Hot tub vs sauna: how they differ at home

How each one works

A hot tub, whether inflatable or hard shell, heats water with an electric heater and circulates it through a filter. Bubbles or jets move the water around you. Most inflatables let you set up to 40 °C, the usual maker maximum.

A home sauna is a timber room or cabin heated by an electric or wood burning stove. Air temperatures are much higher than hot tub water, and some people pour water on the stones for bursts of steam. There is no water to treat, but the room must be ventilated and dried out after use.

Side by side

The table describes typical home set-ups. Commercial units and large hard shell tubs differ.

Space and installation

An inflatable hot tub needs a flat, firm base that can take a heavy load when filled, plus room to walk round it and lift the cover. It can be set up in an afternoon and packed away later. See our page on where to put an inflatable hot tub for base ideas.

A sauna is a building project. Outdoor barrel and cabin saunas need a solid base, weatherproofing and a heater fitted to the maker's instructions. Indoor saunas need ventilation and a suitable electrical supply. Most electric sauna heaters need a dedicated circuit, which is a job for a qualified electrician.

Note:Hot tubs combine water and mains electricity. Use a weatherproof outdoor socket protected by an RCD, follow the maker's manual, and have any new circuit or socket fitted by a qualified electrician.

Upkeep through the year

A hot tub asks for regular attention. You test the water a few times a week, keep the sanitiser and pH in range, rinse the filter and change the water every few months. In winter the heater works harder, and an inflatable may need a thermal cover or extra insulation.

A sauna has no water to keep in balance. You wipe or scrub the benches, leave the door open to dry the timber and check the heater and stones occasionally. Winter use is straightforward because the room is heated from cold each time.

See hot tubs for winter use →

Social use and routine

Hot tubs tend to be social. Four to six people can sit together, chat and stay for a while. That is why many families choose one. A sauna session is usually shorter and quieter. If you plan to use it alone or as a couple, a small sauna can be very appealing.

Think about who will use it and when. A tub that sits ready under its cover suits spontaneous use; a sauna needs time to heat, but nothing in between.

Which suits you?

• You want a social outdoor soak for the family: a 4 to 6 person inflatable hot tub. See our 6 to 8 person guide.
• You want low upkeep and short quiet sessions: a sauna.
• You rent or may move: an inflatable tub, as it packs away.
• You have no outdoor socket: either needs electrical work, so get an electrician's quote first.

Frequently asked questions

Is a hot tub or sauna easier to maintain? A sauna, because there is no water to test and treat. A hot tub needs regular water testing, sanitiser and filter care.

Can you have a hot tub and a sauna together? Yes, and some gardens have both. Plan the electrical supply carefully, as running both heaters needs suitable circuits; ask an electrician.

Which uses more electricity? It depends on the heater ratings and how often each is used. Check the kW rating of each heater and estimate hours of use to compare in kWh.

Should I talk to a doctor before using either? If you have a medical condition or are pregnant, check with a GP before using a hot tub or sauna, and always follow the maker's safety guidance.