What is the cheapest electric heater to run?
Every electric heater turns electricity into heat at the same rate, so the cheapest one to run is the right size, with a thermostat and timer. Here is what each type costs per hour at the price cap.
Running cost by type, cheapest first
| Appliance | Per hour | 4 hours a day, a month | Best for |
|---|---|---|---|
| Heated throw (150 W) | 3.9p | £4.74 | Warms you, not the room |
| Electric blanket (about 60 W) | 1.6p | £1.90 | Warms the bed |
| Small oil filled radiator (650 W) | 17.1p | £20.53 | Keeps a small room warm for hours |
| Ceramic heater (1.5 kW) | 39.5p | £47.38 | Quick heat for a bedroom or office |
| Oil filled radiator (2 kW) | 52.6p | £63.17 | Steady heat for a living room |
| Fan heater (3 kW) | 79.0p | £94.75 | Garages and big rooms |
At full power, at the Ofgem price cap (26.32p/kWh). Electric blanket figure is typical; check the label on yours.
The truth about energy efficient heaters
Every plug-in electric heater is 100 % efficient: 1 kWh of electricity becomes 1 kWh of heat, whatever the brand or the advert says. So no heater is cheaper per unit of heat than another. What changes the bill is:
- Power: the smallest heater that keeps you warm.
- Controls: a thermostat that stops it once the room is warm, and a timer so it is not left on.
- Where the heat goes: warming yourself (heated throw) or one room with the door shut costs far less than heating the whole house.
Only a heat pump (including air conditioning units that can heat) gives more heat than the electricity it uses, typically about 3 times as much.
Cost for every heater size
| Power | 1 hour | 3 hours a day, a month | On a thermostat* |
|---|---|---|---|
| 500 W | 13.2p | £11.84 | £7.11 |
| 1 kW | 26.3p | £23.69 | £14.21 |
| 1.5 kW | 39.5p | £35.53 | £21.32 |
| 2 kW | 52.6p | £47.38 | £28.43 |
| 2.5 kW | 65.8p | £59.22 | £35.53 |
| 3 kW | 79.0p | £71.06 | £42.64 |
At the Ofgem price cap (26.32p/kWh, Direct Debit, 1 October to 31 December 2026). * A heater on a thermostat is assumed to heat about 60 % of the time once the room is warm.
Our picks for cheap warmth
Russell Hobbs RHOFR3001W 650W 5 Fin Oil Filled Radiator
- Oil filled radiator · 650 W
- Small 650 W oil radiator with adjustable thermostat for rooms up to 10 m²: one of the cheapest ways to keep a small room or office warm for hours.
- Costs 17.1p an hour at full power.
Silentnight Comfort Control Heated Throw 120x160cm
- Heated throw · 90 W
- Fleece heated throw with 9 heat settings, fast heat-up and safety shut-off: keeps you warm on the sofa for a few pence an hour.
- Costs 2.4p an hour at full power.
Dreo Atom 316 Ceramic Heater 1500W
- Fan heater · 1,500 W
- One of the most-reviewed ceramic heaters on Amazon UK: quiet (34 dB), digital thermostat, 12-hour timer and remote. Warms a bedroom or home office in minutes.
- Costs 39.5p an hour at full power.
If you buy through our links, Amazon pays us a small commission. The price is the same for you.
🧮Gas, electric or heat pump? Compare the cost of each with your own prices→Frequently asked questions
What is the cheapest electric heater to run?
The one with the lowest power that keeps you warm, with a thermostat and timer. A 650 W oil filled radiator costs 17.1p an hour, a heated throw about 3.9p.
Do energy saving heaters really save energy?
Not per unit of heat: all plug-in electric heaters are 100 % efficient. They save money only through better controls (thermostat, timers, eco modes) or lower power.
Is it cheaper to heat one room with an electric heater than to use gas central heating?
For one room for a few hours, often yes, because you don't heat the whole house. Per unit of heat, mains gas (7.97p/kWh) is much cheaper than electricity (26.32p/kWh). See the full comparison in our cheapest way to heat guide.
Are oil filled radiators cheaper to run than fan heaters?
Per hour at the same power, no. Over an evening they often cost less, because they hold heat and the thermostat keeps them off for longer.
Running costs use the Ofgem energy price cap, 1 October to 31 December 2026: average unit rate for electricity paid by Direct Debit (26.32p/kWh, standing charge 54.83p/day) and gas (7.97p/kWh). National averages; your region and tariff may differ. Prices on Amazon change: check the live price before you buy.