How much does an electric heater cost to run?
Enter the heater's input power, how long you use it and your own tariff. The calculator shows energy use and estimated running cost immediately.
How this calculator works
Electric heaters convert nearly all their input power directly into heat, which makes them one of the more predictable appliances to cost — but also one of the most expensive to run for long hours. EuroWattCalc converts the heater's wattage to kilowatts, multiplies by the hours and days it runs, and applies your electricity price to the total.
What can change the real cost?
- A thermostat can switch the heating element on and off, so a 2,000 W heater may not draw 2,000 W continuously for every hour.
- Room insulation, outdoor temperature, thermostat setting and room size affect how long the heater needs to run.
- Fixed charges on an electricity bill are not caused by one appliance and are therefore excluded from this usage-cost estimate.
Use this as a planning estimate rather than a promise about a future bill. The most accurate input comes from measured power and the unit rate on your own tariff.
Frequently asked questions
Does a 2 kW heater use 2 kWh every hour?
If it draws a continuous 2 kW for a full hour, yes. A thermostat may reduce actual energy use by cycling the heating element.
Is a lower wattage heater always cheaper?
It costs less per hour while drawing less power, but it may need to run longer to deliver the same amount of heat.
Should I include my standing charge?
No for appliance comparison. Use the unit price per kWh; standing charges are fixed bill components rather than usage from the heater.
Typical electric heater running costs
Electric heaters are one of the biggest seasonal swings in a European household's power bill. Because resistive heating elements convert nearly all incoming electricity into heat, wattage maps almost directly onto cost — there is no efficiency multiplier to soften a high rating the way there is with a heat pump. That makes heaters a useful case study for understanding home energy costs generally: the number on the appliance label, multiplied by how long it actually runs, is most of the story.
| Scenario | Power | Use | Approx. cost* |
|---|---|---|---|
| Small fan heater | 750–1,000 W | 2 h/day | €0.09–€0.12 |
| Standard convector heater | 2,000 W | 4 h/day | €0.48 |
| Oil-filled radiator | 2,000 W | 8 h/day (overnight) | €0.96 |
| Large panel heater | 3,000 W | 3 h/day | €0.54 |
*Estimated at €0.30/kWh usage price. Your own tariff, appliance model and habits will change the real figure — use the calculator above with your own numbers.
More frequently asked questions
Is an oil-filled radiator cheaper to run than a fan heater?
Both convert electricity to heat at essentially 100% efficiency, so a 2,000 W oil-filled radiator and a 2,000 W fan heater cost the same per hour at the same wattage. The radiator often feels cheaper because it holds heat and cycles off more, not because the watts themselves are more efficient.
Does a thermostat reduce the cost shown here?
Yes. A thermostat cycles the heater on and off, so actual daily running hours are usually lower than the heater's rated power would suggest if left on continuously. Use your best estimate of actual on-time, not the full day, for a realistic figure.
