW system
Generates at 6.6¢/kWh ›
Common questions
How much does energy cost in Illinois?
Electricity is 23.85¢ per kilowatt hour and natural gas $1.48 per therm. A typical household pays about $132 a month for electricity.
Does Illinois spend more on heating or cooling?
Heating. Illinois runs about 5,900 heating degree days against 1,100 cooling ones, so winter dominates and the heating system is where money is worth spending.
For your own home
Everything above describes a 1,800 square foot home at Illinois average prices. The calculators take your ZIP code and your own numbers.
Open the calculatorsPrices from the US Energy Information Administration, 2026-05. Solar production modelled by NREL. Heating and cooling loads estimated from Illinois's degree days. Estimates, not quotes.