The short answer
A 6 kW electric sauna costs up to about $1.27 a session (40 minutes to heat, 30 to use) at the U.S. average electricity rate of 18.16¢ per kWh (August 2026). Three sessions a week comes to up to $16.53 a month; the heater's thermostat usually brings the real figure lower.
The same sauna in every state
A 6 kW heater, 40 + 30 minutes a session, 3 sessions a week, at each state's average residential rate (August 2026).
| Alabama | $1.14 | $14.86 | 16.33¢ |
|---|---|---|---|
| Alaska | $2.06 | $26.76 | 29.41¢ |
| Arizona | $1.05 | $13.70 | 15.05¢ |
| Arkansas | $1.01 | $13.08 | 14.37¢ |
| California | $2.08 | $27.07 | 29.75¢ |
| Colorado | $1.20 | $15.62 | 17.17¢ |
| Connecticut | $1.72 | $22.30 | 24.51¢ |
| Delaware | $1.31 | $17.02 | 18.70¢ |
| District of Columbia | $1.82 | $23.64 | 25.98¢ |
| Florida | $1.05 | $13.64 | 14.99¢ |
| Georgia | $1.11 | $14.47 | 15.90¢ |
| Hawaii | $3.30 | $42.93 | 47.18¢ |
| Idaho | $0.94 | $12.17 | 13.37¢ |
| Illinois | $1.35 | $17.58 | 19.32¢ |
| Indiana | $1.19 | $15.49 | 17.02¢ |
| Iowa | $1.19 | $15.52 | 17.06¢ |
| Kansas | $1.08 | $14.08 | 15.47¢ |
| Kentucky | $0.97 | $12.56 | 13.80¢ |
| Louisiana | $0.90 | $11.71 | 12.87¢ |
| Maine | $2.25 | $29.22 | 32.11¢ |
| Maryland | $1.50 | $19.47 | 21.40¢ |
| Massachusetts | $2.13 | $27.74 | 30.48¢ |
| Michigan | $1.61 | $20.92 | 22.99¢ |
| Minnesota | $1.20 | $15.65 | 17.20¢ |
| Mississippi | $1.01 | $13.13 | 14.43¢ |
| Missouri | $1.12 | $14.58 | 16.02¢ |
| Montana | $1.09 | $14.17 | 15.57¢ |
| Nebraska | $0.95 | $12.32 | 13.54¢ |
| Nevada | $0.89 | $11.58 | 12.72¢ |
| New Hampshire | $1.93 | $25.15 | 27.64¢ |
| New Jersey | $1.72 | $22.40 | 24.61¢ |
| New Mexico | $1.16 | $15.02 | 16.51¢ |
| New York | $2.01 | $26.07 | 28.65¢ |
| North Carolina | $1.05 | $13.60 | 14.95¢ |
| North Dakota | $0.93 | $12.11 | 13.31¢ |
| Ohio | $1.36 | $17.64 | 19.38¢ |
| Oklahoma | $1.04 | $13.49 | 14.82¢ |
| Oregon | $1.11 | $14.49 | 15.92¢ |
| Pennsylvania | $1.52 | $19.81 | 21.77¢ |
| Rhode Island | $1.97 | $25.64 | 28.18¢ |
| South Carolina | $1.10 | $14.34 | 15.76¢ |
| South Dakota | $1.06 | $13.79 | 15.15¢ |
| Tennessee | $0.94 | $12.21 | 13.42¢ |
| Texas | $1.11 | $14.48 | 15.91¢ |
| Utah | $0.93 | $12.11 | 13.31¢ |
| Vermont | $1.67 | $21.69 | 23.84¢ |
| Virginia | $1.23 | $16.05 | 17.64¢ |
| Washington | $1.02 | $13.31 | 14.63¢ |
| West Virginia | $1.14 | $14.84 | 16.31¢ |
| Wisconsin | $1.36 | $17.66 | 19.41¢ |
| Wyoming | $1.01 | $13.13 | 14.43¢ |
How it works
The formula
cost = kWh × rate
Assumptions
- Heaters: Harvia rates its 4.5 kW heater for 3 to 6 m³, its 6 kW Virta for about 177 to 297 cu ft and its 8 kW KV80E for 247 to 424 cu ft.
- Upper bound: full power for the heat-up (typically 30 to 45 minutes) and the whole session. The thermostat cycles the heater once the room is hot, so the real cost is lower.
- Infrared saunas use smaller heaters; type the watts on the label (1.5 kW = 1500 W).
Worked example: three sessions a week
- 6 kW × 70 minutes ÷ 60 = 7 kWh
- × 18.16¢ = $1.27 a session
- × 3 a week = $16.53 a month
Ways to cut the cost
- Don't over-preheat: start the heater only as long before as it needs.
- Keep the door shut and the room insulated; every opening dumps heat.
- Share sessions: the heat-up costs the same for one person or four.
Questions people ask
How much does it cost to run a sauna?
A 6 kW electric sauna heated for 40 minutes and used for 30 uses up to 7 kWh, about $1.27 a session at the U.S. average of 18.16¢ per kWh (EIA, August 2026). Three sessions a week is up to $16.53 a month: $11.58 in Nevada, $42.93 in Hawaii.
How long does a sauna take to heat up?
About 30 to 45 minutes for a typical electric sauna, longer in a cold room or with a heater too small for the space.
What size sauna heater do I need?
Makers size heaters by room volume: Harvia rates a 4.5 kW heater for 3 to 6 m³ and an 8 kW heater for about 247 to 424 cu ft. Glass walls and uninsulated walls need a bigger heater.
Why is this "at most"?
Once the room is hot, the heater's thermostat cycles it off and on, so it uses less than full power for the whole session. A plug-in or circuit energy monitor shows the real figure.