How Much Does a Sauna Cost to Run in the UK? | KOVE

The cost of running a sauna in the UK depends primarily on the power of the sauna heater, your electricity tariff and how long the sauna is switched on.

As a simple example, a 2kW infrared sauna running continuously for one hour at an electricity price of 25p per kWh would use up to 2kWh of electricity, costing around 50p for that hour.

A larger traditional sauna with a 6kW heater would have a theoretical maximum consumption of 6kWh over an hour, equivalent to around £1.50 at the same electricity price.

Real-world consumption isn't always as simple as multiplying the heater rating by your session time, though. Once a sauna reaches its target temperature, thermostatic control can cycle the heater rather than requiring maximum output continuously.

Here's how to calculate what your own sauna could cost to run.

Sauna Running Costs: The Quick Answer

These figures use an example electricity rate of 25p per kWh and assume the heater draws its full rated power continuously for the entire hour. They're useful for comparison, but shouldn't be treated as guaranteed real-world running costs.

How Do You Calculate the Cost of Running a Sauna?

You only need three numbers:

• The sauna's power consumption in kilowatts (kW)
• Your electricity price in pence per kilowatt-hour (kWh)
• How long the sauna is operating

The basic calculation is:

Power (kW) × time (hours) × electricity price (£/kWh) = electricity cost

So if your sauna uses 4.5kW and your electricity costs £0.25 per kWh:

4.5 × 1 × £0.25 = £1.125

That gives a theoretical maximum electricity cost of approximately £1.13 for one hour at full power.

How Much Does an Infrared Sauna Cost to Run?

Infrared saunas generally have lower rated power requirements than traditional electric saunas.

That's partly because they work differently.

A traditional sauna uses a powerful heater to bring the entire cabin to a high air temperature, often somewhere around 70–100°C.

An infrared sauna uses infrared heaters to transfer radiant heat towards the body and typically operates at a considerably lower air temperature.

For example, a compact KOVE indoor infrared sauna rated at approximately 1.75kW would have a theoretical maximum electricity cost of:

1.75kW × £0.25 = approximately 44p per hour.

Even if you used it four times per week for one hour each time, that theoretical maximum would be around:

£1.75 per week

or roughly:

£7.60 per month.

Again, that's based on the example 25p/kWh tariff and assumes continuous full-rated power consumption.

How Much Does a 2.5kW Infrared Sauna Cost to Run?

At 25p per kWh, the calculation is:

2.5 × £0.25 = £0.625

So the theoretical maximum is approximately 63p per hour.

If you used the sauna three times each week for an hour, that would be approximately £1.88 per week at continuous full power.

This is one reason an infrared sauna can be attractive for someone who expects to use their sauna frequently.

How Much Does an Outdoor Sauna Cost to Run?

Traditional outdoor saunas usually require substantially more powerful heaters than infrared cabins.

KOVE's outdoor sauna range uses different heater sizes depending on the volume of the cabin.

For example, smaller cabins may use a 4.5kW heater, while larger barrel saunas and cube saunas can require 6kW, 8kW or larger heaters.

Using the same example electricity tariff of 25p/kWh:

However, there's an important distinction between heater rating and actual electricity consumed during an entire session.

Does a 6kW Sauna Heater Always Use 6kW?

No. A 6kW rating tells you the heater's power at full output; it doesn't necessarily mean it continuously draws 6kW for every minute the sauna is switched on.

During the initial heating period, a traditional sauna heater may operate at or near full output as it brings the cabin up to temperature.

Once the desired temperature is reached, thermostatic control can switch heating elements on and off to maintain it.

The actual electricity consumed over a complete session therefore depends on factors including:

• Outside temperature
• Starting temperature inside the sauna
• Desired sauna temperature
• Cabin size
• Insulation
• Glass area
• How frequently the door is opened
• Session duration

That's why multiplying heater kW by total session time is best considered a straightforward upper-bound calculation, rather than a precise prediction of every session's energy consumption.

Does a Sauna Use More Electricity in Winter?

An outdoor sauna can require more energy in colder conditions because there's a greater temperature difference between the environment outside and the desired temperature inside the cabin.

Imagine heating the same sauna to 85°C on two different days.

If it's 20°C outside, you're asking the sauna to overcome roughly a 65°C temperature difference.

If it's 0°C outside, that difference becomes approximately 85°C.

The sauna also continually loses some heat to its surroundings.

Insulation, timber construction, glazing and weather conditions therefore all affect real-world energy use.

How Much Does It Cost to Heat a Sauna From Cold?

This depends on both heater power and heat-up time.

As a simple worst-case example, imagine a 6kW heater operating continuously at full output during a 45-minute warm-up.

Forty-five minutes is 0.75 hours.

The calculation would therefore be:

6kW × 0.75 hours = 4.5kWh

At 25p/kWh:

4.5 × £0.25 = £1.125

So that hypothetical warm-up would cost approximately £1.13.

If you then used the sauna for another 30 minutes, the heater might cycle as required to maintain temperature rather than necessarily remaining at full output throughout.

Does a Bigger Sauna Cost More to Run?

Generally, yes.

A larger cabin contains more air and has a greater surface area through which heat can escape, so it generally requires a more powerful heater.

That's why sauna heaters should be matched to the volume and construction of the cabin.

For example, KOVE's compact cube saunas use smaller heaters than the largest models in our outdoor cube sauna range.

Putting an undersized heater into a large sauna isn't necessarily a good way to save electricity either.

