How many watts does a central AC use?
Most central ACs use 2,000–5,000 watts while running (typically about 3,500 W) and 3,500–8,000 W for a few seconds when the motor or compressor starts. At the U.S. average rate of 18.16¢/kWh, a typical one costs about $50.85 a month ($610 a year, if used about 120 days a year).
Roughly 2,000–2,500 W for a 2-ton system up to 4,000–5,000 W for a 4-ton system (Champion). The compressor cycles, so real hours of running depend on the weather.
Cost to run a central AC: calculator
Running vs starting watts
Running watts are what it draws while operating; they drive your electricity bill. Starting watts are a short surge when a motor or compressor kicks on; they matter for sizing a generator or power station.
| Source | Running | Starting |
|---|---|---|
| Champion Power Equipment generator wattage chart | 2,000–5,000 W | 3,500–8,000 W |
| Honda generator wattage chart (PDF) | 2,500–6,000 W | 3,300–7,800 W |
| EcoFlow appliance wattage chart | 3,500–5,000 W | 10,500–15,000 W |
Will a power station run it?
It draws too much power to run long on a battery: a 1,000 Wh power station would last only about 15 minutes (assuming 85% conversion efficiency). Look for at least 5,000 W continuous output and 13,000 W surge (peak). That's beyond most portable power stations; a large generator or home backup system is needed. Check your power station or generator →
Cost by state
Based on 3,500 W for 8 hours a day, 120 days a year (3,360 kWh/yr).
Cost to run a central AC in every state
| State | Rate | Per month | Per year |
|---|---|---|---|
| Alabama | 16.33¢ | $45.72 | $549 |
| Alaska | 29.41¢ | $82.35 | $988 |
| Arizona | 15.05¢ | $42.14 | $506 |
| Arkansas | 14.37¢ | $40.24 | $483 |
| California | 29.75¢ | $83.30 | $1,000 |
| Colorado | 17.17¢ | $48.08 | $577 |
| Connecticut | 24.51¢ | $68.63 | $824 |
| Delaware | 18.70¢ | $52.36 | $628 |
| District of Columbia | 25.98¢ | $72.74 | $873 |
| Florida | 14.99¢ | $41.97 | $504 |
| Georgia | 15.90¢ | $44.52 | $534 |
| Hawaii | 47.18¢ | $132 | $1,585 |
| Idaho | 13.37¢ | $37.44 | $449 |
| Illinois | 19.32¢ | $54.10 | $649 |
| Indiana | 17.02¢ | $47.66 | $572 |
| Iowa | 17.06¢ | $47.77 | $573 |
| Kansas | 15.47¢ | $43.32 | $520 |
| Kentucky | 13.80¢ | $38.64 | $464 |
| Louisiana | 12.87¢ | $36.04 | $432 |
| Maine | 32.11¢ | $89.91 | $1,079 |
| Maryland | 21.40¢ | $59.92 | $719 |
| Massachusetts | 30.48¢ | $85.34 | $1,024 |
| Michigan | 22.99¢ | $64.37 | $772 |
| Minnesota | 17.20¢ | $48.16 | $578 |
| Mississippi | 14.43¢ | $40.40 | $485 |
| Missouri | 16.02¢ | $44.86 | $538 |
| Montana | 15.57¢ | $43.60 | $523 |
| Nebraska | 13.54¢ | $37.91 | $455 |
| Nevada | 12.72¢ | $35.62 | $427 |
| New Hampshire | 27.64¢ | $77.39 | $929 |
| New Jersey | 24.61¢ | $68.91 | $827 |
| New Mexico | 16.51¢ | $46.23 | $555 |
| New York | 28.65¢ | $80.22 | $963 |
| North Carolina | 14.95¢ | $41.86 | $502 |
| North Dakota | 13.31¢ | $37.27 | $447 |
| Ohio | 19.38¢ | $54.26 | $651 |
| Oklahoma | 14.82¢ | $41.50 | $498 |
| Oregon | 15.92¢ | $44.58 | $535 |
| Pennsylvania | 21.77¢ | $60.96 | $731 |
| Rhode Island | 28.18¢ | $78.90 | $947 |
| South Carolina | 15.76¢ | $44.13 | $530 |
| South Dakota | 15.15¢ | $42.42 | $509 |
| Tennessee | 13.42¢ | $37.58 | $451 |
| Texas | 15.91¢ | $44.55 | $535 |
| Utah | 13.31¢ | $37.27 | $447 |
| Vermont | 23.84¢ | $66.75 | $801 |
| Virginia | 17.64¢ | $49.39 | $593 |
| Washington | 14.63¢ | $40.96 | $492 |
| West Virginia | 16.31¢ | $45.67 | $548 |
| Wisconsin | 19.41¢ | $54.35 | $652 |
| Wyoming | 14.43¢ | $40.40 | $485 |
FAQ
How many watts does a central AC use?
Most central ACs use 2,000–5,000 watts while running (typically about 3,500 W) and 3,500–8,000 W for a few seconds when the motor or compressor starts. At the U.S. average rate of 18.16¢/kWh, a typical one costs about $50.85 a month ($610 a year, if used about 120 days a year).
What are the starting watts of a central AC?
About 3,500–8,000 W for a second or two at start-up. This matters when sizing a generator or power station, not for your electricity bill.
How much does it cost to run a central AC?
About $50.85 a month at the U.S. average rate (18.16¢/kWh, August 2026), based on 3,500 W for 8 hours a day, 120 days a year (3,360 kWh/yr). In the cheapest state it's about $35.62 a month; in the most expensive, $132.
How many kWh does a central AC use?
About 3,360 kWh a year (280 kWh a month), based on 3,500 W for 8 hours a day, 120 days a year (3,360 kWh/yr).
Can a power station or generator run a central AC?
It draws too much power to run long on a battery: a 1,000 Wh power station would last only about 15 minutes. Look for at least 5,000 W continuous output and 13,000 W surge (peak). That's beyond most portable power stations; a large generator or home backup system is needed.