How much does it cost to run a window air conditioner?
A window air conditioner drawing 1,000 watts, used 8 hours a day, uses about 8.00 kWh per day and costs about $1.55 per day, $47.27 per month, and $566.77 per year at the US average residential rate of 19.4¢/kWh. Enter your own wattage, hours, and state below for an exact figure.
Estimates only — based on typical wattages and average state rates, not your actual bill.
What drives the cost
Window units draw roughly 500-1,800 watts depending on capacity (BTU) and efficiency. Because they cool one room rather than a whole house, they often cost far less to run than central air — provided you're not running several at once. Like central systems, the compressor cycles with the thermostat, so real consumption is below nameplate.
Cost at different daily usage
Same window air conditioner at 1,000 watts, run for different amounts of time, at 19.4¢/kWh.
| Usage | kWh/day | Per day | Per month | Per year |
|---|---|---|---|---|
| 4 h/day | 4.00 kWh | $0.78 | $23.63 | $283.39 |
| 8 h/day | 8.00 kWh | $1.55 | $47.27 | $566.77 |
| 12 h/day | 12.00 kWh | $2.33 | $70.90 | $850.16 |
| 16 h/day | 16.00 kWh | $3.11 | $94.53 | $1,133.54 |
Cost by model power draw
Not all models are equal. At 8 h/day, here is what the range costs.
| Model | Power | kWh/day | Per day | Per month |
|---|---|---|---|---|
| Low-draw model | 500 W | 4.00 kWh | $0.78 | $23.63 |
| Typical | 1,000 W | 8.00 kWh | $1.55 | $47.27 |
| High-draw model | 1,800 W | 14.40 kWh | $2.80 | $85.08 |
Cost by state
A window air conditioner at 1,000 W for 8 h/day, priced at each state's average residential rate.
| State | Rate | Per day | Per month | Per year |
|---|---|---|---|---|
| Alabama | 16.8¢ | $1.34 | $40.84 | $489.68 |
| Alaska | 28.2¢ | $2.26 | $68.75 | $824.32 |
| Arizona | 15.2¢ | $1.22 | $37.09 | $444.72 |
| Arkansas | 14.4¢ | $1.15 | $34.97 | $419.31 |
| California | 33.2¢ | $2.66 | $80.97 | $970.90 |
| Colorado | 16.2¢ | $1.29 | $39.35 | $471.87 |
| Connecticut | 27.4¢ | $2.19 | $66.65 | $799.20 |
| Delaware | 19.4¢ | $1.55 | $47.19 | $565.90 |
| District of Columbia | 25.4¢ | $2.03 | $61.85 | $741.68 |
| Florida | 15.2¢ | $1.21 | $36.94 | $442.96 |
| Georgia | 15.8¢ | $1.27 | $38.57 | $462.53 |
| Hawaii | 52.0¢ | $4.16 | $126.63 | $1,518.40 |
| Idaho | 12.3¢ | $0.99 | $30.07 | $360.62 |
| Illinois | 23.9¢ | $1.91 | $58.08 | $696.42 |
| Indiana | 18.1¢ | $1.45 | $44.20 | $529.98 |
| Iowa | 14.1¢ | $1.13 | $34.43 | $412.89 |
| Kansas | 15.1¢ | $1.21 | $36.84 | $441.80 |
| Kentucky | 15.0¢ | $1.20 | $36.48 | $437.42 |
| Louisiana | 14.2¢ | $1.13 | $34.46 | $413.18 |
| Maine | 28.6¢ | $2.29 | $69.72 | $836.00 |
| Maryland | 21.8¢ | $1.74 | $53.01 | $635.68 |
| Massachusetts | 28.8¢ | $2.31 | $70.18 | $841.54 |
| Michigan | 22.0¢ | $1.76 | $53.60 | $642.69 |
| Minnesota | 16.9¢ | $1.36 | $41.28 | $494.94 |
| Mississippi | 16.2¢ | $1.29 | $39.35 | $471.87 |
| Missouri | 13.7¢ | $1.09 | $33.31 | $399.46 |
| Montana | 14.7¢ | $1.17 | $35.72 | $428.36 |
| Nebraska | 13.6¢ | $1.09 | $33.09 | $396.83 |
| Nevada | 13.6¢ | $1.09 | $33.12 | $397.12 |
| New Hampshire | 27.3¢ | $2.19 | $66.55 | $798.04 |
| New Jersey | 23.3¢ | $1.86 | $56.67 | $679.48 |
| New Mexico | 14.1¢ | $1.13 | $34.39 | $412.30 |
| New York | 29.9¢ | $2.39 | $72.89 | $873.96 |
| North Carolina | 15.1¢ | $1.21 | $36.75 | $440.63 |
| North Dakota | 13.6¢ | $1.09 | $33.14 | $397.41 |
| Ohio | 19.5¢ | $1.56 | $47.54 | $569.98 |
| Oklahoma | 13.4¢ | $1.07 | $32.58 | $390.70 |
| Oregon | 16.3¢ | $1.30 | $39.62 | $475.08 |
| Pennsylvania | 21.6¢ | $1.72 | $52.48 | $629.26 |
| Rhode Island | 29.5¢ | $2.36 | $71.74 | $860.23 |
| South Carolina | 16.2¢ | $1.29 | $39.40 | $472.46 |
| South Dakota | 15.7¢ | $1.26 | $38.31 | $459.32 |
| Tennessee | 14.5¢ | $1.16 | $35.24 | $422.52 |
| Texas | 16.4¢ | $1.32 | $40.03 | $480.05 |
| Utah | 13.0¢ | $1.04 | $31.56 | $378.43 |
| Vermont | 24.9¢ | $1.99 | $60.61 | $726.79 |
| Virginia | 17.6¢ | $1.41 | $42.88 | $514.21 |
| Washington | 14.9¢ | $1.20 | $36.41 | $436.54 |
| West Virginia | 16.8¢ | $1.34 | $40.91 | $490.56 |
| Wisconsin | 19.7¢ | $1.58 | $48.07 | $576.41 |
| Wyoming | 14.8¢ | $1.18 | $36.04 | $432.16 |
How to cut the cost
- Size the unit to the room; an oversized AC short-cycles, cooling poorly and dehumidifying badly.
- Seal the window gaps around the unit — leaked warm air makes it run longer.
- Clean or replace the filter monthly during the cooling season.
- Use the energy-saver or eco mode so the fan cycles with the compressor instead of running constantly.
Compare with related appliances
Monthly cost at typical usage and 19.4¢/kWh.
Questions
Is a window AC cheaper than central air?
Per unit, yes — a single window AC typically uses a fraction of what central air does. The comparison flips if you run several window units to cool the whole house.
How do you calculate what a window air conditioner costs to run?
Multiply its wattage by the hours it runs per day, divide by 1,000 to get kilowatt-hours, then multiply by your electricity rate. For a window air conditioner: 1,000 W × 8 h ÷ 1,000 = 8.00 kWh per day, which at 19.4¢/kWh is $1.55 per day.
How many watts does a window air conditioner use?
Typically 1,000 watts, with most models falling between 500 and 1,800 watts. The label on the appliance or its power supply gives the figure for your specific unit.