If the heater has to work continuously and struggles to bring the cabin to the desired temperature, you've compromised the sauna experience without necessarily achieving the saving you expected.

Is an Infrared Sauna Cheaper to Run Than a Traditional Sauna?

On rated electrical power alone, a typical home infrared sauna will usually cost less per hour to operate than a traditional electric sauna with a 4.5kW, 6kW or 8kW heater.

For example, at our illustrative 25p/kWh rate:

• 1.75kW infrared sauna: up to approximately 44p/hour
• 2.5kW infrared sauna: up to approximately 63p/hour
• 4.5kW traditional sauna: up to approximately £1.13/hour
• 6kW traditional sauna: up to approximately £1.50/hour
• 8kW traditional sauna: up to approximately £2.00/hour

But running cost isn't the only reason to choose one over the other.

An infrared sauna and a traditional sauna provide distinctly different experiences.

If you want high-temperature Finnish-style sauna bathing, sauna stones and löyly, a traditional sauna is the appropriate comparison.

If you prefer lower-temperature radiant heat and straightforward indoor use, an infrared sauna may suit you better.

What Is the Cheapest Type of Sauna to Run?

If we're looking purely at electrical consumption, smaller infrared and portable sauna products generally have substantially lower power requirements than large traditional outdoor saunas.

But we'd be wary of choosing a sauna based entirely on which one costs the least per hour.

A portable sauna, infrared cabin and traditional outdoor sauna aren't identical products at three different prices.

They offer very different experiences.

The better question is: which sauna experience do you actually want, and what will that cost you to run?

How Much Would It Cost to Sauna Three Times Per Week?

We can illustrate this using maximum rated consumption and a 25p/kWh electricity price.

*Monthly figures use approximately 4.345 weeks per month. All figures assume continuous full-rated power throughout every session, so actual consumption may be lower where thermostatic controls cycle the heater.

How Can You Reduce Sauna Running Costs?

You don't need to obsess over every penny, but there are some sensible ways to avoid wasting energy.

1. Don't Preheat It for Longer Than Necessary

If your sauna is ready, use it.

Leaving a sauna sitting at temperature for an extra hour before you get in simply uses additional energy.

2. Keep the Door Closed

Opening the door allows hot air to escape and cooler air to enter.

You're not going to ruin a session by opening the door once, but repeatedly doing it makes the heater work harder.

3. Choose the Right Heater

A properly sized heater allows the sauna to reach and maintain its intended operating temperature.

Bigger isn't automatically better, and smaller isn't automatically more economical.

4. Use Timers Where Available

Controls and timers can help ensure the sauna isn't left operating unnecessarily.

5. Pick a Sauna That Matches How You'll Actually Use It

If you're the only person using the sauna every morning, you may not need a six-person cabin.

Likewise, if sauna is going to be something the whole family uses together, buying something too small purely to reduce its heater size isn't particularly useful.

Does a Home Sauna Use a Lot of Electricity?

It depends on what you mean by a lot.

A small infrared sauna may have a rated power similar to some common high-powered household appliances.

A large traditional sauna heater is a substantially more powerful electrical load and will therefore consume considerably more energy while operating.

But saunas generally operate for relatively short periods rather than continuously throughout the day.

The best way to understand the impact on your own electricity bill is therefore to calculate:

heater power × your actual usage × your electricity tariff.

That gives a much more useful answer than simply asking whether saunas are expensive to run.

Sauna Running Cost FAQs

How much does a sauna cost to run per hour?

Multiply the sauna's rated power in kW by your electricity tariff in £/kWh. For example, a 2kW sauna at 25p/kWh would cost a maximum of around 50p for one hour if it continuously drew its full rated power.

How much does a 6kW sauna heater cost to run?

At an example electricity price of 25p/kWh, a 6kW heater running continuously at full power would cost £1.50 per hour.

How much does an 8kW sauna heater cost to run?

At 25p/kWh, an 8kW heater continuously operating at full output would cost approximately £2.00 per hour.

Do sauna heaters run continuously?

Not necessarily. A heater may operate heavily while bringing the sauna up to temperature and then cycle as thermostatic controls maintain the target temperature. This means rated power multiplied by total operating time can overestimate actual consumption.

Are infrared saunas expensive to run?

Home infrared saunas generally have lower power ratings than traditional electric saunas. A 1.75kW infrared sauna, for example, has a theoretical maximum electricity cost of about 44p per hour at a 25p/kWh tariff.

Is a home sauna expensive to run in the UK?

Running costs vary considerably by sauna. Smaller infrared models may cost well under £1 per hour at typical domestic electricity prices, while large traditional electric heaters can cost several pounds per hour when operating continuously at full power.

Does an outdoor sauna cost more to run in winter?

Cold ambient temperatures increase heat loss and the temperature difference the sauna needs to overcome, so an outdoor sauna may require more energy to heat and maintain its temperature during cold weather.

The Bottom Line

The simplest way to estimate your sauna's running cost is:

Sauna power (kW) × hours used × electricity price (£/kWh).

At an example electricity tariff of 25p/kWh, that means a 1.75kW infrared sauna has a theoretical maximum cost of around 44p per hour, while a 6kW traditional heater would cost around £1.50 per hour if it ran continuously at full output.

Actual energy use can be lower once thermostatic control begins cycling the heater.

Most importantly, don't choose a sauna purely because one heater uses fewer kilowatts than another.

An indoor infrared sauna, portable sauna, traditional barrel sauna and outdoor cube sauna offer different experiences.

Work out which sauna you actually want first. Then work out what it'll cost you to use it.