How much does a 2 kW electric heater cost per month in the UK?
At 26.11p per kWh, a 2 kW heater used for five hours a day costs £78.33 over 30 days at continuous full power. At 50% thermostat activity, the estimate is £39.17.
How much does electric heating cost per month in the UK?
At 26.11p/kWh, a 2 kW heater used five hours daily costs £78.33 over 30 days at full power—or about £39.17 at 50% thermostat activity.
Heater size
Five active hours per day.
This table compares four common electrical inputs over 30 days. It assumes the heater draws full power for all five hours.
Heater inputDaily energyMonthly energy30-day cost
500 W2.5 kWh75 kWh£19.58
1 kW5.0 kWh150 kWh£39.17
1.5 kW7.5 kWh225 kWh£58.75
2 kW10.0 kWh300 kWh£78.33
Thermostat scenarios
A 2 kW heater scheduled for five hours.
“Active share” is the portion of the five-hour window during which the heating element actually draws 2 kW.
Active shareActive time/dayMonthly energy30-day cost
25%1.25 hours75 kWh£19.58
50%2.50 hours150 kWh£39.17
75%3.75 hours225 kWh£58.75
100%5.00 hours300 kWh£78.33
Rate and evidence
Based on a current official reference.
The examples use Ofgem default tariff cap for Great Britain: GBP 0.2611/kWh, effective 2026-07-01 to 2026-09-30.
The Ofgem cap is an average reference for eligible default tariffs in Great Britain. Your region, payment method, meter and contract may produce a different unit rate.
Confidence A 99/10026.11p per kWh
The standing charge is excluded because running the heater does not add another daily standing charge.
Source: Ofgem price-cap unit rates and standing charges ↗One room or a whole-home heating bill?
This page models a resistive electric heater. To estimate several rooms, calculate each heater separately and add the kWh. For example, two 2 kW heaters scheduled five hours daily at 50% activity use 300 kWh over 30 days. At an illustrative £0.25/kWh, that is £75 for the heaters, excluding standing charges and other appliances.
Running cost is different from installation cost
The result covers electricity used, not buying the heater, installation, wiring or maintenance. Storage heaters need a model of their charging schedule and tariff periods; heat pumps need an efficiency model. Do not apply this heater example as a prediction for every electric heating system.
Compare hourly UK heater cost or find your electricity unit rate.
Calculation
Make active time explicit.
Monthly cost = kW × scheduled hours × active share × days × unit rateDo not add the household standing charge to the heater. It is payable regardless of whether this one appliance runs.
Interpretation
Wattage alone does not predict the month.
01
Insulation and draughtsLower heat loss can reduce the time the thermostat keeps the element active.
02
Heating one roomA portable heater is not directly comparable with whole-home heating unless comfort and heated area are matched.
03
Heat pumpsThey move heat rather than producing it only through resistance, so use a separate efficiency model.
Common UK questions
Electric-heater cost, answered.
These answers separate full-power use from thermostat-controlled use so the monthly estimate stays realistic.
Does a 2 kW heater use 2 kWh every hour?
It uses 2 kWh during one complete hour at full power. After a room warms, a thermostat may switch the element off for part of the scheduled hour, reducing average energy use.
Is an oil-filled radiator cheaper to run than a fan heater?
At the same electrical input, resistive heaters cost broadly the same while their elements are active. Room heat loss, thermostat control, comfort and total runtime determine the monthly difference.
Should the electricity standing charge be included?
No. The household standing charge is payable whether this heater runs or not, so it should not be assigned to one appliance's running cost.