How much does it cost to run a window air conditioner in Illinois?
A 900-watt window air conditioner costs about $0.17 an hour in Illinois, or about $41.52 a month at 8 hours a day.
Illinois electricity averages 19.22¢ per kWh, about 6% more than the U.S. average of 18.19¢. It ranks 36 of 51 from cheapest to most expensive.
Your cost
Cost by wattage
| Wattage | Hour | Day | Month | Year |
|---|---|---|---|---|
| Low (500 W) | $0.10 | $0.77 | $23.06 | $281 |
| Typical (900 W) | $0.17 | $1.38 | $41.52 | $505 |
| High (1,500 W) | $0.29 | $2.31 | $69.19 | $842 |
Day, month and year assume 8 hours of use a day.
Other cooling costs
| Appliance | Typical | Per month |
|---|---|---|
| Central air conditioner | 3,500 W | $161 |
| Ceiling fan | 50 W | $2.31 |
Ways to spend less
- Each degree warmer on the thermostat trims cooling cost.
- A ceiling fan lets you set the AC a few degrees higher and feel the same.
Monthly cost in every state
| State | Rate | Per month |
|---|---|---|
| North Dakota | 12.36¢ | $26.70 |
| Nebraska | 12.90¢ | $27.86 |
| Idaho | 12.96¢ | $27.99 |
| Utah | 13.16¢ | $28.43 |
| Louisiana | 13.35¢ | $28.84 |
| Nevada | 13.53¢ | $29.22 |
| Oklahoma | 13.58¢ | $29.33 |
| Arkansas | 13.61¢ | $29.40 |
| Tennessee | 13.87¢ | $29.96 |
| Montana | 13.95¢ | $30.13 |
| Wyoming | 13.95¢ | $30.13 |
| Missouri | 13.96¢ | $30.15 |
| Iowa | 14.20¢ | $30.67 |
| Kentucky | 14.27¢ | $30.82 |
| Washington | 14.40¢ | $31.10 |
| South Dakota | 14.50¢ | $31.32 |
| North Carolina | 14.94¢ | $32.27 |
| New Mexico | 15.08¢ | $32.57 |
| Mississippi | 15.19¢ | $32.81 |
| Kansas | 15.21¢ | $32.85 |
| Florida | 15.30¢ | $33.05 |
| Georgia | 15.40¢ | $33.26 |
| Oregon | 15.40¢ | $33.26 |
| Arizona | 15.44¢ | $33.35 |
| West Virginia | 15.47¢ | $33.42 |
| South Carolina | 15.93¢ | $34.41 |
| Texas | 16.06¢ | $34.69 |
| Minnesota | 16.25¢ | $35.10 |
| Alabama | 16.54¢ | $35.73 |
| Colorado | 16.72¢ | $36.12 |
| Virginia | 16.83¢ | $36.35 |
| Indiana | 17.04¢ | $36.81 |
| Delaware | 17.86¢ | $38.58 |
| Ohio | 18.70¢ | $40.39 |
| Wisconsin | 19.00¢ | $41.04 |
| Illinois | 19.22¢ | $41.52 |
| Pennsylvania | 21.04¢ | $45.45 |
| Maryland | 21.30¢ | $46.01 |
| Michigan | 21.53¢ | $46.50 |
| Vermont | 23.95¢ | $51.73 |
| New Jersey | 23.98¢ | $51.80 |
| District of Columbia | 24.66¢ | $53.27 |
| New Hampshire | 26.79¢ | $57.87 |
| Alaska | 27.09¢ | $58.51 |
| Connecticut | 27.97¢ | $60.42 |
| Rhode Island | 29.22¢ | $63.12 |
| New York | 29.38¢ | $63.46 |
| Maine | 29.99¢ | $64.78 |
| Massachusetts | 30.14¢ | $65.10 |
| California | 33.25¢ | $71.82 |
| Hawaii | 46.28¢ | $99.96 |
At 900 watts for 8 hours a day, 30 days a month. Rates are average residential prices from the U.S. Energy Information Administration, January–July 2026 (EIA Electric Power Monthly). Your bill's rate may differ, so enter your own in the calculator.