United States Cooling and fans
How much does it cost to run a window air conditioner?
A window air conditioner draws 500 to 1,500 watts depending on its cooling capacity. A 5,000 BTU unit for a small bedroom sits near 500 watts, a 12,000 BTU unit for a living room near 1,100.
A 900 watt window air conditioner costs about 11 cents an hour to run in the US on average at 18.16 cents per kWh. Running it 8 hours a day cycling 70% of the time comes to about 92 cents a day, $27.86 a month and $334.30 a year.
- Prices: EIA, August 2026, every state
- Wattage range with its source
- Checked 26 October 2026
Uses 5.0 kWh a day, 153 kWh a month, at 18.16 cents per kWh (US average).
The dial places the daily cost between a 50 watt fan and a 4.5 kW water heater on 2.5 hours a day.
A 900 watt window air conditioner costs about 11 cents an hour to run in the US on average at 18.16 cents per kWh. Running it 8 hours a day cycling 70% of the time comes to about 92 cents a day, $27.86 a month and $334.30 a year.
What this assumes
The default is a 900 watt window air conditioner running 8 hours a day, drawing full power 70% of the time it is switched on (the rest of the time a thermostat or sensor has it idle). Published typical ratings run from 500 to 1,500 watts. Your label or manual gives the exact figure, and the calculator takes it.
The price is the average residential rate in each state from the EIA's Electric Power Monthly for August 2026, released 23 October 2026. The next monthly table is due 24 November 2026. A fixed tariff, a time-of-use plan or a different payment method changes the rate, which is why the rate field is editable.
Cost to run a window air conditioner in every state
Same 900 watt window air conditioner, 8 hours a day, priced at each state's average residential rate for August 2026. Cheapest: Nevada at 12.72 cents per kWh. Dearest: Hawaii at 47.18. Change the numbers above and the table follows.
| State | Rate | Per hour | Per day | Per month | Per year |
|---|---|---|---|---|---|
| Nevada | 12.72c | 8 cents | 64 cents | $19.51 | $234.16 |
| Louisiana | 12.87c | 8.1 cents | 65 cents | $19.74 | $236.92 |
| North Dakota | 13.31c | 8.4 cents | 67 cents | $20.42 | $245.02 |
| Utah | 13.31c | 8.4 cents | 67 cents | $20.42 | $245.02 |
| Idaho | 13.37c | 8.4 cents | 67 cents | $20.51 | $246.12 |
| Tennessee | 13.42c | 8.5 cents | 68 cents | $20.59 | $247.04 |
| Nebraska | 13.54c | 8.5 cents | 68 cents | $20.77 | $249.25 |
| Kentucky | 13.8c | 8.7 cents | 70 cents | $21.17 | $254.04 |
| Arkansas | 14.37c | 9.1 cents | 72 cents | $22.04 | $264.53 |
| Mississippi | 14.43c | 9.1 cents | 73 cents | $22.14 | $265.64 |
| Wyoming | 14.43c | 9.1 cents | 73 cents | $22.14 | $265.64 |
| Washington | 14.63c | 9.2 cents | 74 cents | $22.44 | $269.32 |
| Oklahoma | 14.82c | 9.3 cents | 75 cents | $22.73 | $272.82 |
| North Carolina | 14.95c | 9.4 cents | 75 cents | $22.93 | $275.21 |
| Florida | 14.99c | 9.4 cents | 76 cents | $23.00 | $275.94 |
| Arizona | 15.05c | 9.5 cents | 76 cents | $23.09 | $277.05 |
| South Dakota | 15.15c | 9.5 cents | 76 cents | $23.24 | $278.89 |
| Kansas | 15.47c | 9.7 cents | 78 cents | $23.73 | $284.78 |
| Montana | 15.57c | 9.8 cents | 78 cents | $23.89 | $286.62 |
| South Carolina | 15.76c | 9.9 cents | 79 cents | $24.18 | $290.12 |
