How Much Does an Electric Heater Cost to Run in the UK?
Updated: October 2026
Electric heaters are simple to calculate because their electricity use is based mainly on their power rating and how long they are running.
A 2,000W heater running continuously uses 2kWh of electricity every hour.
Using the average Ofgem electricity price-cap rate of 26.32p per kWh for Direct Debit customers from 1 October to 31 December 2026, that would cost approximately 53p per hour.
Your actual cost may be different because electricity prices vary by tariff, region and payment method.
Calculate using your own electricity tariff
Enter the wattage, hours used and your actual electricity unit rate to calculate the cost of running your appliance.
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The short answer
At an electricity price of 26.32p per kWh:
• a 1,000W heater costs about 26p per hour
• a 1,500W heater costs about 39p per hour
• a 2,000W heater costs about 53p per hour
• a 2,500W heater costs about 66p per hour
These figures assume the heater draws its full rated power continuously.
Thermostatically controlled heaters may use less electricity once the room reaches the selected temperature.
Electric heater running costs
| Heater Power | Cost Per Hour | 4 Hours Per Day | 8 Hours Per Day | 30 Days at 4 Hours Per Day |
|---|---|---|---|---|
| 1,000W | £0.26 | £1.05 | £2.11 | £31.58 |
| 1,500W | £0.39 | £1.58 | £3.16 | £47.38 |
| 2,000W | £0.53 | £2.11 | £4.21 | £63.17 |
| 2,500W | £0.66 | £2.63 | £5.26 | £78.96 |
These examples use 26.32p per kWh, the average electricity unit rate under the Ofgem price cap for Direct Debit customers from 1 October to 31 December 2026.
Your electricity tariff may be higher or lower.
How to calculate the cost of an electric heater
First convert watts into kilowatts:
Kilowatts = Watts ÷ 1,000
Then multiply the heater power by the number of hours used:
Electricity used = Kilowatts × Hours
Finally multiply the electricity used by the unit price:
Running cost = kWh used × electricity price per kWh
A 2,000W heater is 2kW.
If it runs for 3 hours:
2kW × 3 hours = 6kWh
At 26.32p per kWh:
6 × £0.2632 = £1.58
So running the heater continuously for three hours would cost approximately £1.58.
How much does a 2kW heater cost to run?
A 2kW heater uses up to 2kWh of electricity for every hour that the heating element is continuously active.
At 26.32p per kWh:
1 hour:
approximately £0.53
4 hours:
approximately £2.11
8 hours:
approximately £4.21
4 hours per day for 30 days:
approximately £63.17
This represents continuous full-power operation. A thermostat may switch the heating element on and off after the room reaches temperature.
How much does a 2.5kW heater cost to run?
A 2.5kW heater running continuously uses 2.5kWh per hour.
At 26.32p per kWh this costs approximately:
1 hour:
£0.66
4 hours:
£2.63
8 hours:
£5.26
4 hours per day for 30 days:
£78.96
Is an oil-filled radiator cheaper than a fan heater?
Not simply because it is oil-filled.
Electric resistance heaters convert electricity into heat very efficiently at the point of use.
If a 2kW oil-filled radiator and a 2kW fan heater both draw their full 2kW continuously for one hour, they use roughly the same amount of electricity and therefore cost roughly the same to run.
The difference is how they deliver and control the heat.
Oil-filled radiators store some heat in the oil and metal body and can continue releasing warmth after the heating element switches off.
Fan heaters warm the air quickly but normally have less stored heat once switched off.
In real use, thermostats, room size, insulation and how frequently the heating element cycles can therefore change total electricity consumption.
Does a thermostat reduce heater running costs?
Yes, potentially.
The wattage printed on a heater is normally its maximum electrical power while the heating element is operating.
A thermostatically controlled heater may switch the heating element off once the selected temperature is reached and turn it back on when the room cools.
For example, a 2kW heater does not necessarily consume 2kWh during every clock hour if its thermostat only requires the heating element to operate for part of that hour.
Why insulation matters
The heater replaces heat that the room loses.
A poorly insulated room can lose heat more quickly through windows, walls, floors, ceilings and draughts, causing the heater to operate for longer.
Reducing heat loss can therefore reduce the amount of electricity needed to maintain the same indoor temperature.
Practical measures can include:
• closing doors between heated and unheated rooms
• reducing draughts
• closing curtains at night
• improving loft or wall insulation where appropriate
• avoiding heating unused rooms unnecessarily
What if I have a cheap overnight electricity tariff?
If your electricity tariff has different peak and off-peak prices, the cost depends on when the heater operates.
For example, a 2kW heater operating for one hour uses approximately 2kWh.
At 30p per kWh that costs:
60p
At 10p per kWh that costs:
20p
This can make the timing of electric heating important for households with multi-rate or time-of-use tariffs.
Should the electricity standing charge be included?
For most appliance comparisons, the standing charge is not added to the heater’s running cost because the household normally pays it whether the heater is switched on or not.
For 1 October to 31 December 2026, Ofgem’s average electricity standing charge for Direct Debit customers is 54.83p per day.
If you are estimating your total household electricity bill rather than the incremental cost of one appliance, the standing charge should also be considered.
Electric Heater Running Cost FAQs
How much does a 2kW heater cost per hour?
At 26.32p per kWh, a 2kW heater operating continuously costs approximately 53p per hour.
How much does a 2.5kW heater cost per hour?
At 26.32p per kWh, approximately 66p per hour when operating continuously at full power.
Does a 2kW heater always use 2kWh every hour?
Only if the heating element operates continuously for the entire hour. A thermostat may cycle the element on and off, reducing actual electricity use.
Are oil-filled radiators cheaper to run?
A heater with the same electrical power rating uses approximately the same electricity while its heating element is operating. Differences in thermostatic control, heat storage and usage patterns can affect real-world consumption.
Is electric heating cheaper at night?
It can be if you have a tariff with a lower overnight or off-peak electricity rate. A standard single-rate tariff normally charges the same unit price throughout the day.
Does the standing charge increase when I use a heater?
No. The standing charge is normally a fixed daily charge and does not increase because one particular appliance is switched on.
Sources and methodology
The worked examples in this guide use an electricity price of 26.32p per kWh.
This is the average Ofgem electricity price-cap unit rate for Direct Debit customers in England, Scotland and Wales from 1 October to 31 December 2026.
The average standing charge for the same period is 54.83p per day.
Actual electricity prices vary by region, tariff and payment method.
Rates last checked: 6 October 2026.