How much does an electric heater cost to run?
A 2kW heater costs 49p an hour at full power on the Oct 2026 price cap rate of 24.5p/kWh, and about £1.47 for a 5-hour evening once the thermostat starts cycling. Set your own heater, hours and tariff below.
Once the room is warm the thermostat switches the element on and off. In a closed, reasonably insulated room it is typically on 50–70% of the time; in a draughty room, nearer 100%.
UK Oct 2026 price cap: 24.5p/kWh
- Per day6.0 kWh
- £1.47
- Per month30 days
- £44.10
- Per winter150 days
- £220.50
Electric heater running costs by power
| Heater | Hour† | Evening* | Month* | Winter* |
|---|---|---|---|---|
| 1kW | 25p | 74p | £22 | £110 |
| 1.5kW | 37p | £1.10 | £33 | £165 |
| 2kW | 49p | £1.47 | £44 | £221 |
| 2.5kW | 61p | £1.84 | £55 | £276 |
| 3kW | 74p | £2.21 | £66 | £331 |
†At full power. *5 hours a day with the thermostat on 60% of the time; winter = 150 days. 24.5p/kWh (Oct 2026 price cap).
Heaters in stock now, by running cost
Lower power costs less per hour but heats a smaller room. As a rough guide, allow about 100W per square metre of a typical UK room.
†At full power. *5 hours at 60% of full power. In stock at the last check, lowest power first. Power is read from the retailer listing.
Electric heater running costs: common questions
- How much does a 2kW electric heater cost to run per hour?
- At the Oct 2026 price cap rate of 24.5p/kWh, a 2kW heater costs 49p an hour at full power. Once the room is warm the thermostat cycles the element, so over an evening it typically averages nearer 29p an hour.
- How much does a 3kW heater cost to run?
- 74p an hour at full power, or about £2.21 for a 5-hour evening with the thermostat cycling 60% of the time.
- Are oil filled radiators cheaper to run than fan heaters?
- Watt for watt, no: every plug-in electric heater turns 1kW of electricity into 1kW of heat. An oil radiator usually costs less over an evening because its thermostat and the oil's stored heat let it switch off for longer once the room is warm, while a fan heater without a thermostat runs flat out. Pick the lowest wattage that heats your room and use the thermostat.
- What is the cheapest electric heater to run?
- The cheapest heater to run is the lowest-powered one that still warms the space you are in. For one person, an electric blanket (about 60W) or heated throw costs pennies an hour; for a small room, a 1–1.5kW oil radiator with a thermostat; for a larger room, a 2–2.5kW radiator run on its thermostat rather than flat out.
- Is it cheaper to heat one room with an electric heater than to put the central heating on?
- Usually, if you only need one room. Electricity at 24.5p/kWh costs about four times gas per kWh, so an electric heater is dearer per unit of heat, but heating one room for a few hours uses far fewer units than heating the whole house.