DATA-BACKED GUIDE · UPDATED JULY 2026
Air source heat pump running costs in the UK: what to expect per year
Plenty of homeowners worry less about the fitting bill and more about what a heat pump costs to run once it is switched on. The annual figure hinges on your electricity tariff, how well the house holds heat, and the flow temperature your installer dials in. The real prices below come from people who have shared their bills, so you can weigh a pump against a gas boiler with actual numbers rather than guesswork.
The quick version
- Heat pumps run on electricity, so your unit rate and any dedicated heat pump tariff swing the yearly cost more than anything else.
- A warm, well insulated home running at a low flow temperature is far cheaper to heat than a draughty one.
- The £7,500 Boiler Upgrade Scheme grant lowers the upfront cost of an air source heat pump, which brings the payback period forward.
- Fitting a heat pump counts as an energy-saving measure, so it carries 0% VAT until 2027.
What people actually paid
Real prices, in people's own words
- £2,200“Mine was £2.2k after BUS from Octopus, 8 rads.”
- £2,900“I paid £1300 (ASHP), £1000 for cylinder and another £600ish for stuff.”
- £3,000“I paid roughly £10500 for a 7kW aurotherm plus with 300l UVC, no buffer tank as one zone and full install. Minus the Home Energy Scotland Grant (£7500) I paid £3000”
- £6,500“My Octopus install cost around £11,500 and I paid £6,500 after the grant”
- £8,500“I got a full package from coolenergy, heatpump, buffer, 300l HWC, carel controller, glycol, the works. That was £6300 after vat reclaim.”
- £12,000“We where charged 12k minus the grant for an 11 KW Mitsubishi”
Genuine amounts posted publicly. We publish the price and the quote, never the person.
Why the price varies so much
The running cost gap between two identical houses can be huge, and it usually comes down to the details. A pump running at 35 degrees through big radiators or underfloor pipes sips electricity, while the same unit forced up to 55 degrees to feed small old radiators drinks it. Your seasonal efficiency, often quoted as an SCOP, decides how many units of heat you get for each unit of power, and that shifts with the weather and how the system was commissioned. On top of that, a standard variable tariff will cost you far more than a smart tariff with a cheap overnight window. Insulation, hot water habits and where you set the thermostat all feed in too, which is why one household raves about their bills while a neighbour grumbles.
How to pay less
- Switch to a time-of-use or dedicated heat pump electricity tariff so you buy your units when they are cheapest.
- Insulate before you install. Loft and cavity wall work cuts the heat demand the pump has to meet all winter.
- Ask the installer to commission the system at the lowest flow temperature your radiators can cope with.
- Get three quotes and check each one has done a proper room-by-room heat loss survey rather than eyeballing it.
Common questions
Is an air source heat pump cheaper to run than a gas boiler?
It can be, but it is not automatic. A well set up pump in an insulated home on a smart tariff often undercuts gas, while a poorly commissioned one on a standard tariff can cost more. The real prices below show the spread, and the deciding factors are your tariff, insulation and flow temperature.
Do heat pumps still work in the middle of winter?
Yes. Air source heat pumps pull heat from the outside air even below freezing, they just work a little harder on the coldest days, which nudges the running cost up briefly. A correctly sized unit will keep the house warm through a normal British winter.
Does the £7,500 grant help with running costs?
No. The Boiler Upgrade Scheme grant only reduces the upfront installation cost of an air source heat pump. Lower running costs come from your tariff, your insulation and a system commissioned to run efficiently.