Are Hot Tubs Expensive to Run?

Are Hot Tubs Expensive to Run?

Whether you’re in the market for a Hot Tub or you already own one you may be wondering how much it is to run a Hot Tub with the current energy prices.

Whilst we can estimate that it costs around £3 a day to run one of our average family Hot Tubs, (less than a latte from your local coffee shop) the amount of energy consumption can differ when you factor in the different variables.

These variables include the size of the Hot Tub, the temperature outside, how often you may use the Hot Tub, how long it is used for, age and quality of the Hot Tub cover, the temperature of the water and of course your electrical tariff.

Electrical Components

The electrical components used in your Hot Tub, such as the heater can influence the energy efficiency. Although heaters can come with different kW ratings, this won’t directly affect your energy usage. If a heater has a larger kW rating this will heat the water faster however, it won’t take as long to do so. For instance, a 3kW heater fitted to our average size family Hot Tub can take around an hour to raise the temperature by 1° whereas a 1.5kW heater can take around 2 hours. It’s important to bear in mind that in colder temperatures the heater will need to work harder to maintain temperature.

Frequency of Use

Frequency of use will also play a huge part in the running cost of your Hot Tub. Those who enjoy their Hot Tub 3 or 4 times a week can expect higher charges than those who may use theirs once a week.

We are often asked if a Hot Tub can be switched off when not in use, this is something we would not recommend. Once at the desired temperature you will save energy (and money) leaving the Hot Tub on. If switched off, it will take a lot more energy to reheat the spa back to the temperature target. However, if you are going away or not using your hot tub for a longer period, we would normally recommend turning the temperature down or placing the spa in rest mode.

Number of Bathers

Unless you desire a larger Hot Tub, it may be more energy efficient to choose a model with the average number of regular bathers. This is down to the fact that if a Hot Tub has a large volume of water, it will require more energy to keep that water warm. We recommend choosing a Hot Tub with at least 250 litres of water capacity per person.

Hot Tub Maintenance

Most Hot Tub owners choose to have their spa serviced at least once a year. Like a car, your Hot Tub should be kept in optimum condition in order to perform at its best. When your Hot Tub has a service, not only is the spa cleaned, a full inspection is completed to ensure all electrical components are working as they should. The Hot Tub is also checked for any O’ring leaks which can be difficult for the inexperienced eye to spot. Preventing any component failures and repairing any leaks can keep your Hot Tub working as energy efficient as possible.

Ensuring your filters are free from any limescale or blockages will improve the lifespan of your Hot Tub. Blocked filters can affect the circulation which puts strain on your motor and heating elements. We advise that your filters are cleaned at least once a week and replaced annually.

Replacing your filters and purchasing chemicals can add around £250-£350 to the running costs. Chemical costs will vary depending on the system you choose (such as chlorine, bromine, or salt system.) It is most cost effective to buy larger quantities or buy in bulk if you can.


Tips for Saving Money

  1. Don’t buy cheap! If you’re in the Hot Tub market buying a cheaper spa will often cost far more money in the long run. When searching for the right Hot Tub for you, consider purchasing a premium model. These models are likely to include higher insulation, an energy efficient heater as well as many other benefits. Insulation is arguably the most important factor for an energy saving hot tub. This is because insulation creates a barrier between the shell's surface and the temperature outside, which reduces the amount of work your spa must do. Less work means less energy spent and generally a lower energy bill.
  1. Invest in a thick, insulated cover! Hot Tubs can lose 60% or more of its heat through the surface, therefore you need to ensure your Hot Tub cover is fitted correctly. If not sealed correctly this can make your energy consumption soar. You want to check that your cover is well insulated as this will improve overall heat retention. The ideal Hot Tub cover is a minimum of 4 inches thick in the middle and 2 inches at the front and back. If your cover is starting to bow or has become water logged this means it is time for a replacement. Our EZ Weather-Shield covers are equipped with bi-fold insulation finished in a luxury oxford material and have a thickness of 4 inches.
  1. Buy a floating blanket A laminated foam blanket is a relatively low-cost investment for your Hot Tub as it will quickly pay for itself by saving running costs. A floating blanket can reduce up to 95% heat loss due to evaporation, adding a further layer of insulation when used under your spa cover. This provides a barrier between the spa water and the underside of the spa cover. Protecting the underside of the cover from the effects of chemicals and excess moisture will prevent any water logging, one of the main causes of cover failure.
  1. Close those valves! Closing diverter valves is a great way to ensure no heat is lost as open jets can introduce cold air to the Hot Tub.
  1. Keep chemicals correct! Maintaining correct water chemistry can also save you money. A Hot Tubs pH is particularly important in this case as acidic water can cause corrosion to the heater. We recommend keeping the pH between 7.2 and 7.8.
  1. Keep the Hot Tub switched on! Although counterintuitive, your Hot Tub may have to work harder to heat the water once switched off. If a Hot Tub is well insulated, sustaining a steady temperature will be more cost effective. This means you should leave your hot tub running if you can, unless you are not intending to use it for a period of time.
  1. Fit an Air Source Heat Pump! Air Source Heat Pumps are one of the most efficient methods of heating systems available and can save up to 80% in heating cost. It is important to select the right size heat pump for your Hot Tub, key factors will depend on volume of water, amount of use (part or all year), water flow rate and cost. Most Hot Tubs will have a 3kW heater as standard so, as a minimum do not use less than a 3kW. It is a good idea to select a larger rating unit that fits into your budget. The bigger the heat pump the quicker the unit will heat the water but it is important to ensure that here is adequate water flow through the heat pump.

         Other important factors with heat pumps;
  • Only one air source heat pump (or other renewable heat source) would be classed as permitted development, additional air source heat pumps at the same property will require planning permission.
  • All parts of the air source heat pump must be at least one metre from the property boundary, or further dependant on noise or the direction of the cold air discharge.
  • Permitted development rights do not apply for installations within the curtilage of a Listed Building or on land within a Conservation Area.
  • Air source heat pump must not be installed on a wall or roof which fronts a highway.
  • Any heat pump must meet BS EN Standards.
  1. Check your electrical tariff! – Most electricity providers will offer an off-peak lower cost energy tariff. The off -peak will vary by provider but can be between 10pm and 8am.Ask your supplier if the off-peak tariff is available, it will probably be worth opting in. The rate can be as much as 50% less that the standard daily tariff!
  1. Off-peak spa settings – if you have the off-peak tariff available you will need to reprogramme your spa controls so that it only filters and heats during the hours the tariff is available. Changing the setting is very straight forward and will require setting up the filter cycles through the spa top side panel. With spa models that do not have an internal clock you might need to set up the filter cycles by turning off the spa and on again when the off-peak tariff starts. Call our service team if you need help.

It should be noted that if you have a heat pump, the off-peak tariff will benefit only if the heat pump is able to harvest heat from the cooler ambient temperature at night. Most Heat pumps need to run constantly.

Overall, the benefits of using a Hot Tub can provide value to both your physical and mental health, improve sleep quality and boost quality time spent with friends and family. If you take all these factors into account the answer is Hot Tubs are not expensive to run. Based on the use of an average sized Hot Tub used 3 or 4 times a week for at least half an hour, the cost would total around £1095 per year.

If you have any questions or require more information, we will be happy to assist. Call 01980 611555 or email 

Prices correct at time of posting. October 2022

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