Billowatt

Cost to Run a Window Air Conditioner in Illinois

Illinois's average residential electricity rate is 23.9¢/kWh as of May 2026 — the 40th cheapest in the country, 30% above the U.S. average. At typical usage (8 hours/day), a window air conditioner here costs $52.31 per month.

Per hour

$0.22

at 500–1,500 W

Per day

$1.72

8 hours/day

Per month

$52.31

219 kWh

Per year

$628

2,628 kWh

By usage level in Illinois

Usage Per day Per month Per year
Light (4 hrs/day) $0.86 $26.16 $314
Typical (8 hrs/day) $1.72 $52.31 $628
Heavy (16 hrs/day) $3.44 $105 $1,256

Illinois vs. the rest of the country

Monthly cost at typical usage.

Illinois $52.31
Midwest average $37.59
U.S. average $40.27

Frequently asked questions

How much does it cost to run a window air conditioner in Illinois?

At Illinois's current average residential rate of 23.9¢/kWh (May 2026), a window air conditioner with typical usage costs about $1.72 per day, $52.31 per month, or $628 per year.

Is running a window air conditioner in Illinois more expensive than average?

Yes. Illinois's electricity costs about 30% more than the U.S. average, so the same usage costs $52.31 per month here versus $40.27 nationally.

What does electricity cost in Illinois right now?

Illinois residents pay an average of 23.9¢ per kWh as of May 2026 — the 40th cheapest rate of the 51 U.S. jurisdictions we track.

Window Air Conditioner costs in nearby states

What else costs to run in Illinois

See the full Illinois electricity cost guide →