Humidifier: electricity cost calculator
Quick answer: a typical humidifier costs about $2/month while in use at the U.S. average electricity price (18.44¢/kWh) across a 5-month season (about $11/year). Your number depends on wattage, runtime and your state — calculate it below.
Cool-mist and evaporative humidifiers draw 20–60 W. Warm-mist (steam) models boil water at 250–350 W — an order of magnitude more for the same room.
0.40 kWh/day used · 12 kWh/month in use · 61 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 | 20 W | 6.0 h | $0.67 |
| Typical | 40 W | 10.0 h | $2.25 |
| Heavy use | 300 W | 15.0 h | $25.26 |
Common questions
Warm mist vs cool mist — cost difference?
A 300 W steam unit running 10 hours costs about $0.55 per day at the U.S. average price; a 40 W evaporative unit about $0.07. Over a winter that's a $60+ difference.
Cost in every state
Monthly cost of a typical humidifier (40 W, 10h/day) at each state's average residential price, May 2026.
| State | Avg price | Per month |
|---|---|---|
| Alabama | 16.77¢ | $2.04 |
| Alaska | 28.23¢ | $3.44 |
| Arizona | 15.23¢ | $1.85 |
| Arkansas | 14.36¢ | $1.75 |
| California | 33.25¢ | $4.05 |
| Colorado | 16.16¢ | $1.97 |
| Connecticut | 27.37¢ | $3.33 |
| Delaware | 19.38¢ | $2.36 |
| District of Columbia | 25.40¢ | $3.09 |
| Florida | 15.17¢ | $1.85 |
| Georgia | 15.84¢ | $1.93 |
| Hawaii | 52.00¢ | $6.33 |
| Idaho | 12.35¢ | $1.50 |
| Illinois | 23.85¢ | $2.90 |
| Indiana | 18.15¢ | $2.21 |
| Iowa | 14.14¢ | $1.72 |
| Kansas | 15.13¢ | $1.84 |
| Kentucky | 14.98¢ | $1.82 |
| Louisiana | 14.15¢ | $1.72 |
| Maine | 28.63¢ | $3.49 |
| Maryland | 21.77¢ | $2.65 |
| Massachusetts | 28.82¢ | $3.51 |
| Michigan | 22.01¢ | $2.68 |
| Minnesota | 16.95¢ | $2.06 |
| Mississippi | 16.16¢ | $1.97 |
| Missouri | 13.68¢ | $1.67 |
| Montana | 14.67¢ | $1.79 |
| Nebraska | 13.59¢ | $1.65 |
| Nevada | 13.60¢ | $1.66 |
| New Hampshire | 27.33¢ | $3.33 |
| New Jersey | 23.27¢ | $2.83 |
| New Mexico | 14.12¢ | $1.72 |
| New York | 29.93¢ | $3.64 |
| North Carolina | 15.09¢ | $1.84 |
| North Dakota | 13.61¢ | $1.66 |
| Ohio | 19.52¢ | $2.38 |
| Oklahoma | 13.38¢ | $1.63 |
| Oregon | 16.27¢ | $1.98 |
| Pennsylvania | 21.55¢ | $2.62 |
| Rhode Island | 29.46¢ | $3.59 |
| South Carolina | 16.18¢ | $1.97 |
| South Dakota | 15.73¢ | $1.92 |
| Tennessee | 14.47¢ | $1.76 |
| Texas | 16.44¢ | $2.00 |
| Utah | 12.96¢ | $1.58 |
| Vermont | 24.89¢ | $3.03 |
| Virginia | 17.61¢ | $2.14 |
| Washington | 14.95¢ | $1.82 |
| West Virginia | 16.80¢ | $2.05 |
| Wisconsin | 19.74¢ | $2.40 |
| Wyoming | 14.80¢ | $1.80 |
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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.