Heat Pump Cost Calculator
Find the size of heat pump your home needs, compare budget, mid-range and premium options, and see the likely price after the government grant. Takes about three minutes.
Deducts the £7,500 Boiler Upgrade Scheme grant (£9,000 if you're on oil or LPG) and compares running costs at the price cap for 1 October – 31 December 2026.
Our calculator is being updated
We are refining the figures behind this calculator so the estimates it gives are as accurate as we can make them. It will be back shortly.
In the meantime we will put a proper figure together for your home, free and with no obligation — it will be more accurate than any calculator anyway.
How the Calculator Works
The same steps a surveyor goes through, in rough form.
It Sizes the Heat Pump to Your Home
Your home's age, type, size and insulation give an estimate of the heat it loses on the coldest day. If you tell us how much gas, oil or LPG you use, we blend that in — it reflects how the house really behaves.
Budget, Mid-Range or Premium
Each option is priced fully installed: the outdoor unit, a hot water cylinder, controls, pipework, electrics, removal of your old boiler, commissioning and the grant paperwork. Add larger radiators, a powerflush or smart room controls if you want them.
Honest Running Costs
Against a modern gas boiler, a heat pump on a standard tariff costs about the same to run, or a little less. Against oil, LPG or storage heaters it is usually cheaper. The calculator shows your numbers rather than a headline.
Calculator Assumptions
Every figure it uses. A room-by-room survey replaces all of them.
| Variable | Value Used | Note |
|---|---|---|
| Boiler Upgrade Scheme grant | £7,500 (£9,000 oil/LPG) | England and Wales. Higher amount 21 July 2026 – 31 March 2027 |
| Electricity | 26.32p/kWh | Ofgem cap, 1 Oct – 31 Dec 2026 |
| Gas | 7.97p/kWh | Ofgem cap, 1 Oct – 31 Dec 2026 |
| Oil / LPG | 6.5p / 9p per kWh | Typical 2026 prices — these aren't capped and move a lot |
| Heat pump efficiency | 2.9 – 3.3 for heating, 2.5 for hot water | Deliberately conservative. Higher with right-sized radiators or underfloor heating |
| Design conditions | 21°C inside, −2°C outside | The standard MCS design day for this part of England |
| VAT | 0% | Heat pumps are zero-rated for homes until 31 March 2027 |
What It Cannot Tell You
Worth knowing before you treat the number as gospel.
Every Radiator
A heat pump runs cooler than a boiler, so some rooms need a bigger radiator. The calculator estimates how many; the survey checks each room.
Where the Unit Goes
The outdoor unit needs a flat spot on an outside wall, with space around it and a sensible distance from neighbours. Most homes have one; we confirm it on site.
Your Pipework
Thin microbore pipes can limit how much heat reaches a room. If you have them, some sections may need replacing — that is priced on survey.
Want the Real Number?
The calculator gets you close. A free survey gets you a fixed price in writing, based on a room-by-room heat-loss calculation. Heat pumps are installed and certified by our MCS-certified heat pump partner, who claims the grant for you. We are based in Milton Keynes and cover Buckinghamshire, Bedfordshire and Northamptonshire.
No obligation • Fixed pricing • Grant handled for you • Based in Milton Keynes