Heat pump prices confuse people because the internet quotes the unit price and installers quote the job price. The unit is £3,000–£6,000 of hardware; the job is a heating system — design, cylinder, radiators, electrics, labour, commissioning and paperwork. This guide prices the job, because that's the number you'll actually pay, and then subtracts the grants, because in 2026 almost nobody pays the gross figure.
How Much Does an Installed Heat Pump Cost by Property Type?
In 2026, a fully installed air-to-water heat pump system in Buckinghamshire costs £8,500–£16,000 before grants: £8,500–£10,000 for a 2-bed cottage, £9,000–£11,000 for a 3-bed semi, £10,500–£13,000 for a 4-bed detached, and £12,500–£16,000 for a large farmhouse. Grants remove £2,500–£9,000 of that.
| Property | Typical unit size | Installed price |
|---|---|---|
| 2-bed cottage or terrace | 4–6 kW | £8,500–£10,000 |
| 3-bed semi | 5–8 kW | £9,000–£11,000 |
| 4-bed detached | 8–12 kW | £10,500–£13,000 |
| 5-bed farmhouse / large rural | 12–16 kW | £12,500–£16,000 |
| Flat / small home, air-to-air route | 1–3 indoor units | £2,500–£7,000 |
Solid-wall period properties can sit above their band — bigger emitters and sometimes a high-temperature unit. The survey settles it.
What Pushes the Price Up — or Down?
The big movers are radiator swaps (£250–£450 each), heat pump size (an 8 kW to 12 kW step adds £1,000–£1,500), cylinder placement, pipe-run length and groundworks. Good insulation and existing underfloor heating pull the price down. The biggest risk to your wallet is a quote produced without a survey.
Up: more radiators needing upsizing (each swap is roughly £250–£450 fitted); no existing cylinder space, forcing a cupboard build or loft install; long pipe runs between the outdoor unit and plant location; microbore pipework that needs upgrading; a high-temperature unit for a hard-to-insulate house; consumer unit or supply upgrades in older properties. Down: underfloor heating already in place; a recent system boiler setup with a usable cylinder and pump position; good insulation, which shrinks the unit size — the difference between an 8 kW and a 12 kW unit is around £1,000–£1,500 before it touches anything else; and flexible siting, which shortens pipework and labour.
Siting and groundworks are the quiet variable. An outdoor unit that lands on an existing patio next to the plant room costs nothing extra; one that needs a concrete base, a trench for pipe runs, or crane access over a garage adds £300–£1,200. Since the one-metre boundary rule was scrapped in England (May 2025), units can sit closer to boundaries provided the noise assessment passes, which frequently shortens pipe runs and saves real money on semis and cottages with narrow side access.
The pricing red flag to watch for — from anyone — is a quote produced without a heat loss survey. It means the radiator schedule is a guess, and guesses surface later as extras. Our air source heat pump page sets out exactly what a survey-led quote includes, line by line. And if the air-to-water numbers don't fit your budget, remember the cheaper door: a single-zone air-to-air system starts at £2,500 before its own £2,500 grant.
The Grant Maths, Worked Through
Three real-shaped scenarios, using the Boiler Upgrade Scheme rates that apply in 2026. The grant comes off the invoice before you pay — these net figures are cash-out-of-pocket:
| Installed price | £10,400 |
|---|---|
| BUS grant (gas home) | −£7,500 |
| VAT | £0 |
| You pay | £2,900 |
| Installed price (incl. tank decommissioning) | £12,300 |
|---|---|
| BUS grant (oil home, uplifted) | −£9,000 |
| VAT | £0 |
| You pay | £3,300 |
| Installed price | £3,200 |
|---|---|
| BUS grant (air-to-air) | −£2,500 |
| VAT | £0 |
| You pay | £700 |
Context for scenario 2, because it's the common one around here: a like-for-like oil boiler replacement runs £4,000–£6,000 with no grant at all. From July 2026, the heat pump is not the expensive option for an oil-heated home — it's the cheap one, and it comes with lower running costs on top. The whole oil journey, tank removal included, is on our oil boiler replacement page, and the timing rules for the £9,000 rate are in the £9,000 grant guide.
