How Much Electric Do Hot Tubs Use

Hot tubs have become increasingly popular in UK homes, offering relaxation, hydrotherapy benefits, and a touch of luxury in the garden. However, one of the most common concerns for homeowners and landlords considering a hot tub installation is how much electricity they use and what this means for running costs. Unlike smaller appliances, hot tubs require a significant amount of power to heat the water and run pumps, which makes them different from many other household electrical items. Understanding their energy consumption is important for both budgeting and ensuring the electrical supply to the property is safe and compliant with UK regulations.

How Hot Tubs Use Electricity

Hot tubs consume electricity in two main ways. The first is through heating the water, which requires a heater element to raise the temperature from cold to a comfortable bathing level, usually between 37 and 40 degrees Celsius. The second is through the operation of pumps, lights, and jets that circulate the water and create the spa effect. Depending on the type of hot tub, additional energy may also be required for features such as filtration cycles, built-in sound systems, or integrated lighting. The balance between these functions determines how much electricity a hot tub uses on a daily or monthly basis.

Power Ratings and Consumption

Most hot tubs designed for home use have heaters rated between 2 kW and 3 kW. This means that running the heater for one hour will consume between 2 and 3 kilowatt-hours (kWh) of electricity. The initial heating cycle, when the water is first brought up to temperature, is the most energy intensive stage. Depending on the size of the tub and the efficiency of the insulation, this can take between 12 and 48 hours. Once the water reaches the desired temperature, the heater only needs to maintain it, switching on and off automatically through a thermostat. This maintenance phase uses less electricity than the initial heating cycle but still contributes to ongoing consumption.

Daily and Monthly Usage Estimates

On average, a well-insulated hot tub may use between 6 and 10 kWh of electricity per day once the water is up to temperature. This translates to approximately 180 to 300 kWh per month. At an electricity cost of 30 pence per kWh, this equates to between £54 and £90 in running costs each month. Poorly insulated or older hot tubs can use significantly more, sometimes exceeding 500 kWh per month, which would cost upwards of £150. The size of the tub, frequency of use, ambient temperature, and insulation quality all play a large role in determining the final figure.

Impact of Location and Insulation

Where the hot tub is located makes a big difference to electricity consumption. An outdoor hot tub exposed to wind and cold air will lose heat more quickly than one housed in a sheltered or insulated enclosure. Good-quality covers and insulation around the tub shell and pipework can drastically reduce heat loss, lowering the amount of electricity needed to maintain water temperature. Modern hot tubs are usually designed with energy efficiency in mind, but older or budget models may not hold heat as effectively, increasing consumption and costs.

Pumps and Circulation Systems

Alongside the heater, hot tubs also rely on pumps to circulate water and power the jets. A typical circulation pump may be rated at around 200 to 300 watts, while larger jet pumps can range from 1 kW to 2.5 kW depending on the model. These do not run continuously, but when in use they can add noticeably to the overall electricity consumption. The number of pumps and how long they are used each day will affect the total energy demand. Some hot tubs also run filtration cycles automatically, which ensures clean water but adds to overall running hours for the pumps.

Electrical Safety Considerations

Installing a hot tub in the UK requires proper electrical planning to comply with Part P of the Building Regulations and the BS 7671 Wiring Regulations. Hot tubs usually require a dedicated supply from the consumer unit, protected by a residual current device (RCD) to prevent electric shock risks in wet environments. The supply rating is typically 13 amps for smaller plug-and-play models and up to 32 or 40 amps for larger tubs. For this reason, a qualified electrician should always be involved in the installation to ensure both safety and compliance with regulations.

How to Reduce Electricity Usage

While hot tubs are inherently energy intensive, there are practical steps homeowners can take to reduce consumption. Using a high-quality insulated cover when the tub is not in use prevents unnecessary heat loss. Setting the temperature a degree or two lower can also have a noticeable impact on daily consumption. Running filtration and cleaning cycles during off-peak hours on a smart tariff can reduce costs without affecting performance. Regular maintenance, including checking seals and insulation, ensures the system operates efficiently and does not waste energy.

Comparing Hot Tubs to Other Household Appliances

To put hot tub electricity use into perspective, a typical electric oven may use around 2 to 3 kWh per hour of cooking. A tumble dryer can consume 4 to 5 kWh per cycle. While these appliances are only used for short periods, a hot tub runs regularly to maintain water temperature, meaning its electricity use accumulates over time. For households with high electricity costs, the impact on energy bills can be substantial, which is why it is important to consider efficiency features before purchase.

Conclusion

Hot tubs use a significant amount of electricity compared to most household appliances, mainly due to the energy required to heat and maintain the water at a comfortable temperature. The exact consumption depends on the size of the tub, the quality of its insulation, the number of pumps, and how often it is used. With good insulation, efficient controls, and sensible usage habits, electricity consumption can be managed effectively, but homeowners should still expect hot tubs to have a noticeable impact on their monthly energy bills. For those considering installation, it is also vital to ensure that the electrical supply is designed and installed safely by a qualified professional.