Whole-house fan: electricity cost calculator
Quick answer: a typical whole-house fan costs about $7/month while in use at the U.S. average electricity price (18.44¢/kWh) across a 5-month season (about $34/year). Your number depends on wattage, runtime and your state — calculate it below.
A whole-house fan draws 200–700 W while pulling cool outdoor air through open windows and exhausting hot air through the attic. Run for 2–4 evening hours it can replace AC entirely on mild days.
1.20 kWh/day used · 37 kWh/month in use · 183 kWh/year at 18.44¢ per kWh (5 months of use per year)
Low, typical and heavy use
Monthly cost while in use, at the U.S. average price of 18.44¢/kWh.
| Scenario | Watts | Hours/day | Per month |
|---|---|---|---|
| Light use | 200 W | 1.8 h | $2.02 |
| Typical | 400 W | 3.0 h | $6.74 |
| Heavy use | 700 W | 4.5 h | $17.68 |
Common questions
How much does a whole-house fan save vs AC?
At 400 W it uses about a tenth of a central AC's power. Each evening you cool the house with the fan instead of AC saves roughly $1–2 at average prices.
Cost in every state
Monthly cost of a typical whole-house fan (400 W, 3h/day) at each state's average residential price, May 2026.
| State | Avg price | Per month |
|---|---|---|
| Alabama | 16.77¢ | $6.13 |
| Alaska | 28.23¢ | $10.31 |
| Arizona | 15.23¢ | $5.56 |
| Arkansas | 14.36¢ | $5.24 |
| California | 33.25¢ | $12.14 |
| Colorado | 16.16¢ | $5.90 |
| Connecticut | 27.37¢ | $10.00 |
| Delaware | 19.38¢ | $7.08 |
| District of Columbia | 25.40¢ | $9.28 |
| Florida | 15.17¢ | $5.54 |
| Georgia | 15.84¢ | $5.79 |
| Hawaii | 52.00¢ | $18.99 |
| Idaho | 12.35¢ | $4.51 |
| Illinois | 23.85¢ | $8.71 |
| Indiana | 18.15¢ | $6.63 |
| Iowa | 14.14¢ | $5.16 |
| Kansas | 15.13¢ | $5.53 |
| Kentucky | 14.98¢ | $5.47 |
| Louisiana | 14.15¢ | $5.17 |
| Maine | 28.63¢ | $10.46 |
| Maryland | 21.77¢ | $7.95 |
| Massachusetts | 28.82¢ | $10.53 |
| Michigan | 22.01¢ | $8.04 |
| Minnesota | 16.95¢ | $6.19 |
| Mississippi | 16.16¢ | $5.90 |
| Missouri | 13.68¢ | $5.00 |
| Montana | 14.67¢ | $5.36 |
| Nebraska | 13.59¢ | $4.96 |
| Nevada | 13.60¢ | $4.97 |
| New Hampshire | 27.33¢ | $9.98 |
| New Jersey | 23.27¢ | $8.50 |
| New Mexico | 14.12¢ | $5.16 |
| New York | 29.93¢ | $10.93 |
| North Carolina | 15.09¢ | $5.51 |
| North Dakota | 13.61¢ | $4.97 |
| Ohio | 19.52¢ | $7.13 |
| Oklahoma | 13.38¢ | $4.89 |
| Oregon | 16.27¢ | $5.94 |
| Pennsylvania | 21.55¢ | $7.87 |
| Rhode Island | 29.46¢ | $10.76 |
| South Carolina | 16.18¢ | $5.91 |
| South Dakota | 15.73¢ | $5.75 |
| Tennessee | 14.47¢ | $5.29 |
| Texas | 16.44¢ | $6.00 |
| Utah | 12.96¢ | $4.73 |
| Vermont | 24.89¢ | $9.09 |
| Virginia | 17.61¢ | $6.43 |
| Washington | 14.95¢ | $5.46 |
| West Virginia | 16.80¢ | $6.14 |
| Wisconsin | 19.74¢ | $7.21 |
| Wyoming | 14.80¢ | $5.41 |
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Methodology & sources
Cost = watts ÷ 1,000 × hours × price per kWh. Electricity prices are average residential prices by state from the EIA Electric Power Monthly, Table 5.6.A (May 2026). EIA averages include delivery charges and taxes but are not any specific utility tariff — for an exact figure, use the rate from your own bill. Wattage presets reflect common product ranges; check your appliance's nameplate or a plug-in power meter for its true draw.
Last verified: July 30, 2026. Prices refresh automatically each month when EIA publishes new data.