Heat pump for a 3 bed house: cost and running costs
The short answer
- £10,500 to £15,500 installed for a 3 bed house, or £3,000 to £8,000 after the £7,500 grant
- 8 kW to 9.5 kW is the usual size, smallest for a mid-terrace and largest for a detached house or bungalow
- £593 to £708 a year to run on a heat pump tariff, against £781 to £932 for gas
Updated 15 October 2026. Every figure on this page comes from our published model; see where our data comes from.
A heat pump for a 3 bed house is usually between 8 kW and 9.5 kW, depending on how the house is built. The tables on this page use a 3 bed semi, the typical case, and the last table compares the other kinds of 3 bed house. With average insulation a semi needs about 9 kW. Installers recorded a typical cost of £11,000 to £15,500 for a heat pump of that size under the Boiler Upgrade Scheme, with a median of £12,700. After the £7,500 grant, most pay £3,500 to £8,000.
What it costs
Size, and so price, follows how much heat the home loses. These are the typical size and the recorded installed cost for a 3 bed house at each level of insulation. The installed cost is the whole job as installers reported it to the scheme: the heat pump, hot water cylinder, labour and VAT, before the grant. Some homes also need larger radiators, which can add to it; see radiator sizing.
| Insulation | Typical size | Median installed | Middle half of installs | Median after £7,500 grant |
|---|---|---|---|---|
| Poorly insulated | 10 kW | £13,300 | £11,500 to £16,000 | £5,800 |
| Average | 9 kW | £12,700 | £11,000 to £15,500 | £5,200 |
| Well insulated | 7.5 kW | £12,300 | £10,500 to £15,000 | £4,800 |
| Recently retrofitted | 5.5 kW | £11,700 | £10,000 to £14,000 | £4,200 |
Middle half of installs: the scheme's lower and upper quartile, scaled to each median. Homes replacing oil or LPG get £9,000 instead of £7,500 until March 2027.
What it costs to run
Running costs use the median efficiency measured across 428 heat pumps in the government's Electrification of Heat trial, at the Ofgem price cap for October to December 2026. The tariff matters more than almost anything else: see heat pump tariffs.
| Insulation | Gas boiler | Heat pump, standard rate | Heat pump tariff, 18.7p |
|---|---|---|---|
| Poorly insulated | £973 | £1,134 | £806 |
| Average | £877 | £937 | £666 |
| Well insulated | £745 | £726 | £516 |
| Recently retrofitted | £544 | £497 | £353 |
Which 3 bed house costs least to heat?
A 3 bed house is not one price, because the shape of the building changes how much heat it loses. Across the five kinds below the middle half of installs runs from £10,500 to £15,500, which is £3,000 to £8,000 after the £7,500 grant. In the government meter data a mid-terrace uses the least, about 8,820 kWh of heat a year, so it needs about 8 kW. A semi uses about 9,900 kWh and needs about 9 kW. A bungalow and a detached house, with more outside wall and roof, use about 10,350 and 10,530 kWh and need about 9.5 kW. On a 18.7p heat pump tariff the running cost follows: £593 a year for the mid-terrace, £666 for the semi and £708 for the detached house, against £781, £877 and £932 for gas.
Insulation moves the figure more than the shape does. The same semi needs about 10 kW when poorly insulated and about 7.5 kW once it is well insulated, which is why a retrofit plan puts insulation first. For one kind of house in detail see the guides for a 3 bed semi, 3 bed detached, 3 bed mid-terrace, end terrace and bungalow.
Compared with similar homes
| Home, average insulation | Typical size | Installed, middle half | Heat pump tariff running cost |
|---|---|---|---|
| 3 bed semi | 9 kW | £11,000 to £15,500 | £666 |
| 3 bed detached | 9.5 kW | £11,000 to £15,500 | £708 |
| 3 bed mid-terrace | 8 kW | £10,500 to £15,000 | £593 |
| 3 bed end-terrace | 8.5 kW | £11,000 to £15,500 | £624 |
| 3 bed bungalow | 9.5 kW | £11,000 to £15,500 | £696 |
For your own figures, use the heat pump calculator, or build a retrofit plan that puts insulation first and sizes the heat pump for the home after it.
Frequently asked questions
How much does a heat pump cost for a 3 bed house?
Typically £11,000 to £15,500 installed for a 9 kW heat pump, with a median of £12,700, from what installers recorded under the Boiler Upgrade Scheme in 2025/26. After the £7,500 grant that is £3,500 to £8,000, or £2,000 to £6,500 if you are replacing oil or LPG.
Is a heat pump cheaper to run than gas in a 3 bed house?
On a 18.7p heat pump tariff, yes: about £666 a year against £877 for gas with average insulation. On a standard electricity tariff it costs about £937, a little more than gas. Both figures are energy only; gas also carries a £108 a year standing charge you save if you cap the supply.
What size heat pump does a 3 bed house need?
About 9 kW with average insulation, and less once it is well insulated. The exact size comes from the room by room heat loss calculation an MCS installer must do. See our guide to heat pump sizes.
Data sources
- DESNZ, Boiler Upgrade Scheme statistics, August 2026, Tables A1.3A and Q1.1A.
- Energy Systems Catapult for DESNZ, Electrification of Heat trial, heat pump performance report, December 2024.
- DESNZ, National Energy Efficiency Data-Framework 2026.
- Ofgem, energy price cap, October to December 2026.