What it really costs in 2026, before and after the grant, and the specific things that move the number up or down on your property.
Tell us about your property and an MCS-certified engineer will be in touch, usually the same working day.
| System | Installed cost | Grant | Net |
|---|---|---|---|
| Air source, 2–3 bed | £8,000 – £11,000 | £7,500 | £500 – £3,500 |
| Air source, 3–4 bed | £9,000 – £14,000 | £7,500 | £1,500 – £6,500 |
| Air source, large / period | £14,000 – £20,000+ | £7,500 | £6,500 – £12,500+ |
| Ground source, horizontal | £20,000 – £28,000 | £7,500 | £12,500 – £20,500 |
| Ground source, borehole | £25,000 – £35,000+ | £7,500 | £17,500 – £27,500+ |
| Air to air, single room | £2,000 – £3,500 | £2,500 | Often near zero |
| Air to air, multi room | £5,000 – £9,000 | £2,500 | £2,500 – £6,500 |
Installation is zero rated for VAT, so these are the figures you pay. If you are off the gas grid on oil, the grant rises to £9,000 for installations between 21 July 2026 and 31 March 2027, which takes another £1,500 off every net figure above.
People assume the heat pump is most of the cost. On a typical £11,000 installation it is usually under half.
| Element | Typical share |
|---|---|
| Heat pump unit | £3,500 – £5,500 |
| Hot water cylinder | £1,000 – £2,000 |
| Radiator upsizing | £0 – £3,500 |
| Pipework, fittings and controls | £1,200 – £2,500 |
| Labour, survey and design | £2,000 – £3,500 |
| Electrical works | £300 – £1,200 |
| Groundworks (ground source only) | £8,000 – £20,000+ |
A well-designed system running at 35 to 45°C with a seasonal efficiency around 3.5 to 4 will usually be comparable to mains gas and substantially cheaper than oil, LPG or direct electric. Against oil in particular, which is what most of the Weald villages around Wadhurst, Frant and Mayfield are running, the saving is real and consistent.
The uncomfortable truth of this industry is that a badly designed heat pump running at 55°C or above can cost more to run than the boiler it replaced. That is a design failure, not a technology failure, and it is why we will not quote without surveying.
An air source heat pump on an average UK house costs £8,000 to £14,000 installed before grant. After the £7,500 Boiler Upgrade Scheme grant, most households pay a net £1,500 to £6,500. Ground source runs £20,000 to £35,000 before the same grant.
Around £11,000 before grant for a typical three or four bedroom house with an air source system, which is roughly £3,500 net after the £7,500 grant. Averages hide a lot though: the same house with adequate radiators against one needing eight replaced can differ by £4,000.
Because the work behind the unit varies enormously. The heat pump itself is a minority of the cost. Radiator upsizing, pipework routes, cylinder installation, electrical supply upgrades and making good account for most of the difference between two quotes on the same street.
It depends on the flow temperature achieved and on the electricity to gas price ratio. A system running at 35 to 45°C with a seasonal efficiency around 3.5 is usually comparable to or slightly cheaper than mains gas, and clearly cheaper than oil, LPG or electric heating. A poorly designed system running at 55°C or higher can cost more than the boiler it replaced, which is why the design matters more than the brand.
There should not be, and there are none in our quotes. The things that catch people out elsewhere are cylinder installation where none existed, radiator changes, electrical supply upgrades, and reinstatement after pipework. All of those are identified at the survey and priced before you commit.
Get a free, no-obligation quote for heat pump installation in Tunbridge Wells, with the grant deducted so you see the real figure. We come back to you the same working day.