How do I calculate a hot tub running cost?

Multiply average daily electricity use in kWh by the electricity unit rate in pounds. Add water-care, filter, service and repair allowances separately.

Does the calculator include the standing charge?

No. A household pays the electricity standing charge whether or not it owns a hot tub, so the calculator excludes it from the incremental hot tub estimate.

Why can the actual cost differ?

Weather, water temperature, insulation, cover fit, filtration, bathing, reheating and the local electricity tariff all affect the result.

Free UK calculator

Hot tub running-cost calculator.

Turn a daily energy-use figure into a cost you can compare. Your tariff, consumption and water-care allowance stay visible and editable.

Built and reviewed by Adam Brown

Your assumptions

Build your estimate

Electricity unit rateUse the pence-per-kWh figure from your tariff.p/kWh

Pre-filled with Ofgem’s GB Direct Debit average for 1 July to 30 September 2026. Your tariff and region may differ.

Average electricity use per dayUse a manufacturer figure or, preferably, your own measured average.kWh/dayWater-care and filter budgetOptional monthly amount for chemicals, filters and routine consumables.£/month

Calculated estimate

Your running-cost picture

Estimated monthly total£54.71Electricity plus your water-care allowance

Electricity per day£1.31

Electricity per month£39.71

Electricity per year£476.51

Total per year£656.51

If consumption is 25% lower or higher£44.78–£64.64 a month

This is arithmetic, not a performance claim. Weather, water temperature, cover fit, insulation, filtration, bathing and reheating all change consumption. Standing charges are excluded because you pay them for the property regardless of the hot tub.

Calculation method

Build the estimate from figures you can check.

The calculator does not assign one monthly figure to every hot tub. It keeps the consumption, tariff and water-care allowance separate so you can update each one.

Daily electricity costdaily kWh × unit rate ÷ 100For example, 5 kWh × 26.11p = £1.31 per day.

Use a measured week

Include normal bathing, filtration and reheating, then divide the recorded kWh by the number of days.

Use your tariff

Copy the electricity unit rate from your bill. Do not add the household standing charge again.

Keep care separate

Add chemicals and filters as a visible allowance instead of hiding them inside an energy claim.

How to get a more useful answer

The strongest input is measured kWh over a representative week, including normal bathing and filtration. A manufacturer estimate can be a starting point, but ask what air temperature, water temperature, cover use and test standard sit behind it.

What the calculator includes

Electricity is calculated as daily kWh × your pence-per-kWh rate. The monthly figure uses 365 ÷ 12 days. You can add a separate monthly allowance for chemicals, filters and routine consumables. It excludes finance, servicing, repairs, water and the household standing charge.

Electricity-rate source

The starting rate is Ofgem’s average Direct Debit electricity unit rate for Great Britain from 1 July to 30 September 2026. It includes VAT, but regional rates and individual tariffs differ. Check the official Ofgem table .

Questions about hot tub running costs

Should I trust a cost-per-day claim?

Use it as a starting point only when the company states the model, test conditions, consumption and electricity rate behind it.

Should the hot tub stay heated?

The useful comparison is measured consumption under your expected routine. Reheating from cold, frost protection and filtration can change the result, so follow the model instructions.

What is not included?

The result excludes finance, water, routine servicing, repairs and eventual cover replacement. Add those as separate annual lines.