Spring is on the horizon, but that doesn’t mean we’re free from the winter chill just yet. Here’s everything you need to know about the cost of running an electric heater.
It’s important to keep your home warm year round – if not for your own health and comfort (which we think is more than enough reason) then to prevent your house from encountering mould, frozen pipes, cracked plaster and other damages you’ll be forced to deal with later down the line.
More importantly, the NHS warns that exposure to cold weather can be harmful to your body, especially if you’re over the age of 65, as it can weaken the immune system, increase blood pressure, thicken the blood and lower body temperature and even increase your risk of developing high blood pressure, heart attacks, strokes and chest infections. For this reason, the UK health service recommends heating your home to at least 18°C.
It’s all well and good being told you should heat your home, but what about the cost? We’ve compiled this guide to explain everything you need to know about electric heaters, including how much electricity they use and how much they cost to run.
Do electric heaters use a lot of electricity?
Electric heaters do require a lot of electricity and are considerably more expensive to run than central heating, via a gas boiler or heat pump.
According to a research paper published by Ofcom in 2015, “In general terms, electric heating tends to be more expensive than heating with mains gas, in particular when using direct-acting electric room heaters. Heating costs however depend on a range of factors such as size and insulation of property, type of energy tariff, heating needs and ability to shift and manage energy use”.
This doesn’t mean its always a bad idea to opt for electric heating. If you’re only looking to heat one room and your home is poorly insulated or there’s no radiator in that room, an electric heater can be a quick way to warm yourself up for an hour or so.
Electric heaters are also useful in rooms where you can’t easily extend your central heating, such as to a garden office or other outbuilding.
However, gas remains significantly cheaper in general (by around 3x), meaning it’s still considered a better money saver in the long run. This is especially true if you have a newer, more efficient boiler as opposed to an old outdated one, or have upgrade to a heat pump. Central heating is also the better choice for heating up large rooms and keeping them warm for longer periods at a time.
How much does it cost to run an electric heater?
The exact cost to run an electric heater will depend on your energy supplier, rates and the amount of energy you use.
The most recent energy cap (January 1 to March 31 2025) has users spending an average of 24.86p per kWh including VAT, says Ofgem. According to UK appliance brand Morris Direct, the typical power consumption for running different electric heaters is as follows:
- Convection heater: 2kW
- Radiant heater: 1.2kW
- Fan heater: 1.5kW
- Panel heater: 0.25kW
- Tube heaters: 0.1kW
To figure out how much it costs to run a specific type of electric heater, use the following calculation: power rating of heater (kW) x duration (hours) x 24.86 (cost per kWh). For example, the price to run a convection heater for one hour will be around 49.72p (2 x 1 x 24.86).
However, electric heaters won’t need to run constantly, as once your room is at the right temperature, you can turn them off. It’s best to buy a heater with an integrated thermostat, so that it can turn off when the target temperature is reached, and turn on again when the room cools down.
How long a heater has to run for depends on the size of the heater, the target temperature, how well insulated your home is and the outside temperature. When we test electric heaters we generally find that they take between 10 and 20 minutes, depending on their power, to raise a room from around 14°C to a comfortable 18°C.
Over a typical eight-hour working day, an electric heater will most likely need to run for a couple of hours maximum to heat a room and maintain the temperature.
For heating a single room, an electric heater may be cheaper than central heating to heat the entire house. However, if you have individual room control via a smart system, such as Tado X, then central heating will be cheaper to run. For heating more than one room, central heating is the cheaper option.
What electric heaters are most efficient?
As our Home Technology Editor, David Ludlow mentions in our guide to the best electric heaters, all electric heaters are nearly 100% efficient, which means that input electricity is all converted to heat. While a high-power heater will warm a room faster than a low-power one, all will use the same amount of power to raise the temperature of a room to the target temperature.
It’s important to buy a heater that’s powerful enough for the room you want to heat, and most heaters are rated for a maximum room size. If you buy an underpowered heater, your room won’t reach the right temperature.
One of the best ways to prevent overspending on energy is to opt for an electric heater with a built-in thermostat. These heaters can automatically shut themselves off once your room has reached your desired temperature, ensuring you don’t spend a penny more than you need to.
Are oil heaters expensive to run?
Oil heaters cost more than electric heaters up front. With these heaters, electricity heats the oil, which then outputs heat. These heaters are slow to heat up but continue to output heat once they stop drawing electricity, similar to a water-filled radiator. Oil heaters cost the same amount to run as other electric heaters, but the slow cool-down can make a room feel more comfortable; with a fan or convection heater, a room can start to feel cold as soon as the heaters are off.
