1.5 kW heater39p
2 kW heater53p
3 kW heater79p
Your region
Live Direct Debit rates for UK average since 1 October 2026.
Cost per hour by heater type
| Heater | Typical power | Per hour | 4 hours a day for a month |
|---|---|---|---|
| Electric blanket | 130–200 W | 4.3p | £5.28 |
| Electric towel rail | 250–500 W | 9.9p | £12.01 |
| Small oil-filled radiator | 1,500 W | 39p | £48.03 |
| Oil-filled radiator | 2,000 W | 53p | £64.05 |
| Fan heater / electric fire | 2,000–3,000 W | 66p | £80.06 |
Are oil-filled radiators cheaper than fan heaters?
Not per unit of heat. Every plug-in electric heater turns electricity into heat at the same 100% efficiency, so 1 kWh of electricity gives 1 kWh of heat whatever the type. What differs is how the heat feels:
- Fan heaters warm a room quickly, which suits short bursts.
- Oil-filled radiators heat up slowly and keep giving off warmth after the thermostat switches off, which suits longer use.
The cheapest heater is the one with a good thermostat, set as low as you're comfortable with.
How the thermostat changes the cost
The figures above assume full power. Once a room reaches the set temperature, most heaters switch on and off, so a 2 kW heater might only use half its rated power over an evening in a well-insulated room.
Want to compare with your central heating? See electric heater vs central heating.
Sources: National Energy Action, Ofgem price cap via Uswitch, Octopus Energy tariff data.