By the Garden Sauna Guide UK Team · Updated May 2026 · Independent, reader-supported

Wood-Fired vs Electric Sauna Running Costs UK: Which Is Cheaper to Operate?

If you're planning to install a garden sauna in the UK, fuel costs are often the deciding factor. While a wood-fired sauna has charm and a lower upfront energy cost per session, the maths might surprise you. Here's what you actually spend to run each type, month after month.

Electric Sauna Running Costs

An electric sauna is the simpler calculation. Most UK domestic models draw 6–8 kW, though smaller 4 kW units and larger 10+ kW commercial-grade models exist.

Per-session cost: A typical 1-hour session uses 6 kWh. At the current UK electricity rate of roughly 24–28p per kilowatt-hour (depending on your provider and tariff), that's £1.44–£1.68 per session.

Weekly and annual costs:

• 3 sessions per week: £4.32–£5.04 per week, or £225–£262 per year
• 4 sessions per week: £5.76–£6.72 per week, or £299–£349 per year

Electricity prices have stabilised somewhat since 2022–2023, but remain volatile. If energy prices spike—or if you're on a standard variable tariff—your running costs will climb. Electric sauna heating is efficient (typically 90%+ of energy converts to heat), so there's little waste.

Hidden costs: Annual servicing of heating elements and thermostats is minimal. Electric saunas rarely need structural maintenance beyond dust cleaning.

Wood-Fired Sauna Running Costs

Wood-fired saunas have a seductive appeal: once you own one, "free heat from the forest" feels cheap. In practice, the running costs depend entirely on fuel quality and supply.

Fuel costs: In the UK, kiln-dried hardwood suitable for sauna use (low moisture, good heat output) costs £15–25 per 10 kg bag from specialist suppliers. Quality hardwoods like oak, birch, or ash are preferable to softwoods like pine, which produce more creosote and require more frequent chimney cleaning.

A typical 1-hour session burning wood-fired heat requires 2–4 kg of kiln-dried wood, depending on desired temperature, outdoor weather, and sauna size. Budget £5–10 per session for fuel alone—a firewood cost of roughly £1.25–2.50 per kilogram.

Weekly and annual costs:

• 3 sessions per week: £15–30 per week, or £780–£1,560 per year (fuel only)
• 4 sessions per week: £20–40 per week, or £1,040–£2,080 per year

Additional costs: Wood-fired saunas require annual chimney sweeping (£80–150), grate repairs or replacement (occasional, £20–100), and seasoned wood storage in a dry shed or cover. Poor storage means waterlogged wood and drastically higher fuel consumption.

The Real Running Cost: Breakeven Point

Electric saunas have high upfront costs (£1,200–3,500 installed) but cheap operation. Wood-fired models often cost less to install (£800–2,500), but running costs climb rapidly.

If you use your sauna 3 times per week:

• Electric sauna: £225–262 per year to run
• Wood-fired sauna: £780–1,560 per year to run

The electric sauna is cheaper to operate by roughly £500–1,300 per year—enough to offset a higher purchase price within 1–3 years.

If you use it once per week:

• Electric: £75–87 per year
• Wood-fired: £260–520 per year

Even light use favours electric from a running-cost perspective.

Wood-fired saunas break even only if you either (a) have a free, abundant local firewood supply, (b) are willing to fell and season your own timber, or (c) use the sauna very infrequently and treat firewood as a minor cost.

Factors Beyond Fuel Cost

Installation and venting: Electric saunas need a stable 32A or 40A supply; installing this can cost £500–1,000. Wood-fired saunas need a chimney, flue, or external vent; that installation cost often exceeds the sauna purchase itself.

Heating speed: Electric saunas reach operating temperature in 30–45 minutes. Wood-fired can take 60–90 minutes and require active tending to maintain steady heat.

Maintenance burden: Electric saunas are near-passive. Wood-fired saunas demand chimney sweeping, wood sourcing, and storage management year-round.

Fuel availability: If you live far from timber suppliers or have limited storage space, wood costs rise or become impractical. Urban and suburban UK gardens often rule out regular firewood delivery.

Year-round use: Wood-fired saunas are less convenient in winter; icy steps, snow on the roof, and wet firewood create safety and efficiency hazards. Electric saunas operate safely in any season.

Which Is Actually Cheaper?

For most UK homeowners, electric saunas are cheaper to run—sometimes dramatically so—and require far less management. The running cost advantage is around £500–1,300 per year for regular users.

Wood-fired saunas make sense only if you have a reliable firewood supply (your own woodland, a local forester relationship, or low-cost bulk access), use the sauna infrequently, or prioritise the ritual and atmosphere of a wood-fired experience over operational economy.

When comparing saunas, factor in the full picture: purchase price, installation cost, annual fuel or electricity, maintenance, and the effort involved. Many UK buyers discover that an electric sauna's simplicity and predictable running costs align better with their lifestyle than a romantic but fuel-hungry wood-fired model.