How Much Does a Hot Tub Cost to Run in the UK?

It is the question every prospective buyer asks, and the one retailers are vaguest about. The honest answer is that a hot tub costs £30 to £90 a month to run in the UK. A well-insulated tub used a few times a week sits at the bottom of that range; an inflatable left running through January sits at the top.

Below is the full cost table at the current rate, what actually drives the number, and the changes that make the biggest difference to your bill.

Hot tub running costs at 26.32p per kWh

Most modern hot tubs use 3–6 kWh of electricity a day to hold the water at temperature under a cover. Poorly insulated and inflatable tubs in cold weather can use 10 kWh or more.

Illustrative estimates at the Ofgem price cap rate of 26.32p per kWh (1 October – 31 December 2026); a month is taken as 30.4 days. Your own cost depends on your tariff, your tub and how you use it.

Electricity is only part of the story

Running costs go beyond the meter reading. A realistic all-in monthly budget for hot tub ownership in the UK looks something like this:

• Electricity: £25–£90 per month. The single biggest cost, and the one most affected by insulation and season.
• Chemicals: £20–£45 per month. Chlorine or bromine, pH balancers, shock treatment and test strips.
• Filters: £40–£120 per year. Most tubs need filter cartridges replaced every 12 months, sometimes more often with heavy use.
• Servicing: £150–£200 per year. An annual professional service, or £25–£50 a month on a service plan.
• Water: £10–£30 per refill. Most owners drain and refill every three to four months.

Add it all up and a sensible all-in figure for most UK households is £55 to £150 per month.

What actually drives the cost

1. Insulation quality — the biggest factor by far

This is where cheap tubs get expensive. Full-foam insulation, where the entire cabinet cavity is filled with expanding foam, retains heat dramatically better than perimeter insulation, which only lines the outer walls. Full-foam models typically cut heating costs by 25–35% compared with perimeter-insulated equivalents.

2. Your cover

Up to 75–90% of a hot tub's heat loss happens through the water surface. A thick, tapered, well-fitting cover in good condition is the cheapest efficiency upgrade you can make. If your cover is waterlogged, sagging in the middle, or no longer seals at the edges, replacing it will pay for itself surprisingly quickly.

3. Hard-shell versus inflatable

Inflatable tubs have a much lower purchase price, but they are considerably less efficient to run. In cold weather an inflatable can cost 40–60% more per month than a well-insulated rigid tub, sometimes topping £150 in the depths of winter. If you plan to use your tub year-round, a hard-shell model is usually cheaper over its lifetime despite the higher upfront cost.

Every tub in our best hot tubs UK roundup is an inflatable, so it is worth knowing what to compare. Wall construction and insulation claims vary: the Lay-Z-Spa Santorini HydroJet Pro is sold with Lay-Z-Spa's EnergySense insulation, which the manufacturer says is 40% more efficient, while the Nordivale lists an 1,800W heater. At 26.32p per kWh, an 1,800W heater costs about 47p for every hour it is actively heating, so the less often it has to fire, the lower your bill. If you are choosing between the two biggest brands, our Lay-Z-Spa vs CleverSpa comparison shows how thicker walls translate into lower winter costs.

4. Season and location

Expect to pay roughly £20–£40 a month in summer and £40–£150 in winter. An exposed, windy garden loses heat faster than a sheltered corner — a fence, hedge or gazebo genuinely reduces your bill. If you're weighing up whether to keep yours running through the colder months or drain it entirely, our guide to whether to leave your hot tub empty over winter covers the pros, cons and step-by-step draining instructions.

5. Your electricity tariff

If you can shift heating cycles to off-peak hours on an Economy 7 or agile tariff, you can knock 20–30% off the annual electricity cost without changing anything about the tub itself.

Should you switch it off between uses?