How Does It Compare With Just Replacing the Boiler?
After the 2026 grants, oil-heated homes typically pay £1,000–£5,000 for a heat pump against £4,000–£6,000 for a like-for-like oil boiler — the heat pump is now often the cheaper purchase, and then cheaper to run. On mains gas it's close to a tie upfront.
The fair comparison for most people isn't "heat pump vs nothing" — it's "heat pump vs the boiler I'd otherwise have to buy". A new gas combi installed costs £2,500–£4,000; a new oil boiler £4,000–£6,000; a new LPG boiler £3,000–£4,500 — none with a penny of grant support. Put those next to the net heat pump figures above and the picture inverts for off-gas homes: the oil-heated 4-bed pays £3,300 for a heat pump or around £5,000 for another oil boiler, and the heat pump then costs less to run every year after. For gas homes the boiler is still cheaper upfront (£3,000 vs £2,900 is a coin flip; smaller gas jobs undercut it) — which is why we tell gas households the running-cost truth on the running costs page and let the maths decide.
One more lens: lifetime. A heat pump's 15–20 year service life spans roughly one and a half boiler lifetimes, so a like-for-like whole-life comparison should price the boiler route at the boiler plus half its replacement. Almost nobody sells heating that way, which is exactly why it's worth doing the sum yourself.
What About Costs After Installation?
Budget for an annual service (£150–£250, comparable to a boiler service and required by most warranties) and electricity per the running-cost figures in our running costs guide. There's no fuel storage, no tank insurance, no chimney sweep and no landlord gas safety certificate. Manufacturer warranties run 5–7 years on the units we fit; realistic service life is 15–20 years against 10–15 for a boiler.
Are There Hidden Costs to Budget For?
Three, all small and all knowable in advance: an EPC assessment if yours has expired (£60–£120), a loft insulation top-up if the EPC demands it for the grant (£300–£600, and it cuts your bills anyway), and redecoration where old pipework is removed — we make good to a paint-ready finish; repainting is yours.
The network operator application for connecting the unit is handled by us and free at domestic sizes. What shouldn't appear afterwards, ever: "unexpected" radiator or pipework charges. Those are the survey's job to find first, and a fixed quote means fixed.
Cost Questions
Why do quotes for the same house vary by thousands?
Usually scope, not greed: one quote includes radiator changes, cylinder and making-good, another leaves them as "allowances". Compare the radiator schedule, the cylinder spec, the design SCOP and what happens to the old system. A cheaper headline that excludes half the job is the most expensive quote on the table.
Can I finance the amount after the grant?
Net costs of £1,000–£5,000 put a heat pump inside normal home-improvement financing — bank products and green additional-borrowing mortgage options exist at several lenders. We're installers, not brokers, so we'll give you the fixed number to take to whoever finances it.
Is it worth paying more for a bigger unit "to be safe"?
No — oversizing is the classic expensive mistake. A too-big unit costs more upfront, then short-cycles for fifteen years, wearing components and missing its SCOP. The heat loss calculation exists precisely so you buy the right kilowatts, not the reassuring ones.
Is a ground source heat pump worth the extra cost?
Rarely, for a retrofit. Ground source runs £18,000–£30,000+ installed because of borehole or trench groundworks, attracts the same £7,500/£9,000 grant as air source, and gains a point or so of efficiency that takes decades to repay the difference. It earns its keep on large rural plots with very high heat demand, or new builds trenching anyway — for everyone else, air source wins the maths.
Do prices rise once the £9,000 window opens?
Demand will certainly rise, and with it lead times; reputable installers' prices are driven by equipment and labour, not grant harvesting. Our protection either way: your quote is fixed from the survey, and booking before the rush secures both the price and the queue position.
Get a Fixed Number Instead of a Range
Ranges are for guides; your house deserves a figure. A free heat loss survey produces a fixed, itemised quote with the right grant — £7,500, £9,000 or £2,500 — already deducted. Check what applies to you on the Boiler Upgrade Scheme hub, then get the number.