Heat pump running costs: an honest winter guide
How much electricity a heat pump uses, what it costs against a gas boiler at today’s prices, and the three settings that make the biggest difference.
We get more questions about heat pumps than anything else. Here’s the arithmetic we use with customers, using the price cap that applies from 1 October 2026.
The one number that matters: SCOP
A heat pump’s seasonal coefficient of performance (SCOP) is how many kWh of heat you get for each kWh of electricity over a year. Well-designed installations in UK homes typically achieve 3.0 to 3.6. Your installer’s heat-loss survey and MCS design will give an expected figure for your home.
A worked example
Take a home that currently burns 14,000 kWh of gas a year in a 90%-efficient boiler. It needs about 12,600 kWh of heat. At a SCOP of 3.3, a heat pump uses about 3,800 kWh of electricity to deliver that.
| Energy | Cost a year | |
|---|---|---|
| Gas boiler: 14,000 kWh at 7.97p plus the gas standing charge (29.68p a day) | 14,000 kWh | £1,224 |
| Heat pump on a flat rate at the cap (26.32p) | 3,800 kWh | £1,000 |
| Heat pump on EV Nights, 35% of its use in the night window (the rest at the EV Nights day rate, 2.45p above the cap) | 3,800 kWh | £808 |
If the gas supply is capped once the heat pump is in, you also stop paying the gas standing charge, which is already included above. Electricity also carries no VAT from 1 October 2026 to 31 March 2027, which helps this winter.
Three settings that make the biggest difference
- Low and slow. A lower flow temperature (often 35–45°C) with the heating running longer is more efficient than short bursts.
- Hot water at night. Heat the cylinder once, in the night window, and run a weekly legionella cycle at the same time.
- Don’t fight the weather compensation curve. Let the system adjust to the outdoor temperature rather than turning the thermostat up and down.
Grants
The Boiler Upgrade Scheme, run by Ofgem, gives £7,500 towards an air source or ground source heat pump in England and Wales. Your MCS-certified installer applies for the voucher; you’ll get an email from Ofgem asking you to confirm. Scotland has its own Home Energy Scotland grant and loan.
Planning an installation? Tell us your install date and we’ll make sure your tariff and meter are ready for it.