No — and this is the mistake that costs people the most money. It feels intuitive that turning the tub off when you're not using it must save energy, but reheating a full tub from cold takes a large, sustained power draw over many hours. Raising 1,000 litres of water by 25°C needs about 29 kWh before any heat is lost — roughly £7.65 at 26.32p per kWh, and more on a cold, windy day. Maintaining a steady temperature under a good cover uses far less energy overall.

The exception is a genuinely long absence. If you're away for several weeks in mid-summer, draining or shutting down can make sense. For anything shorter, leave it running.

Seven ways to cut your running costs

1. Upgrade a tired cover. The single highest-impact fix if your existing one is worn.
2. Add a floating thermal blanket. A £20–£40 accessory that sits directly on the water under the cover and noticeably reduces evaporation losses.
3. Drop the temperature by 1–2°C. Going from 40°C to 38°C is barely noticeable in the water but meaningfully cheaper.
4. Shelter the tub. A fence panel, hedge or gazebo on the windward side reduces convective heat loss.
5. Clean your filters monthly. Clogged filters make the pump work harder and reduce circulation efficiency.
6. Move heating to off-peak hours. Use the tub's built-in scheduling with an Economy 7 or agile tariff.
7. Consider an air-source heat pump. A significant upfront cost, but heat pumps can cut heating electricity by 70–80% and pay back over a few years if you use the tub heavily.

Is a hot tub worth the running cost?

At roughly £36 a month in electricity for a typical well-insulated tub, a hot tub costs about the same as a mid-range gym membership — for something you can use every day in your own garden.

The catch is buying the right tub in the first place. A poorly insulated model costs more every month for as long as you own it, and the saving on the purchase price can disappear within a couple of years. It is also worth factoring in how long inflatable hot tubs actually last, and if you are still deciding whether to buy at all, read our honest verdict on whether inflatable hot tubs are worth it. Our UK hot tub buying guide covers sizing, electrics and water care, and how we review explains how we score each tub.

Frequently asked questions

How much does a hot tub cost to run per day in the UK?

At the Ofgem price cap rate of 26.32p per kWh (1 October – 31 December 2026), a well-insulated hot tub using 3–6 kWh a day costs about 79p to £1.58 a day. An inflatable tub in winter using around 10 kWh costs about £2.63 a day.

How much does it cost to heat a hot tub from cold?

Raising 1,000 litres of water by 25°C takes about 29 kWh, which is roughly £7.65 at 26.32p per kWh before heat losses. In cold or windy weather the real figure is higher, which is why switching off between uses rarely saves money.

Is it cheaper to leave a hot tub on all the time?

For regular use, yes. Holding the water at temperature under a good cover uses less energy than repeatedly reheating it from cold. Shutting down only makes sense for an absence of several weeks, ideally in summer.

Do inflatable hot tubs cost more to run?

Usually. In cold weather an inflatable can cost 40–60% more a month than a well-insulated hard-shell tub, because its walls and lid hold heat less well. A thermal cover and floating blanket close a lot of that gap.

Will hot tub running costs change in January?

Possibly. Ofgem sets the price cap every three months, and the next period starts on 1 January 2027. To recalculate, multiply your tub's daily kWh by the new unit rate shown on your bill.

Work out what your hot tub will cost to run

The figures above are averages. To get your own number, take three minutes:

1. Find your unit rate. It is on your latest electricity bill or app, shown in pence per kWh. If you are on a standard variable tariff, it will be close to 26.32p until 31 December 2026.
2. Estimate your daily kWh. Use 3 kWh for an insulated tub in summer, 4.5 kWh as a year-round average, and 6–10 kWh for winter or an inflatable. A smart plug rated for the load, or your tub's own energy display, gives you a real reading after a week.
3. Multiply. Daily kWh × unit rate × 30.4 = your monthly cost. For example, 5 kWh × 26.32p × 30.4 = about £40 a month.

If that number is higher than you would like, the specification to compare is insulation and cover quality. Compare the best hot tubs in the UK with those points in mind before you buy.