Air source heat pump cost
Checkatrade’s May 2026 air source heat pump guide and August 2026 boiler-replacement guide give these UK ballparks (supply and installation, before BUS):
| System | Typical range | Average / note |
|---|---|---|
| Air-to-water (replace boiler) | £11,000–£20,000 | ~£15,000 |
| Air-to-water unit supply only | £5,000–£9,000 | ~£7,000 (5–17 kW band) |
| Air-to-water install only | £6,000–£11,000 | ~£8,000 |
| Air-to-air (5 kW) | £2,000–£4,000 | ~£3,000 (no hot water) |
| Upgrade ~10 radiators | £2,000–£5,000 | ~£3,000 |
| Underfloor heating | £5,000–£15,000 | ~£10,000 |
Headline “£3,000–£15,000” ranges mix air-to-air and air-to-water. For whole-house heating and hot water, plan on the air-to-water five-figure band unless your installer demonstrates otherwise.
Heat pump cost UK after the grant
Eligible installations in England and Wales can receive a Boiler Upgrade Scheme grant paid to the MCS installer and deducted from your invoice. After a £7,500 air-to-water grant, a £15,000 average install becomes about £7,500 net before radiator or insulation upgrades. A £18,000 quote becomes about £10,500 net, and so on.
VAT treatment for qualifying heat pumps can further change the cash price — confirm on the quote. BUS does not cover hybrid heat-pump-plus-gas-boiler systems.
Boiler Upgrade Scheme amounts (verified)
Per GOV.UK and Ofgem (checked November 2026):
- £7,500 — air-to-water heat pump (and ground source / water source in the scheme rules).
- £7,500 — ground source heat pumps (including shared ground loops within capacity limits).
- £2,500 — air-to-air heat pumps.
- £5,000 — biomass boilers (limited eligibility).
- £9,000 — air-to-water or ground source in eligible off-gas-grid properties replacing oil or LPG heating, for applications properly made from 21 July 2026 until 31 March 2027 (an extra £1,500 versus the standard £7,500).
One grant per property. Capacity caps apply (for example 45 kWth for many individual systems — see GOV.UK). Your installer confirms eligibility; rules can change, so re-check gov.uk before you sign.
Heat pump vs gas boiler
A like-for-like gas combi replacement often costs £2,500–£4,000 (Checkatrade, October 2026). An air-to-water heat pump is a different project: outdoor unit space, electrical supply, cylinder in many homes, lower flow temperatures and commissioning. Even after £7,500 BUS support, expect a higher upfront bill than a boiler swap, with the payback coming from efficiency, comfort at design temperatures, and future fuel-policy risk rather than a one-year saving guarantee.
- Choose a boiler for lowest capital cost on a failed combi when you are not ready to upgrade emitters.
- Choose a heat pump when fabric efficiency is decent (or will be upgraded), you can site the outdoor unit, and an MCS installer models a sensible SCOP.
- Do not assume BUS stacks with every other local grant — ask the installer which schemes can combine.
Worked example: semi after BUS
Worked example
On-gas semi-detached house in England. MCS quote for air-to-water supply and install: £16,000. BUS grant £7,500 → £8,500 net for the heat pump package. Installer also recommends upsizing eight radiators at £2,800 and a cylinder upgrade already included in the £16,000. No underfloor heating.
If the same home were off the gas grid replacing an oil boiler within the uplift window, the grant could be £9,000, taking the same £16,000 quote to £7,000 net before radiator work.
Answer: £16,000 − £7,500 = £8,500 net on-gas (plus £2,800 radiators → £11,300). Off-gas oil/LPG uplift: £16,000 − £9,000 = £7,000 net before emitters.
Radiators, insulation and quotes
- Insist on a heat-loss survey. Quotes without room-by-room losses are guesses.
- Size emitters for the design flow temperature. Use the Radiator BTU Calculator as a homeowner check, then let the MCS designer confirm ΔT.
- Budget fabric upgrades where cheap. Checkatrade lists cavity wall roughly £500–£3,000 and loft blanket work £500–£2,000 in related guides — often better value than oversized plant.
- Compare three MCS quotes with the BUS amount shown as a line item.
- Plan noise and planning. Many external units are permitted development within limits, but flats, conservation areas and tight boundaries need an early check.
For fossil-fuel replacement pricing without a heat pump, see the new boiler cost guide. When you are ready to test radiator sizes, open the Radiator BTU Calculator.
What the quote should include
A serious MCS quote should show more than a single bottom line. Ask for:
- Heat-loss report by room and the design outdoor temperature used.
- Emitter schedule showing which radiators or UFH zones change.
- Cylinder size and whether hot-water demand was measured or assumed.
- Electrical works — consumer-unit space, isolation, and any supply upgrade.
- BUS grant line with the category (£7,500 or £9,000) and confirmation you are not double-counting VAT messages.
