A hot tub can be heated two very different ways. An electric tub runs on a heater, pump and control panel, holding the water at temperature so it is ready whenever you lift the cover. A wood-fired tub uses a stove, either inside the tub or beside it, to heat the water when you want to soak. Both end in the same place, a deep tub of hot water under an open sky, but the daily experience, the installation and the running costs are not the same. This guide compares electric and wood-fired hot tubs honestly, with estimated costs and clear assumptions, so you can decide which suits your home and routine.
How Each Type Works
Electric hot tubs
A typical full-size electric hot tub has an acrylic or rotomolded shell, foam insulation, a heater of roughly 4 to 5.5 kW, one or more pumps for jets and circulation, a filter and an insulated cover. The control system keeps the water at your chosen temperature around the clock. Most full-size models need a dedicated 240V circuit, commonly 40 to 50 amps, with GFCI protection. Smaller 120V "plug and play" models exist, but their heaters are much smaller and they warm the water slowly.
Wood-fired hot tubs
A wood-fired tub is heated by burning firewood in a stove. With an internal stove, the firebox sits inside the tub, surrounded by water, so heat transfers directly. With an external stove, water circulates between the tub and a stove outside it, usually by natural convection. The Starlight wood-burning hot tub, for example, is heated by an internal wood stove and starts at $5,505. Most wood-fired tubs have no pumps, jets or electronics, although some owners add simple accessories such as a cover or a thermometer.
Side-by-Side Comparison
| Factor | Electric hot tub | Wood-fired hot tub |
|---|---|---|
| Power needed | 240V dedicated circuit (commonly 40 to 50 amp) for full-size models | None for heating |
| Ready to use | Always, at set temperature | After you light the stove and wait |
| Typical heat-up from cool water (estimate) | Many hours, often overnight after a fresh fill | About 2 to 4 hours, depending on volume, start temperature and wood |
| Jets and massage | Usually yes | Usually no |
| Temperature control | Precise, digital | Manual, by managing the fire |
| Siting | Near a power source | Anywhere with a level base and safe stove clearances |
| Moving parts to maintain | Pumps, heater, control board, sensors | Stove, chimney, drain valve |
| Water care | Filtration plus regular sanitizer | Frequent draining and refilling, or sanitizer if water is kept |
Heat-Up Time in Real Terms
This is the biggest practical difference between the two.
An electric tub rarely heats from cold. After the initial fill, it may take 12 to 24 hours or more to reach about 100 to 104°F, because a 4 to 5.5 kW heater typically raises a full-size tub by only a few degrees per hour. After that, it maintains temperature continuously. In daily use, it is effectively instant.
A wood-fired tub heats on demand. With an internal stove, bringing a few hundred gallons of cool water up to soaking temperature commonly takes about 2 to 4 hours. Warmer starting water, a cover during heating and dry hardwood all shorten that time. Many owners light the fire in the late afternoon and soak in the evening. If you keep the water from one day to the next with a cover on, reheating is faster.
Running Cost Estimates
Costs depend heavily on climate, how often you soak and local prices, so treat the figures below as estimates only.
Electric
Assumptions: a well-insulated full-size tub with a good cover, kept at about 102°F year-round, electricity at $0.17 per kWh. In a mild climate, monthly heating and pump costs of roughly $25 to $40 are a reasonable estimate. In a cold climate with frequent winter use, roughly $40 to $70 per month is more typical. Older tubs, worn covers and windy sites cost more.
Wood-fired
Assumptions: about 400 gallons of water heated from 50°F to 102°F, dry seasoned hardwood at roughly 6,500 BTU per pound, and an internal stove transferring around 60 percent of the wood's energy into the water. That works out to roughly 35 to 60 pounds of wood per full heat-up. If a cord of seasoned hardwood costs about $300 and weighs around 3,500 pounds, each full heat-up uses roughly $3 to $5 of firewood. Soaking twice a week would be about $25 to $45 per month in wood, less if you reheat water kept warm under a cover, and close to nothing if you have your own supply.
