An installed air source heat pump for a three-bedroom semi or small detached house typically costs £12,000–£15,500, as a guide price including VAT, before any grant. Smaller homes start from about £9,500, and larger or older houses cost more. In England and Wales the Boiler Upgrade Scheme grant of £7,500 comes off that price; Scotland and Northern Ireland have their own arrangements.
This guide sets out typical ranges by home size, what a full installation includes, the extras that can add to the bill, and how to compare quotes on a like-for-like basis. Every figure is a guide: your price is fixed in a written quote after a home survey and room-by-room heat loss calculation.
What does an air source heat pump cost by home size?
Guide prices for a full air-to-water system range from about £9,500–£12,500 for a small flat or terrace to £16,500–£22,500 for a large or older house. The table shows typical installed ranges including VAT, the usual size of unit, and the figure after the standard Boiler Upgrade Scheme grant, which covers England and Wales only.
| Home | Typical size | Guide price, installed inc VAT | After the grant (England and Wales) |
|---|---|---|---|
| 1–2 bedroom flat or small terrace | 4–5 kW | £9,500–£12,500 | £2,000–£5,000 |
| 2–3 bedroom terrace or semi | 5–7 kW | £10,500–£13,500 | £3,000–£6,000 |
| 3 bedroom semi or small detached | 6–9 kW | £12,000–£15,500 | £4,500–£8,000 |
| 4 bedroom detached | 8–12 kW | £14,000–£18,000 | £6,500–£10,500 |
| 5+ bedroom or larger older house | 11–16 kW | £16,500–£22,500 | £9,000–£15,000 |
These are guide prices, not quotes. Across the UK, including Northern Ireland, the installation of a heat pump is zero-rated for VAT until 31 March 2027, and the ranges reflect that. The after-grant column assumes the standard £7,500 grant. If your heat pump replaces oil or LPG heating and is installed between 21 July 2026 and 31 March 2027, the grant is £9,000, so the balance is lower again.
Home size is only a starting point. Two houses with the same number of bedrooms can need quite different systems, depending on insulation, window area, wall construction and how warm you like each room.
What is included in the price of a heat pump installation?
A full air-to-water installation price normally covers the equipment, the labour and the paperwork needed to hand over a working, registered system.
- A home survey and room-by-room heat loss calculation to size the system
- The outdoor heat pump unit, mounted on a base or wall brackets
- A heat pump hot water cylinder, because there is no combi-style equivalent
- Controls, including weather compensation, and any hydraulic parts the design needs
- Connection to your existing heating pipework, with minor alterations
- The electrical connection, and notifying the electricity network operator where required
- Removing the old boiler, where agreed
- Commissioning, a handover on using the controls, and MCS registration with a certificate
Manufacturer warranties pass to you — the length depends on the make and model — and our workmanship guarantee is set out in writing in your quote.
What extra costs can come with a heat pump?
The main extras are radiators, pipework, the cylinder and underfloor heating, and whether you need any of them depends on what your survey finds.
| Possible extra | Typical guide price, installed inc VAT |
|---|---|
| Replacement radiator sized for a heat pump (each) | £250–£450 |
| Upgrade of about 10 radiators | £2,000–£5,000 |
| Pipework upgrade, such as microbore to larger bore | £1,500–£3,500 |
| Heat pump hot water cylinder, where priced separately | £1,200–£2,200 |
| Wet underfloor heating, one room | £1,500–£3,500 |
| Wet underfloor heating, whole ground floor | £5,000–£15,000 |
| High-temperature unit, extra over a standard unit | £1,500–£3,000 |
Radiators are the most common extra. Heat pumps run most efficiently at low flow temperatures of around 35–50°C, so some rooms may need a larger radiator to stay warm. It is rarely every room: the heat loss calculation shows which ones fall short. Our guide to radiators for heat pumps explains how this is worked out.
Narrow microbore pipes can restrict the higher water flow a heat pump needs, and some homes need new pipe runs to the cylinder. Underfloor heating suits heat pumps well, but laying it under an existing floor is a bigger job, so most people consider it during a renovation or extension.
What grants are there for heat pumps in each UK nation?
