How Much Does an Electric Heater Cost to Run? 2kW Costs Per Hour, Evening and Month

Quick answer: A 2kW electric fan heater on full power costs about 52p per hour at the July–September 2026 price cap of 26.11p/kWh. A four-hour evening costs around £2.09, and running it every evening for a month adds roughly £63 to your electricity bill.

All costs on this page are calculated at the July–September 2026 Ofgem price cap for Direct Debit customers: 26.11p per kWh of electricity, with gas comparisons at 7.33p per kWh. Unit rates vary slightly across the 14 GB regions, so treat these as good averages and check the rate on your own bill.

The sum: how to work out any electric heater’s running cost

Electric heater maths is refreshingly simple. Power in kilowatts × hours used = energy in kilowatt-hours (kWh), and every kWh of electricity costs 26.11p at the current cap. So a 2kW fan heater running flat out for one hour uses 2kWh: 2 × 26.11p = 52.22p — call it 52p. That one calculation covers every plug-in heater in your home; only the kilowatt rating changes.

Fan heaters are resistance heaters, which means they convert essentially all of the electricity they draw into heat. There is no efficiency difference worth shopping around for — a 2kW fan heater from any brand produces the same amount of warmth for the same money. What varies is how quickly and how evenly that warmth reaches you.

2kW fan heater running costs: hour, evening, week and month

These figures assume the heater runs continuously at full power, which is the worst case. Most fan heaters have a lower 1kW setting — which halves every number above to 26p per hour — and a thermostat that switches the element off once the room reaches temperature. In a small, reasonably well-insulated room, a thermostat-controlled heater will often cost noticeably less than the table suggests because it spends part of each hour switched off.

How that compares with gas central heating

Gas costs 7.33p per kWh at the current cap. Allowing for a modern boiler running at around 85–90% efficiency, a kWh of useful heat from gas works out at roughly 8.5–9p — about a third of the 26.11p you pay for the same heat from a plug-in electric heater. That is why a fan heater makes sense for a short burst of warmth in one room, but becomes an expensive way to heat a whole home for hours on end.

For context, an air source heat pump typically delivers around three units of heat for every unit of electricity it uses, bringing its effective cost per kWh of heat down to roughly 9p too. Our heat pump guide explains how that works.

When a plug-in fan heater is the right choice

Fan heaters earn their keep when you need fast, short-lived heat in a single space: half an hour in a home office before the central heating kicks in, taking the chill off a bathroom, or warming a spare room that the radiators don’t reach. Used that way — 30 to 60 minutes at a time — you are looking at 26–52p a session, not the £60-plus monthly figures that come from treating one as your main heating.

Five ways to cut the cost

• Use the 1kW setting where you can — it halves the hourly cost to around 26p and is often enough once a small room is warm.
• Heat the person, not the room: an electric blanket costs pennies a night compared with £2-plus for an evening of fan heating.
• Set the thermostat a notch or two lower and let it cycle — every degree you don’t need is money saved.
• Draught-proof the room and top up insulation so the heat you pay for stays put.
• Match the heater type to the job — our portable heater comparison shows when radiant or oil-filled models work out better.

FAQs

Is it cheaper to run a fan heater or the gas central heating for one room?

If you genuinely only need one small room warm for an hour or two, a 2kW fan heater at around 52p an hour can beat firing up the whole boiler and heating every radiator in the house. For longer periods, or more than one room, gas wins at roughly a third of the price per unit of heat — turning down radiator valves in unused rooms is usually the better fix.

How much does it cost to run a 2kW heater overnight?

Eight hours at full power is 16kWh — about £4.18 at the current cap. On the 1kW setting with the thermostat cycling, it might be nearer £1–£2, but for sleeping comfort an electric blanket at roughly 8p a night is far cheaper and safer than leaving a fan heater running.

Why does my smart meter show more than 52p for an hour of heating?

Three usual reasons: the 57.19p daily standing charge is always ticking away on top of usage, other appliances are running at the same time, and your regional unit rate may be a little above the 26.11p GB average. Our guides to the price cap and reading your energy bill break both down.