How much does a sauna cost to run each month?

No. 01

The cost comes down to four numbers

Multiply the heater's kW by the hours it's on, then by the share of that time it draws full power, then by your rate. A 6 kW heater on for an hour at 60% uses 3.6 kWh. At 17.3 cents, that's 62 cents.

Count the warm-up in the hours. An electric heater runs flat out while the stones heat, then switches on and off to hold the room, which is why we use 60% for a whole session. That share is our assumption, and a cold barrel in January will draw more than a warm basement room in June.

No. 02

Your state can triple the bill

Electricity prices vary more across the country than heater sizes do. The table gives every state's 2025 residential average from the EIA, with the cost of one hour in a 6 kW sauna and a month of four sessions a week.

No. 03

Infrared cabins cost less per session

An infrared cabin draws far less power than a hot-rock heater. A 2 kW cabin on for 45 minutes, drawing full power about 70% of that time, costs about 18 cents a session at the US average, by our math, or a little over $3 a month at four sessions a week.

The comparison isn't like for like, because an infrared cabin and a hot-rock sauna make different rooms. Our roundup covers both.

No. 04

A wood stove trades the meter for the woodpile

A wood-fired sauna draws no electricity, so its cost is the firewood you burn. The calculator lets you set a cost per session. If you buy cordwood, divide what a cord costs you by the number of firings it gives you. Our wood stove guide covers the stoves built here.

No. 05

How we worked out these numbers

The rates are the EIA's 2025 residential averages by state from Electric Power Monthly Table 5.6.B, which the EIA marks as preliminary, read Oct 10, 2026. The 60% and 70% duty cycles are our assumptions for a session that includes warm-up. Your bill adds fixed charges and taxes that a per-kWh average leaves out, so use your own rate when you have it.