UK running cost calculator

Electric Heater Cost Calculator UK

Estimate how much your electric heater could cost to run per day, week, month, and year using your heater power, usage, and an editable UK electricity rate.

Last reviewed: 25 April 2026

Calculator inputs

Enter your electric heater details, adjust the tariff if needed, and calculate a quick UK-style running-cost estimate.

Electric heater power

Choose watts or kW. Maximum 20000 watts.

Power unit

Watts (W)Kilowatts (kW)

Switch units without changing the underlying power value.

Hours used per day

hours

Use up to 24 hours. Decimals are fine for part-day use.

Electricity rate

Start with the Ofgem default, then change payment type or region to load the matching unit rate automatically.

Rate source

Keep the Ofgem option on to auto-fill the unit rate from the selected payment type and region.Payment type

Changing payment type updates the Ofgem unit rate automatically when the Ofgem source is selected.

Region

Choose your region to load the matching Ofgem single-rate electricity unit rate automatically.Unit rate

p/kWh

The rate auto-fills from Ofgem when that source is selected, but you can still edit it manually at any time.

Default rate based on Ofgem average electricity unit rate for 1 April to 30 June 2026. Your actual tariff may vary.

Standing charge is not included.

Source: Ofgem energy price cap unit rates.

Days used per week

days

Choose between 0 and 7 days each week.

Result Card

Estimated running cost

Based on 8 kWh per day at 24.67 p/kWh. Standing charge is not included because this estimates one appliance only.

Cost per day£1.97

2 kW x 4 hours = 8 kWh

Cost per week£13.82

7 days used per week

Cost per month£60.03

Weekly cost x 4.345

Cost per year£718.39

Weekly cost x 52

How this is calculated

See the exact steps behind the estimate so the result stays easy to sense-check.

kWh per day = kW x hours per day
daily cost = kWh per day x price per kWh
weekly cost = daily cost x days per week
monthly cost = weekly cost x 4.345
yearly cost = weekly cost x 52

This calculator does not include any standing charge because it is only estimating the running cost of the appliance itself.

Example calculation

A worked example helps the user compare the result with a familiar everyday scenario.

A 2 kW heater used for 4 hours a day uses 8 kWh each day.

At 24.67 p/kWh, that works out to about 1.97 GBP per day, 13.82 GBP per week, 60.02 GBP per month, and 718.39 GBP per year when used every day.

Tips to reduce cost

Small household changes can often reduce running costs without overcomplicating the decision.

Use a timer so the heater runs only when you need it most.
Check the room size before relying on a small heater for long periods.
Close doors and reduce drafts to keep heat in for longer.
Compare heater cost with better-insulated options or a different heating setup.

Calculator

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Estimate notice

This is an estimate. Your actual cost may vary depending on your tariff, region and appliance usage.