Work out what an electric heater costs per hour, per day, per week or per month in a UK home using current electricity assumptions and your own use pattern.
A 2kW electric heater costs about £0.49 per hour at full power using 24.67p/kWh electricity. Four hours costs about £1.97; four hours every day for 30 days costs about £59.21 at full power, or about £38.49 at 65% average output.
Use this as the fast full-power benchmark before adjusting for thermostat cycling, room size or your own tariff.
| Heater size | Cost per hour | 4 hours | 7 days at 4h/day | 30 days at 4h/day | 30 days at 65% average output |
|---|---|---|---|---|---|
| 500W | £0.12 | £0.49 | £3.45 | £14.80 | £9.62 |
| 1kW | £0.25 | £0.99 | £6.91 | £29.60 | £19.24 |
| 1.5kW | £0.37 | £1.48 | £10.36 | £44.41 | £28.86 |
| 2kW | £0.49 | £1.97 | £13.82 | £59.21 | £38.49 |
| 2.5kW | £0.62 | £2.47 | £17.27 | £74.01 | £48.11 |
Current rate used: 24.67p/kWh electricity, 5.74p/kWh gas, based on Ofgem price cap, 1 April to 30 June 2026 for Direct Debit customers. Your actual tariff can differ by supplier, region, payment method and meter type.
Use this when the table is too blunt. The duty-cycle input lets you model a thermostat-controlled heater that does not stay at full power all evening.
100% means the heater stays at full power. 65% means it averages roughly two thirds of full output across the time entered.
These are intentionally direct because most heater-cost questions need the number first and the caveats second.
About £0.49 per hour at full power with 24.67p/kWh electricity.
About £1.97 at full power, before any thermostat cycling is allowed for.
A 2kW heater used four hours daily costs about £59.21 over 30 days at full power.
It can be for regular room or whole-home heat because electricity costs 24.67p/kWh versus 5.74p/kWh gas on the current benchmark.
At the same wattage and runtime, direct electric heaters cost the same per kWh. The practical difference is how they feel and how long they stay near full output.
| Heater type | Typical cost angle | Best fit | Useful next page |
|---|---|---|---|
| Fan heater | Fast heat, often 2kW, about £0.49/hour at full power. | Short bursts and quick warm-up. | Fan heater running cost |
| Oil-filled radiator | Same kWh logic, but steadier heat and thermostat cycling can change real use. | Longer room sessions where comfort matters. | Oil-filled radiator running cost |
| Panel heater | Simple direct electric heat; controls and schedule matter. | Regular room heating with sensible timers. | Panel heater running cost |
| Infrared heater | Often lower wattage, but only cheaper if targeted heat solves the job. | Spot comfort rather than whole-room heating. | Infrared heater running cost |
(watts / 1000) x hours used x electricity price per kWh x average output factor
For example, a 2kW heater for four hours at full power uses 8kWh. At 24.67p/kWh, that is £1.97.
Short answers to the questions this page is built to solve.
At 24.67p per kWh, a 2kW heater costs about 49p per hour at full power. If it cycles down after the room warms up, the average cost can be lower.
A 2kW heater used four hours a day at full power costs about GBP 59.21 over a 30-day month at 24.67p per kWh. Regular whole-room electric heating can therefore become expensive quickly.
At the same wattage and runtime, direct electric heaters cost the same per kWh. The practical difference is warm-up speed, comfort, controls and how long the heater stays near full output.