How much does it cost to run an electric sauna?

For a typical 6 kW home sauna at 17 cents per kWh, a session with a 35 minute heat-up and 45 minutes of use costs roughly 80 cents to $1. Three sessions a week works out to about $10 to $13 a month.

Does a sauna heater draw full power the whole time?

No. It draws close to full rated power during heat-up, then cycles on its thermostat to hold temperature — typically running 25 to 45 percent of the time in a well insulated room. Calculators that assume full draw throughout overstate the cost substantially.

Sauna electricity cost calculator

Enter what you know about your heater and how you use it. The answer updates as you type.

Sauna type

Traditional Infrared

Not sure of your numbers? Start from an example:

Heater size

On the plate or the manual. Most home saunas are 4.5–8 kW.

Electricity price

/ kWh

Per kWh, from your bill. The US average is around $0.17.

Heat-up time

min

Cold room to ready. Usually 30–50 minutes.

Time spent in the sauna

min

Only the part after it is up to temperature.

Sessions per week

Count each heat-up, not each person.

Heater duty while holding 35%

A heater doesn't draw full power once the room is hot — it cycles. 35% is typical for an insulated room; raise it for a cold or glassy one.

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Fill in the fields to see your answer.

Per session—
Per month—
Per year—
kWh per year—

Heating it up —
Holding temperature —

Not sure your heater suits the room? Check the heater size →

What this assumes

Heat-up runs at full rated power. Close to true for an electric heater from cold — the thermostat isn't cutting in yet.
Holding costs less than heating. The duty slider is the share of rated power drawn once the room is at temperature.
Warm-up runs at full power. The heaters stay on until the cabin reaches the temperature you set.
The session runs at 60% to 100% of full power. Makers disagree on whether the heaters cycle once the cabin is warm, so you get a range.
The cabin air may never reach your setting. If it doesn't, the heaters never switch off, and the high end is the better guess.
The calculator assumes nothing about your room. Insulation, ceiling height and outside temperature all change the real duty — which is why that figure is yours to set.
Months are 52.18 weeks ÷ 12, so weekly and annual figures stay consistent with each other.

How this calculation works

Heat-up energy
Hold energy
Cost per session
Per month and year

kWh = kW × (heat-up min ÷ 60) + kW × hold factor × (session min ÷ 60)

Heat-up runs at close to full rated power. Holding temperature does not. The thermostat cycles the element, so the heater draws only a fraction of its rating. Multiply the total by your electricity price, then by sessions per week; annual is 52.18 weeks, and monthly is that divided by twelve.

Energy per session, at a 35% hold factor
Heater	35 min heat-up	+ 45 min sit	Total
4.5 kW	2.6 kWh	1.2 kWh	3.8 kWh
6 kW	3.5 kWh	1.6 kWh	5.1 kWh
8 kW	4.7 kWh	2.1 kWh	6.8 kWh
9 kW	5.3 kWh	2.4 kWh	7.7 kWh

Multiply the total by your rate for cost per session. At $0.17/kWh a 6 kW sauna is about $0.87.

Why the duty figure matters so much

Most sauna cost calculators multiply heater kilowatts by total time. That quietly assumes the heater draws its full rating from the moment you switch it on until you leave, which no thermostatically controlled heater does. Once the room reaches temperature the element cycles — on for a minute, off for two — and average draw falls to somewhere between a quarter and a half of the plate rating.

The practical consequence: a long sit in a hot room is much cheaper than a second heat-up from cold. If two people want a sauna on the same evening, going one after the other costs far less than heating twice.

Typical running costs

Setup	Per session	Per month (3×/week)
4.5 kW, 30 min heat-up, 45 min sit	~$0.60	~$8
6 kW, 35 min heat-up, 45 min sit	~$0.85	~$11
8 kW, 40 min heat-up, 60 min sit	~$1.40	~$18

At $0.17/kWh and a 35% hold duty. Use the calculator with your own rate.

Infrared saunas

An infrared sauna draws much less power than a traditional heater. The models we checked draw 1.35 to 2.7 kW. Most traditional home heaters are 4.5 to 8 kW. Pick Infrared at the top of the calculator to price one.

Power draw of some home infrared saunas
Size	Model	Power	Outlet	Per session
1 person	Sunlighten Signature I	1.35 kW	120 V	$0.13–$0.17
1 person	Sunlighten mPulse Aspire	2.16 kW	120 V	$0.20–$0.28
2 person	Finnmark FD-2	1.75 kW	120 V	$0.16–$0.22
2 person	Clearlight Sanctuary 2	2.26 kW	120 V	$0.21–$0.29
3 person	Clearlight Sanctuary 3	2.68 kW	240 V	$0.25–$0.34

Power is from each model's spec sheet or product page, listed on the sources page. Cost assumes a 15 minute warm-up, a 30 minute session and $0.17/kWh.

Check the outlet before you buy. The 3-person model needs 240 volts. Three of the four 120-volt models also need a 20-amp circuit.

Why infrared shows a range

Infrared makers disagree on what the heaters do once the cabin is warm. Health Mate's manual says the heaters turn off and on to hold the temperature. Clearlight tells owners to set the thermostat to the top so the heaters run for the whole session. The calculator prices both. The low end has the heaters on 60% of the time, and the high end has them on all session.

How much does an infrared sauna cost to run?

A 2 kW infrared sauna costs about $0.19 to $0.26 a session at 17 cents per kWh. That assumes a 15 minute warm-up and a 30 minute session. At three sessions a week, that comes to about $2.40 to $3.30 a month. Check the power rating of your own model. The ones we checked draw 1.35 to 2.7 kW.

Inside a wood-lined sauna with tiered benches and a stone-topped heater in the corner — A typical home sauna: the heater sits in the corner, and the room's insulation decides how hard it has to work.

Want the longer version? What a home sauna really costs to run goes through why the usual estimate is too high, and how sauna heater sizing works covers picking the right heater in the first place.

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