Air Conditioner cost calculator
Find it on the label.
Use the price from your bill if you know it.
Cost to run this device
Cost = watts divided by 1,000, times hours, times your price per kWh. It covers energy only, not the cost of buying the device.
Typical draw
3,500 W
Range 500 to 5,000 W
Hours a day
8
Assumed day of use
Energy a month
851 kWh
28.0 kWh a day
Cost a month
$147
At 17.23 cents per kWh
What an air conditioner costs to run
| Period | Energy | Cost |
|---|---|---|
| One hour of running | 3.50 kWh | $0.60 |
| One day (8 hours) | 28.00 kWh | $4.83 |
| One month (30.4 days) | 851 kWh | $147 |
| One year (4 months of use) | 3,405 kWh | $587 |
Source: Planning watts of 3,500 and 8 hours a day, hours of compressor running time on a hot day. Price: 17.23 cents per kWh, the 2025 US residential average from EIA Form EIA-861.
The monthly cost is 97% of the $150.68 average US electric bill. Because it runs only about 4 months a year, the yearly cost is 4 times the monthly figure, not twelve.
Three real-life cases
One figure cannot fit every home. These three cases show how much the answer moves with the equipment and the hours.
| Case | Watts | Hours a day | kWh a month | Cost a month |
|---|---|---|---|---|
| Window unit in one bedroom | 700 | 8 | 170 | $29 |
| Central system, mild summer | 3,500 | 5 | 532 | $92 |
| Central system, hot summer | 3,500 | 12 | 1,277 | $220 |
The lowest case costs $29 a month and the highest $220. Use the calculator above to match your own.
What it costs in other states
The same air conditioner costs different amounts depending on the state, because the price per kWh differs. Here are the three cheapest states, the US average and the three costliest, for the same 851 kWh a month.
| Place | Cents per kWh | Cost a month |
|---|---|---|
| North Dakota | 11.82 | $101 |
| Idaho | 11.83 | $101 |
| Nebraska | 12.05 | $103 |
| United States average | 17.23 | $147 |
| Hawaii | 40.40 | $344 |
| California | 31.35 | $267 |
| Massachusetts | 30.41 | $259 |
Source: U.S. Energy Information Administration, Form EIA-861 (final 2025 data). Price is residential revenue divided by sales and includes fixed charges.
See electricity rates in every state to find your own.
How an air conditioner uses electricity
An air conditioner spends most of its electricity on the compressor, with a smaller share for the fans. The compressor cycles on until the thermostat is satisfied, so hours of running time are what you pay for, not hours the system is set to on.
Type and size matter most. A window unit draws under 1,000 watts, while a central system can draw 3,000 to 5,000 watts when the compressor runs. Climate, insulation, thermostat setting and the age of the system change how many hours it runs.
For scale, the EIA Residential Energy Consumption Survey found the average US home used about 171 kWh a month on air conditioning in 2020, and the average detached house about 209 kWh. These averages include homes with no such equipment, so a home that has it uses more.
The range for this kind of appliance runs from about 500 to 5,000 watts. At 8 hours a day that is $21 to $210 a month, which is why checking the label on yours is worth the minute.
Ways to cut the cost of an air conditioner
- Raise the thermostat a few degrees and use a schedule when nobody is home.
- Replace dirty filters and keep outdoor units clear of leaves and grass.
- Seal ducts and shade west-facing windows to cut running time.
Next step: Central air conditioner costs. For general ideas, read how to lower your electric bill.
Other appliances in the cooling group: Window Air Conditioner, Central Air Conditioner, Portable Air Conditioner, Ceiling Fan, Mini-Split Heat Pump, Whole-House Fan.
How we got these numbers
The cost is watts divided by 1,000, times hours, times your price per kWh. The 3,500 watts is a planning figure for this kind of appliance, set from typical product ratings, and the 8 hours is an assumed day of use. Neither is copied from a federal table. Federal guidance describes the method and warns that real wattage varies, so we publish our own typical ranges and label them as such. Prices come from EIA Form EIA-861 for 2025.
The calculation is the standard one used in the U.S. Department of Energy's consumer guidance on estimating appliance energy use. Wattage varies by product age and features, so the label on your own appliance beats any average. Read more in our methodology.
Air Conditioner cost questions
Is it cheaper to leave the air conditioner on all day or turn it off?
For most homes it is cheaper to let the temperature drift up while nobody is home and cool it again later. A smaller setback of a few degrees keeps the recovery time short. Homes with heavy humidity or a slow system may see less benefit.
Why is my summer bill so much higher than my winter bill?
Cooling is a large part of summer electricity in hot states. The EIA Residential Energy Consumption Survey ranks air conditioning among the biggest electric end uses in a typical home, and in the South it is often the largest.
How much does an air conditioner cost to run per hour?
At 3,500 watts and the 2025 US average price of 17.23 cents per kWh, about $0.60 an hour. Use your own price to get your own figure.
How many kWh does an air conditioner use in a month?
About 851 kWh for 8 hours of use a day over 30.4 days at 3,500 watts. A different wattage or schedule changes the total in proportion.