Central Air Conditioner running cost, by state
A central air conditioner drawing 3500W costs about $1,218 a year at the US average electricity rate — but that average hides a fourfold spread. Pick your state for a real figure.
At the US average rate
3500W at a 65% duty cycle, 8 hours a day, at 18.34¢/kWh.
About this appliance
Central AC draws between 2,000 and 5,000 watts depending on tonnage, but a correctly sized unit cycles rather than running flat out. A thermostat set 1 degree lower can raise seasonal cost noticeably, because the compressor duty cycle rises even though the wattage does not.
- Nameplate wattage is not running cost. This central air conditioner draws about 3500W when active, but cycles roughly 65% of the time it is switched on, so effective consumption is near 2275W.
- At typical use this is a major load - around 6,643 kWh a year. Efficiency upgrades here pay back faster than on any small appliance.
- Models vary widely, from about 2000W to 5000W. Check the nameplate on your own unit rather than assuming an average, because the spread is more than 2x.
- Insulation and air sealing reduce runtime, which lowers cost more reliably than adjusting the thermostat by a degree.
- If your utility offers time-of-use pricing, shifting this load off-peak can cut its cost substantially without using any less energy.
Annual cost in every state
Sorted cheapest first. Click any state for the full calculation with that state’s rate loaded.
| State | Rate /kWh | Per month | Per year | Relative |
|---|---|---|---|---|
| Nevada | 13.11¢ | $72.63 | $871 | |
| Nebraska | 13.25¢ | $73.41 | $880 | |
| Utah | 13.37¢ | $74.07 | $888 | |
| Louisiana | 13.49¢ | $74.74 | $896 | |
| Tennessee | 14.07¢ | $77.95 | $935 | |
| Arkansas | 14.12¢ | $78.23 | $938 | |
| North Dakota | 14.12¢ | $78.23 | $938 | |
| Kentucky | 14.26¢ | $79.00 | $947 | |
| Oklahoma | 14.33¢ | $79.39 | $952 | |
| Idaho | 14.37¢ | $79.61 | $955 | |
| North Carolina | 14.74¢ | $81.66 | $979 | |
| Mississippi | 14.88¢ | $82.44 | $988 | |
| Washington | 14.91¢ | $82.60 | $990 | |
| New Mexico | 15.06¢ | $83.43 | $1,000 | |
| Florida | 15.10¢ | $83.66 | $1,003 | |
| Montana | 15.14¢ | $83.88 | $1,006 | |
| Arizona | 15.18¢ | $84.10 | $1,008 | |
| Wyoming | 15.24¢ | $84.43 | $1,012 | |
| South Dakota | 15.36¢ | $85.10 | $1,020 | |
| West Virginia | 15.45¢ | $85.59 | $1,026 | |
| South Carolina | 15.55¢ | $86.15 | $1,033 | |
| Kansas | 15.71¢ | $87.03 | $1,044 | |
| Iowa | 15.93¢ | $88.25 | $1,058 | |
| Texas | 15.94¢ | $88.31 | $1,059 | |
| Missouri | 16.22¢ | $89.86 | $1,077 | |
| Oregon | 16.32¢ | $90.41 | $1,084 | |
| Georgia | 16.36¢ | $90.64 | $1,087 | |
| Alabama | 16.40¢ | $90.86 | $1,089 | |
| Colorado | 17.13¢ | $94.90 | $1,138 | |
| Virginia | 17.22¢ | $95.40 | $1,144 | |
| Indiana | 17.51¢ | $97.01 | $1,163 | |
| Minnesota | 17.52¢ | $97.06 | $1,164 | |
| Ohio | 19.19¢ | $106 | $1,275 | |
| Delaware | 19.29¢ | $107 | $1,281 | |
| Wisconsin | 19.56¢ | $108 | $1,299 | |
| Illinois | 19.89¢ | $110 | $1,321 | |
| Pennsylvania | 21.73¢ | $120 | $1,444 | |
| Maryland | 21.84¢ | $121 | $1,451 | |
| Michigan | 22.99¢ | $127 | $1,527 | |
| Connecticut | 24.32¢ | $135 | $1,616 | |
| District of Columbia | 24.39¢ | $135 | $1,620 | |
| Vermont | 24.44¢ | $135 | $1,624 | |
| New Jersey | 24.95¢ | $138 | $1,657 | |
| New Hampshire | 27.01¢ | $150 | $1,794 | |
| Alaska | 28.21¢ | $156 | $1,874 | |
| Rhode Island | 29.23¢ | $162 | $1,942 | |
| New York | 29.49¢ | $163 | $1,959 | |
| Maine | 29.59¢ | $164 | $1,966 | |
| Massachusetts | 29.61¢ | $164 | $1,967 | |
| California | 34.74¢ | $192 | $2,308 | |
| Hawaii | 52.72¢ | $292 | $3,502 |
Common questions
How many watts does a central air conditioner use?
A typical central air conditioner draws about 3500 watts while running, with most models falling between 2000W and 5000W. Check the nameplate label or manual for your specific unit - the range is wide enough that averages can mislead.
How much electricity does a central air conditioner use per day?
At around 8 hours of use a day and a 65% duty cycle, that works out to roughly 18.2 kWh per day, or about 546 kWh a month. Your actual figure depends on your usage and model.
Why does the cost differ so much between states?
Residential electricity rates across the US range from about 12.35 cents per kWh in North Dakota to 46.62 cents in Hawaii - nearly a fourfold difference. The same central air conditioner, used identically, therefore costs almost four times as much to run in the most expensive state as in the cheapest.
Is it cheaper to run a central air conditioner at night?
Only if you are on a time-of-use or variable tariff. On a flat rate, the time of day makes no difference to cost. If you are on time-of-use pricing, off-peak hours are typically materially cheaper, and shifting this load can reduce its cost without reducing usage.