Ground Source Heat Pump Cost in the UK: 2026 Prices

The latest quarter jumped because the systems were bigger. The median ground source heat pump paid in July to September 2026 was 15 kW, against 10.5 kW the quarter before and 12 to 13 kW in most quarters since 2022, and a bigger heat pump needs a longer ground loop. DESNZ also warns that the figures use the MCS certificates lodged at the time of analysis, so the latest quarter can still move as late certificates arrive. With only about 365 ground source installs a year carrying cost data, one quarter's median can swing by thousands of pounds. For a steadier comparison, the next section uses the full year 2025/26 by size.

Air source prices have barely moved over the same year: a median of £12,826 to £13,437 every quarter. If you are pricing a typical semi or terrace, our heat pump cost by house type guide covers air source in detail.

Small ground source systems cost more for each kW because much of the job does not shrink with the heat pump: the drilling rig or digger has to come either way, and the cylinder, controls, commissioning and certificate cost much the same. That is why a 6 to 8 kW system cost £21,702 in 2025/26 and a 12 to 14 kW one only £25,750.

Treat the bands with fewer than about 30 installs with care. The 10 to 12 kW band, at 21 installs, sits above the bigger 12 to 14 kW band, which reflects a small sample rather than a real price step. The 20 kW or more band covers the largest jobs; DESNZ leaves out anything recorded above 45 kW. Our heat pump size guide shows how the kW figure is worked out from a home's heat demand, and the same method applies to ground source.

Guide prices run below what installers actually recorded. MyJobQuote's 8 kW horizontal system at £16,000 is well under the scheme's 2025/26 medians of £21,702 for 6 to 8 kW and £21,541 for 8 to 10 kW, and its borehole price is about level with them. Use the guide figures for the gap between the two loop types, and the scheme figures for the total.

A horizontal loop needs space. Which? works from roughly 10 metres of trench for each kW of heat pump, and gives the example of a 3-bed new build of about 120 square metres needing two trenches of 30 to 40 metres. MyJobQuote puts the area at often 2 to 3 times the floor area of the house. The garden is dug up for a few days and then reinstated, so it suits a plot already facing landscaping or an extension.

A borehole needs only room for a drilling rig, but its cost depends on ground you cannot see. Drilling is charged by the metre, and the depth depends on the geology, so a quote with an estimated rather than surveyed depth can move once drilling starts. Larger homes may need two or three boreholes. Under MCS rules the installer must establish the ground's thermal conductivity before designing a borehole, from a thermo-geological assessment or British Geological Survey data, which is covered further down.

Ground source heat pumps are permitted development in England, with no conditions on size or noise, as our planning permission guide explains.

The case for ground source is efficiency in the coldest weather. The ground holds a far steadier temperature through the year than the air does, so a ground source heat pump is not drawing its heat from frosty winter air. In the government's Renewable Heat Premium Payment trial, ground source systems averaged a seasonal efficiency of 2.75 against 2.36 for air source, about 17% higher. Ground source also has no fan unit outside, which helps on a plot where an air source unit would sit close to a neighbour's window.

The case against is cost and disruption: about £13,476 more at the median, plus a dug-up garden or a drilling rig on the drive. For a typical semi or terrace without much land, air source is the practical choice. Ground source makes most sense on a large plot, in a self-build where the groundworks are happening anyway, or where an outdoor unit has nowhere acceptable to go. To price the air source alternative for your own home, the heat pump calculator works it out from your house type and insulation.

Why 3.25 for ground source. The government's Electrification of Heat trial, which gives our air source figure of 2.78, had too few ground source systems to give a reliable typical figure. The earlier Renewable Heat Premium Payment trial did: across 94 ground source and 297 air source systems monitored for a year, ground source averaged 2.75 and air source 2.36, a 17% lead. Applying that lead to today's air source median of 2.78 gives 3.24, which we round to 3.25, the figure our model already uses for the best tenth of air source systems. It is an estimate, not a measurement. Some guides quote 3.5 to 4.5, as Which? does; measured whole-system results in UK homes have come in lower.

At 3.25 a ground source heat pump beats gas even on a standard tariff: a kWh of heat costs 8.1p, against 8.86p from a gas boiler, while a typical air source system at 2.78 does not. On a heat pump tariff the same heat costs about 5.75p. See our heat pump tariffs guide for the tariffs that get you there.

The saving against air source is small next to the extra install cost. For a 4-bed detached house, which needs about 12 kW, ground source saves £128 a year on a heat pump tariff and £180 on a standard one. The scheme's 2025/26 medians put a 12 to 14 kW ground source system £10,384 above air source, so the running cost alone takes 58 to 81 years to pay it back. Against oil the picture changes: the same house saves £991 a year moving from oil to ground source on a heat pump tariff, and £408 moving from gas. Our heat pump running costs guide has the full air source comparison.

The grant is the same for ground source as for air source, so it covers a much smaller share of the bill: about 28% of the median ground source job against 58% of the median air source one. One grant is allowed per property. The installer applies and takes it off the invoice; our Boiler Upgrade Scheme guide walks through the steps.

Ground source grants go to a different kind of home from air source. Of the 1,603 paid since May 2022, 881, or 55%, went to homes with no previous heating system, which DESNZ says means a first heating system, for example in an eligible custom-build. Another 365 (23%) replaced oil and only 173 (11%) replaced gas. Self-built homes can qualify, while new builds still being built by a developer cannot, according to GOV.UK. If you are buying or running an off-gas home on oil, the £9,000 rate and the oil saving above make ground source easier to justify.

Heat pump installations carry 0% VAT until 31 March 2027, according to HMRC VAT Notice 708/6, and the costs above already reflect that. The scheme covers England and Wales only. In Scotland, GOV.UK points homeowners to Home Energy Scotland for a grant or an interest-free loan.

The standard says the fluid returning from the ground must settle above 0°C, with the ground recovering fully each year. A loop that is too short pulls the ground colder every winter, the heat pump works harder and its efficiency falls. So a cheap quote with less drilling or trench than the others is worth questioning, not just accepting.

When comparing quotes, ask each installer for the same things: the heat loss figure, the heat pump size, the metres of borehole or trench, the watts per metre and ground conductivity they designed to, whether the drilling depth is surveyed or estimated, and who removes the spoil. Ask too whether radiator upgrades are included, because ground source works best at low water temperatures. Our guides to radiator sizing and underfloor heating costs cover that side of the job.

Installed costs, sizes and grant counts from the DESNZ Boiler Upgrade Scheme statistics, September 2026, published 29 October 2026, Tables Q1.1A, A1.3A, 1.1 and 1.3; costs are self-reported by MCS installers and include the system, labour and VAT, before the grant. Borehole and trench prices from the MyJobQuote ground source heat pump cost guide, updated 9 September 2026, and trench and borehole sizes from Which?. Ground and air source efficiency from the RHPP detailed analysis report (DECC, re-issued March 2017) and the Electrification of Heat trial report. Ground loop design rules from MCS MIS 3005-D: 2025. Energy prices from the Ofgem price cap, October to December 2026; heat pump tariff as costed in our tariffs guide. Grant rules from GOV.UK. Full method on our methodology and data sources pages.