How Much Electricity Does a Hot Tub Use

Hot tubs are often associated with comfort and luxury, but many UK homeowners also view them as an investment in their outdoor living space. While they provide relaxation and health benefits, one of the most common questions people ask before buying or running a hot tub is how much electricity it will use. Understanding energy consumption is important, not only for managing running costs but also for ensuring that the installation is safe and compliant with UK electrical regulations.

Understanding Hot Tub Power Requirements

A hot tub uses electricity to power several systems, including the water heater, pumps, and in many cases lighting and entertainment features. The heater is by far the largest consumer of energy, as it maintains the water at a comfortable temperature. Most domestic hot tubs in the UK require a dedicated power supply and are usually rated between 2 kilowatts and 3 kilowatts for smaller plug-and-play models, and up to 7 kilowatts for larger hard-wired installations. This means that the electrical demand of a hot tub can vary widely depending on the model and how it is used.

Daily and Monthly Electricity Use

The energy use of a hot tub is not constant and depends on several factors, such as the size of the unit, the heater rating, and how well insulated it is. A typical hot tub may use between 1.5 and 2.5 kilowatt hours of electricity per hour when the heater is running. However, once the water reaches the desired temperature, the system only needs to top up heat occasionally, meaning the actual daily consumption is lower. On average, a well-maintained hot tub used a few times a week may add between £20 and £40 to a monthly electricity bill at current UK energy prices.

Factors That Affect Hot Tub Energy Consumption

Several factors influence how much electricity a hot tub will use. Location is important, as an outdoor hot tub in a cold or exposed area will lose more heat than one in a sheltered position. Insulation plays a major role, with models that have full-foam insulation retaining heat much more effectively than cheaper alternatives with minimal lining. The frequency of use also matters, since opening the lid and using the jets allows heat to escape, increasing the amount of work the heater must do to bring the water back to temperature. Water temperature itself is another key factor, as setting the thermostat just a few degrees lower can result in noticeable savings over time.

Comparing Plug-and-Play and Hard-Wired Hot Tubs

Smaller plug-and-play hot tubs, which can be connected to a standard 13-amp socket, generally use less electricity because they have smaller heaters and pumps. They take longer to heat up initially, but once warm, their running costs are relatively modest. Larger hard-wired models that require a 32-amp or 40-amp supply heat the water much faster and provide stronger jet performance, but they inevitably consume more electricity. For households with larger families or those who want frequent use, the higher energy demand may be worth the trade-off for performance.

Energy Efficiency and Running Costs

Modern hot tubs are designed with efficiency in mind, and many feature advanced controls and eco modes that reduce energy use when the tub is not in active use. A well-insulated hot tub with a high-quality cover will cost less to run because it loses less heat to the surrounding air. Running the hot tub at a lower temperature when not in use and increasing it only before use can also reduce electricity consumption. Some owners choose to use their hot tub seasonally to avoid higher winter heating costs, although efficient insulation allows year-round use without excessive expense.

Installation and Electrical Safety

Installing a hot tub is not just a matter of plugging it in. Larger models require a dedicated electrical circuit and consumer unit connection, installed by a qualified electrician. In the UK, this work is subject to Part P of the Building Regulations, which means it must either be notified to local building control or carried out by a registered electrician who can self-certify the installation. Compliance with the current edition of the Wiring Regulations (BS 7671) is essential, and protective devices such as RCDs are required to reduce the risk of electric shock. These safety considerations are as important as the running costs and should not be overlooked.

Practical Tips to Keep Costs Down

For homeowners concerned about electricity bills, there are several steps that can be taken to reduce hot tub running costs. Investing in a high-quality, well-insulated cover prevents heat loss when the tub is not in use. Regular maintenance of pumps, filters, and heaters ensures that the system operates efficiently and does not waste energy. Placing the hot tub in a sheltered location, such as under a pergola or within a garden room, reduces exposure to wind and cold air, which would otherwise draw heat from the water. Finally, setting a slightly lower water temperature can make a surprising difference to overall energy consumption without sacrificing comfort.

Conclusion

The electricity use of a hot tub varies depending on its size, design, insulation, and frequency of use. Smaller models may only add a modest amount to a monthly electricity bill, while larger, more powerful tubs can cost significantly more to run. However, with good insulation, regular maintenance, and sensible use, running costs can be kept under control. Homeowners considering installing a hot tub should factor in not only the purchase price but also the long-term energy demand, as this will affect the overall affordability. When installed correctly by a qualified electrician and used efficiently, a hot tub can provide relaxation and enjoyment without causing excessive energy bills.