How much electricity does heating a sauna use
According to a Motiva energy efficiency expert, a little over an hour of sauna bathing in an ordinary basic sauna consumes an estimated 8–16 kilowatt-hours. The range is wide because consumption is affected by the stove's power, the size of the sauna room, insulation, heating time and how long the stove is on during sauna bathing.
Consumption arises mainly in the heating phase, when the stove, stones and walls warm up. The longer the stove is on before and after bathing, the more electricity is used.
How to calculate the price of a sauna session
Enter the consumption of a sauna session with the total electricity price, which includes energy, transmission and taxes. You can find the total price on your electricity and transmission bills. For example, if the total price is 20 cents per kilowatt-hour, 8 kWh costs €1.60 and 16 kWh €3.20. If you take a sauna three times a week, that adds up to about 156 sessions a year, so consumption on this estimate is about 1,250–2,500 kWh.
You can also estimate your sauna stove's consumption from its power rating. The stove's power in kilowatts multiplied by the hours it is on gives the maximum possible consumption: a 9 kW stove uses at most 9 kWh per hour. Actual consumption is often lower because the thermostat cuts the power once the sauna has heated up. If you have hourly metering, you can also see the consumption of your sauna evenings in your network company's service.
The 20-cent price used in the calculation is only an example. According to Statistics Finland, the total price of electricity for households in June 2026 was 9–10 % higher than a year earlier, so always calculate the cost with the price of your own contract.
Ways to reduce consumption
You can cut consumption without giving up the sauna.
- Heat the sauna only as much as you need and switch off the stove right after bathing.
- Keep the sauna room door closed while heating and check that the door seals tightly.
- Replace weathered sauna stones, as crumbled stone material impairs air circulation.
- If you have a spot-price electricity contract, compare the hourly prices and heat the sauna during a cheaper hour.
- The whole family can take their sauna one after another on the same heating.
Sauna fires and heater safety
According to Tukes, around 120–150 fires start from electric sauna stoves every year that require the rescue service (data from 2020). A significant share of the fires involve items left on or near the stove. A sauna is not a drying room or a storage room, because the stove can switch on by accident.
Keep the safety guards around the sauna stove intact and at the distances given in the user manual. Dilute sauna fragrances in water as instructed, because undiluted they are highly flammable. Do not throw large amounts of water on the stove at once, since the water can end up in the control unit. Checks and repairs of the connection cables are a job for an electrical professional.
Sauna stove lifespan and maintenance
Poor maintenance and using a stove after its technical service life increase the fire risk. The sauna stones should be replaced regularly, and the heating elements and control unit must be inspected if the stove starts to work unevenly, cuts the power or smells burnt. Installing a new stove into the fixed electrical network is electrical work, which must be done by an electrical professional.
Children in the home sauna
A child's body tolerates heat less well than an adult's, because the ability to sweat and the circulatory reserve are smaller. In a study described by Lääkärikirja Duodecim, 10 minutes at 70 degrees raised children's skin temperature by 4–5 degrees and core temperature by about 1.5 degrees, and nearly a third of children under five felt unwell.
So with a child, sauna briefly and at a lower temperature. A child is not left alone in the sauna, the stove is protected with a guard rail, and hot water is kept out of the child's reach. Do not use the sauna with a fever or a vomiting or diarrhoea illness.
Safe sauna bathing
According to the Duodecim Medical Book, 60-degree water causes an adult a deep burn in about five seconds and 70-degree water in less than a second, so keep children away from hot water and the stove. Drink water while in the sauna, as 0,5–1,0 litres of sweat is released at a time. According to Terveyskylä's guidance, a heart patient should keep the sauna temperature below 80 degrees. You can find more sauna information and public saunas in Sauna Radar.
Frequently asked questions
How much electricity does heating a sauna use?
According to a Motiva expert, a little over an hour of sauna bathing in an ordinary basic sauna consumes about 8–16 kWh.
How do I calculate the price of a sauna session?
Enter your consumption (kWh) with the total electricity price, which includes energy, transmission and taxes. For example, 10 kWh at 20 c/kWh costs €2.00.
How many sauna stove fires occur in Finland?
According to Tukes, around 120–150 fires start from electric sauna stoves every year that require a rescue service call-out (data from 2020).
Calculate it yourself
- Sauna calculator: electric heater consumption and heater size · free
- Public sauna profitability calculator · free
Ready-made tools
- Sauna heating cost calculator · Cost of an electric and wood-burning heater per session, per month and per year
Sources
- MTV Uutiset: Motiva expert on the electricity consumption of sauna bathing (2022)
- Statistics Finland: Energy prices 2026, 2nd quarter (24.9.2026)
- Verkkouutiset: A sauna is not a laundry drying room (Tukes, 4.2.2020)
- Health Library: Sauna and health (Duodecim, 30.1.2024)
- Terveyskylä: Heart disease and sauna
The article is general information and does not replace the guidance of an authority, a lawyer or an adviser. Check up-to-date information from the sources.