A typical air-source install in 2026 runs £11,000 to £16,500 gross. The Boiler Upgrade Scheme voucher of £7,500 brings that to £3,500–£9,000 net. A like-for-like new gas boiler on the same house is £3,500–£4,500. Once the grant is genuinely on, a heat pump is now within striking distance of a new combi on day-one cost for most homes. This page is the straight version, with the £7,500 properly taken off rather than waved about.
That's the headline. The quote you actually get depends on how your house is put together — which is why we always say: don't trust any heat pump number until a surveyor has been on your doorstep for 45 minutes.
Typical 2026 install prices by home size
| Home size | ASHP capacity | Gross cost 2026 | After £7,500 BUS | Best fit |
|---|---|---|---|---|
| 1-2 bed flat / bungalow | 5-7 kW | £10,500 - £13,000 | £3,000 - £5,500 | Smaller, well-insulated homes |
| 3 bed semi | 7-9 kW | £11,500 - £14,500 | £4,000 - £7,000 | Standard UK family home |
| 4 bed detached | 9-12 kW | £13,000 - £16,500 | £5,500 - £9,000 | Larger or older detached |
| Large or poorly insulated | 12-16 kW | £15,500 - £20,000 | £8,000 - £12,500 | Pre-1930 or solid-wall homes |
The five things that can swing a quote by £4,000
- Radiator size. If your existing rads are undersized for the lower flow temperatures a heat pump runs at, you'll need four to eight of them upgraded at £180–£280 each.
- Hot-water cylinder. Most homes need a 200–250L unvented cylinder added — around £1,200 fitted.
- Outdoor unit siting. If the unit has to clear a Permitted Development noise distance or sit on a flat-roof bracket, add £400–£900.
- Pipe run. Anything over 6 metres of refrigerant-grade copper on the outdoor side noticeably changes the cost.
- Heat-loss survey. Required by MCS. We include ours free; some installers charge £350–£500 separately. Ask before you sign.
Running costs against gas — the real maths
A modern ASHP runs at a Seasonal Coefficient of Performance (SCOP) of 3.5–4.2 in a typical UK home. That means for every 1 kWh of electricity in, you get 3.5–4.2 kWh of heat out. At 2026 average tariffs — 28p/kWh electric, 7p/kWh gas — the per-unit-of-useful-heat cost works out roughly as: gas 8p/kWh, ASHP 7–8p/kWh on a flat tariff, or 4–6p/kWh on a heat-pump-optimised tariff like Octopus Cosy or Eon Next Drive.
What that means in plain English: on the right tariff, you'll pay 20–40% less to heat the home than the equivalent gas system. On a standard flat tariff, you'll pay about the same — and the win is the 75% carbon reduction rather than a bill saving. The tariff you pick after install matters more than the kit itself. Most installers won't mention it; it's easily the most commercially important thing on the page.
Who qualifies for the £7,500 BUS voucher
- Property is in England or Wales (Scotland has its own Home Energy Scotland funding).
- Valid EPC less than 10 years old.
- No open loft or cavity insulation recommendations on the EPC (insulation can be installed alongside the heat pump — see below).
- Domestic property, owner-occupied or privately rented.
- Replacing fossil fuel (gas, oil, LPG) or electric direct heating. Not eligible as a like-for-like heat-pump replacement.
The saving people miss: stacking BUS with ECO4
Households that qualify for ECO4 (means-tested grant, or a property at EPC D or below) can fund the loft and cavity insulation that makes the heat pump work properly under that scheme separately. Typically £1,500–£4,000 off the total package. We routinely stack BUS with ECO4 (and LA Flex on top where it applies) on the same property in the same diary week. For a fair share of our customers it means zero-cost insulation plus a £7,500-discounted heat pump — full fabric-first retrofit, one project.
Why some heat pump quotes look suspiciously cheap
A £6,000 net heat pump price almost always hides something: undersized pump, no cylinder upgrade, no radiator survey, no MCS certification. The system runs, but it cycles constantly, the customer hates the result, and the warranty voids inside 18 months. Before you sign, ask for three specific things: a written room-by-room heat-loss calculation, the installer's MCS number (search it on the public register), and a manufacturer warranty of at least seven years.
Check what your house actually qualifies for with a free MCS-spec heat pump quote, full heat-loss survey, and an honest BUS-plus-ECO4 stack check on the day. Book online or ring 0800 229 4094. The number on the quote is the number you pay.
Want to find out how much you could save?
Book a free 45-minute survey. We’ll check every active grant, measure every wall, and write you a plan. Yours to keep whether you book or not.
The plan is yours to keep. Take it to two other installers if you like.