| Georgia | 15.9c | 10 cents | 80 cents | $24.39 | $292.70 |
| Texas | 15.91c | 10 cents | 80 cents | $24.41 | $292.88 |
| Oregon | 15.92c | 10 cents | 80 cents | $24.42 | $293.06 |
| Missouri | 16.02c | 10 cents | 81 cents | $24.58 | $294.91 |
| West Virginia | 16.31c | 10 cents | 82 cents | $25.02 | $300.24 |
| Alabama | 16.33c | 10 cents | 82 cents | $25.05 | $300.61 |
| New Mexico | 16.51c | 10 cents | 83 cents | $25.33 | $303.93 |
| Indiana | 17.02c | 11 cents | 86 cents | $26.11 | $313.31 |
| Iowa | 17.06c | 11 cents | 86 cents | $26.17 | $314.05 |
| Colorado | 17.17c | 11 cents | 87 cents | $26.34 | $316.08 |
| Minnesota | 17.2c | 11 cents | 87 cents | $26.39 | $316.63 |
| Virginia | 17.64c | 11 cents | 89 cents | $27.06 | $324.73 |
| Delaware | 18.7c | 12 cents | 94 cents | $28.69 | $344.24 |
| Illinois | 19.32c | 12 cents | 97 cents | $29.64 | $355.65 |
| Ohio | 19.38c | 12 cents | 98 cents | $29.73 | $356.76 |
| Wisconsin | 19.41c | 12 cents | 98 cents | $29.78 | $357.31 |
| Maryland | 21.4c | 13 cents | $1.08 | $32.83 | $393.94 |
| Pennsylvania | 21.77c | 14 cents | $1.10 | $33.40 | $400.76 |
| Michigan | 22.99c | 14 cents | $1.16 | $35.27 | $423.21 |
| Vermont | 23.84c | 15 cents | $1.20 | $36.57 | $438.86 |
| Connecticut | 24.51c | 15 cents | $1.24 | $37.60 | $451.19 |
| New Jersey | 24.61c | 16 cents | $1.24 | $37.75 | $453.04 |
| District of Columbia | 25.98c | 16 cents | $1.31 | $39.85 | $478.26 |
| New Hampshire | 27.64c | 17 cents | $1.39 | $42.40 | $508.81 |
| Rhode Island | 28.18c | 18 cents | $1.42 | $43.23 | $518.75 |
| New York | 28.65c | 18 cents | $1.44 | $43.95 | $527.41 |
| Alaska | 29.41c | 19 cents | $1.48 | $45.12 | $541.40 |
| California | 29.75c | 19 cents | $1.50 | $45.64 | $547.66 |
| Massachusetts | 30.48c | 19 cents | $1.54 | $46.76 | $561.09 |
| Maine | 32.11c | 20 cents | $1.62 | $49.26 | $591.10 |
| Hawaii | 47.18c | 30 cents | $2.38 | $72.38 | $868.52 |
Rates: EIA Electric Power Monthly, Table 5.6.A, residential sector, August 2026, preliminary. All rates with the year-on-year change.
How a window air conditioner uses electricity
The compressor cycles on the thermostat. In a room that is well shaded and not too big it runs perhaps 70% of the time, which is the duty used here. On a 95 degree afternoon in a sunny room it may never switch off.
The efficiency rating (CEER) on the yellow EnergyGuide label tells you watts per BTU. A unit with a CEER of 12 uses about 20% less than one with a CEER of 10 for the same cooling.
Ways to cut the cost
- Match the BTU rating to the room. An oversized unit short-cycles and does not dehumidify well.
- Shade the window and seal the gaps around the unit.
- Clean the filter every two weeks in summer.
Questions people ask
How much does a window AC cost per month?
A 900 watt unit at 70% duty for 8 hours a day uses about 150 kWh a month. At 18 cents that is about 27 dollars. Running it 24 hours a day triples that.
Is a window unit cheaper than central air?
For one room, yes. Central air cools the whole house at 2,500 to 5,000 watts. If you only need one cool room, a window unit costs a fraction of that.
Other cooling and fans costs
More in the US
Sources
The electricity price on this page is read from the data file that also lists the release it came from. The wattage range is a published typical range, not a measurement of your appliance.