The honest takeaway: the two can cost similar amounts per month. Electric costs more for constant readiness; wood costs more in time and effort per soak.
Installation and Site Requirements
Electric
- A level, load-bearing base such as a concrete pad or reinforced deck. A filled tub with people in it can weigh several thousand pounds.
- A 240V GFCI-protected circuit installed by a licensed electrician, plus a disconnect within sight of the tub where code requires it. Estimated electrical costs commonly range from about $800 to $3,000 depending on distance from the panel.
- Access for service to the pump and control equipment.
Wood-fired
- A level, non-combustible or well-protected base. Gravel, pavers or concrete work well.
- Safe clearances from the stove and chimney to buildings, fences and overhanging branches, as stated by the manufacturer.
- A way to fill the tub, typically a garden hose, and a place for drained water to go.
- A check of local burn rules. Some areas restrict outdoor wood burning on certain days.
Because it needs no electrical run, a wood-fired tub often suits cabins, remote corners of a property or homes where adding a large circuit would require a panel upgrade.
Water Care and Maintenance
Electric tubs are designed to keep the same water for months, using filtration and a sanitizer such as chlorine or bromine, with periodic draining and cleaning. Expect ongoing costs for chemicals and filters, and occasional repairs to pumps, heaters or control boards over the life of the tub.
Wood-fired tubs are simpler mechanically. Many owners change the water frequently, sometimes after every few uses, which reduces the need for chemicals. If you prefer to keep the water longer, you will still need a sanitizer and a cover. Maintenance centers on the stove: removing ash, checking the chimney and gaskets, and keeping the tub clean. There is very little that can break.
The Experience
This is where preference wins over spreadsheets. An electric tub is about convenience: a quick soak before bed, jets on sore shoulders, no preparation. A wood-fired tub is slower and more deliberate. Lighting the stove, feeding the fire and waiting for the water to warm becomes part of the evening. There is no pump noise, and the water feels still and deep. Some owners pair a wood-fired tub with a cold plunge or an outdoor sauna to create a full outdoor bathing area.
Which Should You Choose?
An electric hot tub is likely the better fit if
- You want to soak often, on short notice, with minimal effort.
- Jets and precise temperature control matter to you.
- You have convenient access to electrical service near the tub site.
A wood-fired hot tub is likely the better fit if
- You soak a few times a week and enjoy the ritual of heating it.
- The site is far from power, or adding a 240V circuit is costly.
- You prefer a simple, quiet tub with few mechanical parts.
- You have access to dry firewood.
FAQ
How long does a wood-fired hot tub take to heat?
Commonly about 2 to 4 hours from cool water, depending on tub volume, starting water temperature, the stove design and how dry the wood is. Using a cover while heating helps.
Is a wood-fired hot tub cheaper to run than an electric one?
It can be, especially if you have your own firewood. With purchased wood, estimated monthly costs can be similar to an electric tub. The main trade is time and effort versus constant readiness.
Do wood-fired hot tubs need chemicals?
If you drain and refill frequently, many owners use little or none. If you keep the water for longer periods, a sanitizer and a cover are recommended, just as with any shared water.
What electrical service does an electric hot tub need?
Most full-size models need a dedicated 240V GFCI-protected circuit, commonly 40 to 50 amps. Smaller 120V models plug into a standard outlet but heat much more slowly. A licensed electrician should confirm the requirements.
Can you use a wood-fired hot tub in winter?
Yes, and many owners enjoy it most in cold weather. Heat-up takes longer when the water and air are cold, and you should drain the tub or protect it from freezing when it is not in use for extended periods.
If the ritual of a wood-fired soak appeals to you, you can explore sizes and stove designs in our wood-fired hot tub collection. Our team can help you think through placement, capacity and firewood needs; reach out through the contact page.