Every heat pump quote I see a client hand me carries two numbers that don’t look like they belong in the same document: an installed cost that can run past £13,000, and a government grant that knocks £7,500 straight off it before a penny changes hands. Both are genuine. Fully installed, most UK homes are looking at roughly £9,000–£16,000 for an air source heat pump in 2026 before any grant, and typically £1,500–£8,500 once the Boiler Upgrade Scheme has been deducted, with a typical three-bed home netting out somewhere around £5,000.
What moves that price is mostly straightforward: the size of pump your house needs, how much of your existing heating system has to change to suit it, and where you live. What moves it in ways a sales-led quote has less reason to dwell on is whether the house is actually ready for a heat pump without spending on the fabric first — and that’s the part worth getting an honest answer on before you sign anything.
I do the diagnosis end of retrofit, not the installation, so I’ve no heat pump to sell you and no commission riding on the answer. This is a straight read on what one costs in 2026, what the grant is actually worth, and when I’d tell a client to hold off.
The short answer
Prices below were checked on 22 July 2026, cross-referenced against Boiler Upgrade Scheme statistics published by Ofgem/DESNZ, current Checkatrade and HomeOwners Alliance cost data, and gov.uk grant guidance. As with most trades, my own patch of Kent, Sussex, Surrey and London tends to sit toward the upper end of these ranges.
| Property | Typical installed cost | After the £7,500 grant |
|---|---|---|
| Flat or small terrace, straightforward retrofit | £8,000–£11,000 | £500–£3,500 |
| 3-bed semi or detached — the average case | £11,000–£14,000 | £3,500–£6,500 |
| Larger/older detached, bigger pump, new radiators | £14,000–£18,000+ | £6,500–£10,500+ |
Government figures back the middle row directly: Boiler Upgrade Scheme statistics published in January 2026 put the average gross cost of an installed system at roughly £12,500–£13,400 for a typical 8kW unit — almost exactly the size a standard three-bed home needs. Worked through: a 3-bed semi quoted at £12,500 gross drops to £5,000 once the £7,500 grant is deducted from the installer’s invoice — you never see or handle the grant money yourself. Properties off the gas grid, heated by oil or LPG, currently qualify for £9,000 rather than £7,500 (more on that below), which would take the same £12,500 quote down to £3,500.
What drives the price
The size of pump you need. A heat pump is sized to your home’s calculated heat loss, not guessed from square footage. A well-insulated two-bed flat might need a 5–6kW unit; a large, older detached home can need 12kW or more. The unit itself typically costs £3,000–£7,000 depending on output and brand, before labour.
Labour and commissioning. A standard installation runs £2,000–£4,000 and takes two to four days — siting and plumbing the outdoor unit, running new pipework, fitting controls, and commissioning the system so it actually hits its design flow temperature rather than just switching on.
A hot water cylinder. Most heat pumps need one, even if your current boiler is a combi with no tank. Where there’s no existing cylinder or airing cupboard to reuse, add £500–£1,500 and, sometimes, a genuinely awkward conversation about where it’s going to live.
Radiators, or their absence. Heat pumps work best running at a lower flow temperature than a gas boiler, which usually means larger radiators — or, in a minority of jobs, none at all if the property already has generous emitters or underfloor heating. Upgrading radiators throughout an older home with small Victorian rads can add a genuinely significant sum, and it’s the item most likely to appear as a nasty surprise on a quote that started out looking competitive.
Location. As with most trades, the South East and London carry a premium over the national average, for the usual reasons — overheads, demand, and less room to manoeuvre plant on site.
The Boiler Upgrade Scheme, and the new £9,000 rate for oil and LPG homes
The Boiler Upgrade Scheme (BUS) is the government grant behind most of these numbers, run by Ofgem on behalf of DESNZ, and currently funded through to early 2028. It pays £7,500 towards an air source or ground source heat pump, or £5,000 towards a biomass boiler, provided the installer is MCS-certified and the product is on the MCS product list. It isn’t means-tested and doesn’t care about your council tax band, but it does exclude hybrid systems that keep a gas boiler running alongside the heat pump. As of 2026, an EPC recommending further insulation no longer blocks the grant, which removed one of the more common reasons applications used to fall over.
The genuinely new detail, and topical as I write this: from 21 July 2026 — yesterday — the grant rises to £9,000 for homes currently heated by oil or LPG with no mains gas connection, a £1,500 uplift confirmed by DESNZ and running until 31 March 2027. It’s aimed squarely at rural, off-grid properties, where the realistic alternative to a heat pump is usually a like-for-like oil boiler rather than a cheap gas one, and where the case for switching is often strongest. If that’s your situation, it’s worth timing the work to fall inside that window.
