How much does it cost to run a box fan?
Short answer: A box fan drawing 75 watts costs about $0.01 per hour at the U.S. average residential price of 18.31¢ per kWh. Used 8 hours a day, 30 days a month, that is about $3.30 per month and $39.55 per year. In Louisiana, the cheapest state, the same use costs $2.29 a month; in Hawaii, the most expensive, $8.64.
Box fan cost calculator
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Hours per day the fan is running.
Uses 18.0 kWh per month. The starting price is the U.S. residential average; choose your state or type the price from your own bill.
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| Appliance | Usage | Per month | Remove |
|---|---|---|---|
| Total | |||
| Per year |
A 20-inch box fan draws about 75 watts on high, roughly a twelfth of what a window air conditioner uses. Running one all night costs a few cents.
Cost by size and setting
Costs below use the U.S. average price and 8 hours a day, 30 days a month.
| Type | Power | Per hour | Per month |
|---|---|---|---|
| Desk or tower fan | 40 W | $0.01 | $1.76 |
| 20-inch box fan, low | 50 W | $0.01 | $2.20 |
| 20-inch box fan, high | 75 W | $0.01 | $3.30 |
| Large pedestal fan | 100 W | $0.02 | $4.39 |
Fans cool people, not rooms
A fan does not lower the air temperature. It moves air across your skin, which makes you feel cooler. That means a fan running in an empty room is wasted electricity, however little it uses.
Using a fan with air conditioning
The U.S. Department of Energy notes that a ceiling fan lets you raise the thermostat setting by about 4°F with no reduction in comfort, and a portable fan aimed at where you are sitting works on the same principle. Since air conditioning costs ten times as much to run, that trade is strongly in your favor. On cool evenings, a box fan in a window pulling in outside air can replace the air conditioner entirely.
How to lower the cost
- Turn it off when you leave the room.
- Use the lowest speed that keeps you comfortable.
- At night, place it in a window to bring in cooler outdoor air.
- Dust the blades and grille; a clean fan moves more air.
How a box fan compares with other appliances
Typical power and use for each appliance, at the U.S. average price of 18.31¢ per kWh. Follow a link for that appliance's own calculator, or compare two side by side.
| Appliance | Power | Typical use | Energy per month | Cost per month |
|---|---|---|---|---|
| Box fan | 75 W | 8 hours a day, 30 days a month | 18.0 kWh | $3.30 |
| Ceiling fan | 50 W | 12 hours a day, 30 days a month | 18.0 kWh | $3.30 |
| Window air conditioner | 900 W | 8 hours a day, 30 days a month | 216.0 kWh | $39.55 |
| Portable air conditioner | 1,200 W | 8 hours a day, 30 days a month | 288.0 kWh | $52.73 |
| Air purifier | 50 W | 24 hours a day, 30 days a month | 36.0 kWh | $6.59 |
The math behind the numbers
75 watts ÷ 1,000 = 0.075 kW. 0.075 kW × 8 hours = 0.6 kWh per day. 0.6 kWh × $0.1831 = $0.11 per day. Over 30 days that is 18.0 kWh and $3.30 a month.
Your own figure will differ if your appliance has a different wattage, if you use it more or less, or if your price per kWh is not the national average. Change any of those in the calculator at the top of this page. Our step-by-step guide explains where to find each number.
Cost to run a box fan in every state
Based on 75 watts for 8 hours a day, 30 days a month, at each state's average residential electricity price for July 2026.
