Cost to Run a Window Air Conditioner in Illinois
Illinois's average residential electricity rate is 20.5¢/kWh as of April 2026 — the 36th cheapest in the country, 9% above the U.S. average. At typical usage (8 hours/day), a window air conditioner here costs $44.87 per month.
Per hour
$0.18
at 500–1,500 W
Per day
$1.48
8 hours/day
Per month
$44.87
219 kWh
Per year
$539
2,628 kWh
By usage level in Illinois
| Usage | Per day | Per month | Per year |
|---|---|---|---|
| Light (4 hrs/day) | $0.74 | $22.44 | $269 |
| Typical (8 hrs/day) | $1.48 | $44.87 | $539 |
| Heavy (16 hrs/day) | $2.95 | $89.74 | $1,077 |
Illinois vs. the rest of the country
Monthly cost at typical usage.
Frequently asked questions
How much does it cost to run a window air conditioner in Illinois?
At Illinois's current average residential rate of 20.5¢/kWh (April 2026), a window air conditioner with typical usage costs about $1.48 per day, $44.87 per month, or $539 per year.
Is running a window air conditioner in Illinois more expensive than average?
Yes. Illinois's electricity costs about 9% more than the U.S. average, so the same usage costs $44.87 per month here versus $41.15 nationally.
What does electricity cost in Illinois right now?
Illinois residents pay an average of 20.5¢ per kWh as of April 2026 — the 36th cheapest rate of the 51 U.S. jurisdictions we track.