- Ofgem cap averages, 1 October to 31 December 2026: electricity 26.32p per kWh, gas 7.97p per kWh.6
- An electric heater turns each kWh it uses into heat, so its heat costs 26.32p per kWh. A gas boiler loses some heat: for a system fitted now, Approved Document L sets a minimum efficiency of 92%.1
- If your boiler meets that minimum, gas heat costs 8.66p per kWh (7.97p / 0.92), about a third of the electric price. Older boilers may be less efficient.
- Last checked: 28 October 2026.
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The same heat, two ways
2 kWh of heat, the output of a 2 kW heater for an hour: 52.6p from the heater, 17.3p from gas at 92% efficiency.
| Heat delivered | Electric heater | Gas at 92% |
|---|---|---|
| 1 kWh | 26.3p | 8.7p |
| 2 kWh | 52.6p | 17.3p |
| 5 kWh | £1.32 | 43.3p |
| 10 kWh | £2.63 | 86.6p |
The 92% is “Wet heating (e.g. radiators or underfloor heating) 92%”, the minimum for gas wet heating fitted now in England. It is not a measure of how efficient any particular boiler is in use.1
Heating one room instead of the whole house
A plug-in heater can cost less overall if it means the central heating stays off and you only need one room warm. It depends on how much heat each option has to deliver, which we cannot measure for your home.
The NHS: “If you can, this should be at least 18°C in the rooms that you regularly use, such as your living room and bedroom.” This is particularly important if you have a health condition.2
Government damp and mould guidance for England says homes “insufficiently insulated and heated are more prone to the build-up of moisture”.3
Safety
The Home Office: “Always unplug electric heaters when you go out or go to bed.” and “Keep heaters away from curtains and furniture and never use them for drying clothes.”4
Gas standing charges
Gas standing charges: the Budget asks Ofgem to abolish them, “aiming for delivery by the end of 2027” or as soon as possible after (announced, needs legislation). “Ofgem will ensure that energy suppliers recover these costs through gas unit rates instead”, so the cost moves into the price per kWh: you will not save the whole standing charge.5
Who these figures cover
Costs use the Ofgem price cap average for England, Scotland and Wales, 26.32p per kWh by Direct Debit, 1 October to 31 December 2026. Your region and tariff change it.6
HMRC: “The temporary zero rate applies from 1 October 2026 to 30 June 2027.” The Budget on 28 October 2026 extended it from 31 March (announced; the legislation is due in early 2027). Gas stays at 5% VAT.7 In Northern Ireland, use the unit rate on your bill.