Hot Tub Running Cost Calculator UK
Considering a hot tub or wondering how much your existing one costs to run? Our free UK hot tub running cost calculator estimates your daily, weekly, monthly and annual electricity costs based on your heater wattage, pump power, running hours and the current Ofgem electricity rate. Just enter your hot tub's specifications and see the results instantly.
Hot tubs are one of the most energy-intensive items you can own. A typical inflatable hot tub costs £30 to £50 per month to run, while a hard-shell spa with a more powerful heater can cost £40 to £70 per month or more. The biggest factor is how many hours per day the heater runs to maintain temperature, which depends on insulation quality, outdoor temperature and how often you use the tub. This calculator lets you experiment with different settings to find the most cost-effective way to enjoy your hot tub without bill shock.
How Much Does a Hot Tub Really Cost to Run?
The running cost of a hot tub depends on three main factors: the heater wattage, how many hours per day the heater cycles on, and the efficiency of the tub's insulation. A well-insulated hard-shell hot tub with a 2kW heater that cycles for 4 hours a day costs around £0.98 per day at the Ofgem cap rate of 24.5p per kWh. An inflatable tub with poor insulation may need the heater on for 8 to 12 hours, pushing daily costs above £2.50.
Pump and filtration costs add to the total. Most hot tubs run a circulation pump for 4 to 12 hours per day, drawing 200W to 1,500W depending on the model. The total annual running cost for a typical hot tub ranges from £400 to £900, making it one of the most expensive household items to operate. Check the latest electricity rates on the Ofgem consumer information page.
Tips to Keep Hot Tub Costs Down
The single most effective step is using a high-quality, well-fitting thermal cover whenever the tub is not in use. Heat loss from the water surface accounts for the majority of energy waste. A floating thermal blanket under the main cover adds an extra layer of insulation and can reduce heating costs by 10 to 15 percent.
Lowering the set temperature by just 1 to 2 degrees makes a measurable difference. If you are on a time-of-use tariff like Economy 7, programming the heater to run overnight at cheaper rates can halve the electricity cost. For a broader view of your home electricity spending, use our electricity cost calculator, or see how much other high-draw appliances cost with the appliance running cost calculator.
Inflatable vs Hard-Shell Hot Tubs
Inflatable hot tubs are popular due to their low upfront cost of £300 to £700, but they lack the insulation of hard-shell models. This means the heater runs far more often to maintain temperature, especially in cooler months. A hard-shell tub costing £3,000 to £8,000 typically saves £200 to £400 per year in electricity, often paying back the price difference within a few years through lower running costs alone.
Hard shell hot tubs are significantly cheaper to run despite costing more to buy. An inflatable typically costs 50–100% more in electricity per year. The price difference is usually recouped within two to three years.
Always use a well-fitting thermal cover. Lower the temperature by 1–2°C, add a floating blanket, reduce filtration times in warmer months, and consider heating during off-peak hours on an Economy 7 tariff.
For hard shell tubs with good insulation, maintaining constant temperature is generally more efficient. For inflatable tubs, heating on demand may save money if you use it fewer than three times a week.
Yes. Winter running costs can be 40–60% higher than summer due to the larger temperature difference. Using a quality cover, sheltered position and extra insulation all help reduce the increase.
This calculator provides estimates for guidance only. Actual costs depend on your hot tub model, insulation, usage patterns and electricity tariff. This is not financial, legal or professional advice. For current electricity rates, visit Ofgem.