Separately, and worth factoring into any quote you’re comparing: installations are currently zero-rated for VAT under HMRC’s energy-saving materials relief, a 0% rate that runs until 31 March 2027 and then reverts to the 5% reduced rate, not full VAT. On a typical installed price, that’s worth somewhere between a few hundred and a couple of thousand pounds depending on the job — ask any installer to confirm it’s already applied rather than added back at invoice stage.
Is your house actually ready for one?
This is the section a sales-led quote tends to skip, and it’s where an independent assessment earns its fee. A heat pump run at a sensible, efficient flow temperature only performs well if the building can hold heat at that lower temperature — which means insulation and glazing standards genuinely matter, not as a box-ticking exercise but as the thing that decides whether your bills go down or up.
A survey of heat pump owners published in January 2026 found a striking two-thirds reporting their home was more expensive to heat than under their previous system, against roughly one in seven who found it cheaper. Read that carefully rather than as a verdict on the technology itself: the properties most likely to disappoint are the ones installed without a proper room-by-room heat loss calculation, running at too high a flow temperature to compensate for undersized radiators, in homes with real fabric problems the pump was never going to fix. A heat pump fitted into a genuinely well-insulated home, sized and commissioned properly, is a different proposition — and the running-cost comparisons that show heat pumps matching or beating gas tend to assume exactly that starting point.
The practical upshot: before you commit, get a proper heat loss calculation done room by room, not a rule-of-thumb estimate from floor area. Ask what flow temperature the system is designed to run at — the lower the better, ideally 35–45°C — and whether your radiators were sized to suit it or simply left as they were. If you’re on a solid-wall or older property with no cavity to fill, be honest with yourself about whether insulation work should come first, even if that means a less exciting quote this year and a better one next.
What I'd watch for in a quote
- An MCS-certified installer, checked directly. This isn’t optional if you want the grant, and it’s worth confirming the registration yourself on the MCS database rather than taking a business card’s word for it.
- A room-by-room heat loss survey, not a floor-area guess. If a quote arrives within a day of a fifteen-minute look round the house, ask what it’s actually based on.
- A stated design flow temperature. A good installer will give you the number and explain how the radiators or emitters were checked against it. If nobody mentions it, ask.
- The grant already deducted, not bolted on as a discount. The £7,500 (or £9,000) should reduce the invoice directly — it’s never paid to you to hand over yourself.
- Radiator and cylinder costs itemised up front. These are the two items most likely to inflate a headline price after survey, so get them confirmed before you sign, not after.
Questions I get asked
Will I need new radiators? Possibly, particularly in an older home with small Victorian-sized rads. A heat pump running at a lower flow temperature needs a larger surface area to release the same heat, so undersized radiators either get upgraded or the system runs hotter and less efficiently than it should. A proper survey will identify which rooms, if any, need it — rarely the whole house.
Can I get the £9,000 grant if I’m on mains gas? No. The £1,500 uplift is specifically for properties with no mains gas connection, currently heated by oil or LPG. Mains gas properties remain on the standard £7,500.
Is a heat pump actually cheaper to run than my gas boiler? Genuinely close, and it depends on your tariff and your home’s efficiency more than the technology itself. On a standard electricity tariff, running costs sit roughly at parity with gas. On a dedicated heat-pump or off-peak tariff, most cost data puts a heat pump £200–£400 a year cheaper. Good insulation and a properly designed system matter more to that number than which brand you choose.
Do I need planning permission? Almost never for a standard domestic installation — it’s usually permitted development, subject to size and distance-from-boundary limits. Listed buildings and some conservation areas are the exception; check before you commit if either applies to you.
If you’re weighing up a heat pump and want an honest read on whether your house is ready for one before you commit to a quote, that’s exactly the kind of question a PAS 2035 retrofit assessment is built to answer — heat loss, fabric, ventilation and the right sequencing of work, from someone with nothing to sell you afterwards. It often pairs well with an up-to-date EPC if you’re also thinking about a mortgage, sale or MEES compliance. Call 07946 618203 or get in touch and I’ll give you a straight answer on where to start.
Small print. This guide is general information, not advice on a specific property, and it doesn’t replace a proper heat loss survey for your home. Prices were researched and correct to the best of my knowledge on 22 July 2026; costs, grants and VAT rules move and vary by region and property. Always get at least three written quotes before instructing.