Grant support depends on where you live: the Boiler Upgrade Scheme covers England and Wales, Home Energy Scotland funds homes in Scotland, and Northern Ireland has no dedicated heat pump grant for homeowners at present.
| Nation | Main support | Key point |
|---|---|---|
| England | Boiler Upgrade Scheme grant of £7,500, or £9,000 when replacing oil or LPG (21 July 2026 to 31 March 2027) | The MCS-certified installer applies and deducts it from your quote |
| Wales | Boiler Upgrade Scheme, on the same terms as England | The MCS-certified installer applies and deducts it from your quote |
| Scotland | Home Energy Scotland grant of up to £7,500, plus up to £1,500 for eligible rural and island homes, and an optional interest-free loan of up to £7,500 | You need a written funding offer before work starts |
| Northern Ireland | No dedicated heat pump grant for homeowners at present | Heat pumps have sometimes been funded through the Northern Ireland Sustainable Energy Programme |
Home Energy Scotland funding is first come, first served and needs an MCS-certified installer and products, so wait for your written offer before you agree a start date. Our heat pump grants by nation guide covers each scheme in more detail.
What makes a heat pump cost more or less?
The biggest driver of cost is the heat loss of your home, because it sets the size of the unit and how much of your heating system has to change.
- Heat loss: a draughty or poorly insulated home needs a larger unit, and often larger radiators
- Radiators and pipework: reusing what you have keeps the price down; replacing several adds to it
- Cylinder position: an existing airing cupboard is simpler than finding new space
- Outdoor unit siting: a short pipe run to a level base costs less than a long run or a raised platform
- Electrics: some homes need consumer unit work or a supply check with the network operator
- Unit type: a high-temperature model, a split system or a hybrid each changes the price
- Access: scaffolding, restricted parking or a remote location can add labour and travel
Some costs are worth paying even though they raise the quote. A well-designed system with the right radiators runs at a lower flow temperature, which usually means lower running costs for its whole life. A quote that looks low because it skips the radiator upgrades may cost more to run.
How do I compare heat pump quotes?
Compare heat pump quotes on the design behind them, not just the total, because two quotes for the same house can be sized very differently.
- Is the size based on a room-by-room heat loss calculation, and does the quote state the result in kW?
- What design flow temperature and estimated SCOP (seasonal efficiency) is it based on?
- Which radiators are being changed, and which are kept?
- Is the cylinder size stated, and does it suit your household's hot water use?
- Does it name the MCS-certified installer for your job, and show any grant deduction that applies where you live?
- What is included for electrics, making good and removing the old boiler?
- Which manufacturer warranty applies to the make and model, and what workmanship guarantee is offered in writing?
Nothing is ordered until you accept a written quote. Your rights under the Consumer Rights Act 2015 and the Consumer Contracts Regulations 2013 apply, including the right to cancel within 14 days if you agree the contract away from our premises (if you ask us to start sooner and then cancel, you pay only for work done up to that point). You can request a free home survey and heat loss calculation for an installation enquiry.
Questions
Is the heat pump price on this page the final price?
No. The figures are guide prices, installed and including VAT, based on typical homes. Your final price is fixed in a written quote after a survey and room-by-room heat loss calculation, which shows the size of unit, the radiators and pipework that need changing, and the cylinder. Nothing is ordered until you accept that quote.
Does the Boiler Upgrade Scheme grant cover the whole UK?
No. The Boiler Upgrade Scheme covers England and Wales only. Homes in Scotland can apply to Home Energy Scotland for a grant and an optional interest-free loan, and Northern Ireland has no dedicated heat pump grant for homeowners at present. In England and Wales the MCS-certified installer applies for the grant and deducts it from your quote.
Do I have to replace all my radiators?
Usually not. Heat pumps run at lower water temperatures than most boilers, so a radiator that is too small for its room at those temperatures may need replacing, but many existing radiators can stay. The heat loss calculation compares each room's heat loss with its radiator's output. A replacement radiator is a typical £250–£450 each, fitted, as a guide price including VAT.
Why do quotes for the same house vary so much?
Quotes vary mainly because of sizing and scope. One quote may be sized from a full room-by-room heat loss calculation and include the radiators needed for a low flow temperature, while another may price a unit alone. Check the stated heat loss in kW, the design flow temperature, the radiators included and the named MCS-certified installer before comparing totals.
Sources
- Apply for the Boiler Upgrade Scheme – GOV.UK
- Boiler Upgrade Scheme – Ofgem
- Home Energy Scotland
- Air source heat pumps – Energy Saving Trust
- MCS (Microgeneration Certification Scheme)
Scheme figures and price cap rates checked October 2026.