Heat pump vs gas boiler: which costs less to run?
It comes down to one question: is your heat pump efficient enough to beat the price gap between electricity and gas?
Yearly cost for a typical 3-bed semi-detached house
| System | Energy used | Yearly cost |
|---|---|---|
| Gas boiler (85% efficient), incl. standing charge | 11,500 kWh gas | £1,025 |
| Heat pump, typical UK install (2.8), standard tariff | 3,491 kWh | £919 |
| Heat pump, typical UK install (2.8), Cosy Octopus | 3,491 kWh | £684 |
| Heat pump, good install (3.5), standard tariff | 2,793 kWh | £735 |
| Heat pump, good install (3.5), Cosy Octopus | 2,793 kWh | £547 |
| Heat pump, excellent install (4.2), standard tariff | 2,327 kWh | £613 |
| Heat pump, excellent install (4.2), Cosy Octopus | 2,327 kWh | £456 |
Heating and hot water only. Price cap rates for 1 October – 31 December 2026. Cosy cost assumes 60% of heating in cheap windows and 10% at peak.
What decides the answer
1. How efficient the installation is
A well-designed system with the right size radiators and a low flow temperature can reach a SCOP of 3.5 to 4 or more. A rushed install running hot can sit below 3. More on SCOP →
2. Which electricity tariff you use
A heat pump tariff lets you do most of your heating at a much lower rate. That lowers the efficiency you need to beat gas from about 2.8 to about 2.1. How Cosy Octopus works →
3. Whether you remove gas completely
No gas supply means no gas standing charge: about £108 a year back in your pocket.
FAQs
Is a heat pump cheaper to run than a gas boiler in 2026?
With a good installation, yes, especially on a heat pump tariff. With a poor installation on a standard tariff it can cost about the same or slightly more. The break-even efficiency at current prices is a SCOP of about 2.8 on a standard tariff and about 2.1 on Cosy Octopus.
Why is the price of electricity so important?
Electricity currently costs about 3.3 times as much as gas per kWh. A heat pump has to be at least that many times more efficient than a boiler to win on running costs, which is why a cheaper electricity tariff tips the balance.
Do I save the gas standing charge?
Only if you remove gas from your home completely, including any gas hob or fire. If you do, you save about £108 a year at current rates.
Is there a grant for a heat pump?
In England and Wales the Boiler Upgrade Scheme offers a grant of £7,500 towards an air source heat pump at the time of writing. Check GOV.UK for the current amount and rules. This site covers running costs only, not installation costs.
Run your heat pump on cheaper electricity
Cosy Octopus has three cheap windows a day, priced 51% below its day rate. Switch through our referral link and you also get £50 credit.
Get an Octopus Quote + £50 Credit →You need a heat pump and a smart meter. Link checked 5 October 2026.