- Aftercare — commissioning handover, MCS certificate, and servicing expectations.
Air-to-air systems look cheap at around £3,000 average supply-and-install, but they do not provide domestic hot water. If you keep an immersion or a separate water heater, include that running cost in the comparison. Air-to-water is the fair comparator against a gas combi for most houses.
Running costs and expectations
Seasonal performance depends on weather, flow temperature, hot-water habits and how leaky the fabric is. Installers should quote an estimated SCOP and annual kWh — treat marketing “cuts bills in half” claims with caution unless they are tied to your survey. Homes that currently rely on oil or LPG often see clearer fuel-bill movement than efficient gas homes, which is one reason the temporary £9,000 off-gas uplift exists for oil/LPG replacements.
Noise, plume and neighbour outlook matter. Place the outdoor unit on a stable base with manufacturer clearances, not in a sealed alley that kills airflow. Planning Portal guidance and local advice still apply for some locations even when many householder heat pumps are permitted development within limits.
If the survey says you need major fabric work first, sequence insulation before or with the heat pump rather than blaming the machine for a cold bay window. Cheap cavity or loft top-ups listed in national cost guides (often low thousands of pounds) can reduce the plant size you buy. Re-check grant amounts on GOV.UK before you pay a deposit — scheme values and eligibility windows are set by regulation and do change.
Off-gas uplift in practice
The £9,000 figure is not a universal heat-pump bonus. GOV.UK describes it as an additional £1,500 on top of the standard £7,500 where the property is heated by oil or LPG and has no mains gas connection, available until March 2027. Ofgem’s property-owner guidance ties the uplifted £9,000 rate to applications properly made from 21 July 2026 to 31 March 2027 for eligible off-gas oil or LPG replacements with air-to-water or ground source heat pumps.
Your installer must evidence eligibility. If you are off-gas but replacing coal, electric storage heaters or another system category, check the approved grant table — some categories remain at £7,500 even off-grid. Do not market your project to yourself at £9,000 until the MCS firm confirms the category in writing on the quote.
Keep paperwork: MCS certificate, BUS voucher or grant reference, commissioning checklist and emitter schedule. Future buyers and EPC assessors will ask how the system was specified. A heat pump installed without adequate emitters is the fast route to comfort complaints and unfair blame on the technology.
If a gas boiler is genuinely the short-term answer, budget it properly with a Gas Safe engineer and revisit heat pumps when fabric and capital align — see the new boiler cost guide for current swap ranges.
Frequently Asked Questions
How much does an air source heat pump cost in the UK?
Checkatrade’s 2026 guides put supply and installation typically between £3,000 and £15,000 overall, with air-to-air around £3,000 and air-to-water often averaging about £15,000 (commonly £11,000–£20,000 when replacing a boiler). Extras for radiators, pipework and insulation are separate.
How much is the Boiler Upgrade Scheme grant for a heat pump?
GOV.UK and Ofgem list £7,500 for eligible air-to-water (and ground source) heat pumps in England and Wales. Until March 2027, an uplift to £9,000 applies for eligible off-gas properties replacing oil or LPG heating (applications properly made from 21 July 2026). Air-to-air is £2,500. Hybrids are not eligible.
Who applies for the BUS grant?
Your MCS-certified installer applies and deducts the grant from your quote. You do not claim the money yourself as a rebate.
Is a heat pump cheaper than a new gas boiler?
Upfront, no — a gas combi replacement is often £2,500–£4,000, while an air-to-water heat pump is usually five figures before grant. After a £7,500 BUS grant, many air-to-water projects land closer to a mid-teens net cost before radiator upgrades, still above a simple boiler swap.
Do I need bigger radiators for a heat pump?
Often yes. Heat pumps run at lower flow temperatures, so existing radiators may need upsizing. Checkatrade lists roughly £2,000–£5,000 to upgrade around 10 radiators. Size rooms with a BTU calculator at the design ΔT your installer specifies.
Get local quotes
Compare MCS-certified installers and ask for the BUS deduction on the quote.
UK: CheckatradeSources
- GOV.UK — Boiler Upgrade Scheme: what you can get — £7,500 ASHP/GSHP; £2,500 air-to-air; £5,000 biomass; £9,000 oil/LPG off-gas uplift until March 2027.
- GOV.UK — Notice of approved BUS grant values — Statutory grant categories effective from 21 July 2026.
- Ofgem — BUS for property owners — Installer claims the grant; MCS certification required.
- Checkatrade — Air source heat pump costs 2026 — £3k–£15k overall; air-to-water ~£15k average; radiator and insulation extras.
- Checkatrade — Replace boiler with heat pump — Air-to-water £11,000–£20,000 supply and install average £15,000.
When you are ready to estimate materials or cost for your project, open the Radiator BTU Calculator and enter your measurements.