| State | Price per kWh | Per hour | Per month | Per year |
|---|---|---|---|---|
| Alabama | 16.40¢ | $0.01 | $2.95 | $35.42 |
| Alaska | 28.83¢ | $0.02 | $5.19 | $62.27 |
| Arizona | 15.38¢ | $0.01 | $2.77 | $33.22 |
| Arkansas | 14.33¢ | $0.01 | $2.58 | $30.95 |
| California | 33.61¢ | $0.03 | $6.05 | $72.60 |
| Colorado | 17.00¢ | $0.01 | $3.06 | $36.72 |
| Connecticut | 24.16¢ | $0.02 | $4.35 | $52.19 |
| Delaware | 18.48¢ | $0.01 | $3.33 | $39.92 |
| District of Columbia | 25.21¢ | $0.02 | $4.54 | $54.45 |
| Florida | 15.03¢ | $0.01 | $2.71 | $32.46 |
| Georgia | 16.27¢ | $0.01 | $2.93 | $35.14 |
| Hawaii | 48.00¢ | $0.04 | $8.64 | $103.68 |
| Idaho | 13.73¢ | $0.01 | $2.47 | $29.66 |
| Illinois | 19.22¢ | $0.01 | $3.46 | $41.52 |
| Indiana | 16.73¢ | $0.01 | $3.01 | $36.14 |
| Iowa | 15.99¢ | $0.01 | $2.88 | $34.54 |
| Kansas | 15.27¢ | $0.01 | $2.75 | $32.98 |
| Kentucky | 13.81¢ | $0.01 | $2.49 | $29.83 |
| Louisiana | 12.72¢ | $0.01 | $2.29 | $27.48 |
| Maine | 32.41¢ | $0.02 | $5.83 | $70.01 |
| Maryland | 21.41¢ | $0.02 | $3.85 | $46.25 |
| Massachusetts | 30.49¢ | $0.02 | $5.49 | $65.86 |
| Michigan | 23.05¢ | $0.02 | $4.15 | $49.79 |
| Minnesota | 17.45¢ | $0.01 | $3.14 | $37.69 |
| Mississippi | 14.54¢ | $0.01 | $2.62 | $31.41 |
| Missouri | 16.09¢ | $0.01 | $2.90 | $34.75 |
| Montana | 14.99¢ | $0.01 | $2.70 | $32.38 |
| Nebraska | 13.78¢ | $0.01 | $2.48 | $29.76 |
| Nevada | 12.77¢ | $0.01 | $2.30 | $27.58 |
| New Hampshire | 26.60¢ | $0.02 | $4.79 | $57.46 |
| New Jersey | 25.19¢ | $0.02 | $4.53 | $54.41 |
| New Mexico | 16.09¢ | $0.01 | $2.90 | $34.75 |
| New York | 29.90¢ | $0.02 | $5.38 | $64.58 |
| North Carolina | 15.16¢ | $0.01 | $2.73 | $32.75 |
| North Dakota | 13.41¢ | $0.01 | $2.41 | $28.97 |
| Ohio | 19.45¢ | $0.01 | $3.50 | $42.01 |
| Oklahoma | 14.35¢ | $0.01 | $2.58 | $31.00 |
| Oregon | 15.97¢ | $0.01 | $2.87 | $34.50 |
| Pennsylvania | 21.72¢ | $0.02 | $3.91 | $46.92 |
| Rhode Island | 28.29¢ | $0.02 | $5.09 | $61.11 |
| South Carolina | 15.47¢ | $0.01 | $2.78 | $33.42 |
| South Dakota | 15.37¢ | $0.01 | $2.77 | $33.20 |
| Tennessee | 13.71¢ | $0.01 | $2.47 | $29.61 |
| Texas | 15.88¢ | $0.01 | $2.86 | $34.30 |
| Utah | 13.12¢ | $0.01 | $2.36 | $28.34 |
| Vermont | 23.75¢ | $0.02 | $4.28 | $51.30 |
| Virginia | 17.55¢ | $0.01 | $3.16 | $37.91 |
| Washington | 14.71¢ | $0.01 | $2.65 | $31.77 |
| West Virginia | 15.78¢ | $0.01 | $2.84 | $34.08 |
| Wisconsin | 19.06¢ | $0.01 | $3.43 | $41.17 |
| Wyoming | 14.36¢ | $0.01 | $2.58 | $31.02 |
Frequently asked questions
How much does it cost to run a box fan all night?
About $0.11 for 8 hours at the U.S. average electricity price.
How much does it cost to run a fan 24 hours a day?
About $0.33 a day for a 75-watt box fan.
Is a fan cheaper than air conditioning?
Far cheaper. A box fan uses about 75 watts; a window air conditioner about 900.
Sources
- U.S. Department of Energy, Energy Saver: Circulating Fans
- U.S. Energy Information Administration, Electric Power Monthly (state electricity prices)
- U.S. Department of Energy, Energy Saver: Appliances and Electronics
Electricity prices are the EIA figures for July 2026. Wattages are typical values; check the label on your own appliance.