How Much Does a Ground Source Heat Pump Cost in 2026?
A ground source heat pump installation in the UK typically costs between £18,000 and £45,000 before the Government grant. After the £7,500 Boiler Upgrade Scheme grant, you're looking at £10,500 to £37,500 depending on your property size, ground conditions, and system design.
That's a wide range, so let's break it down so you can understand what drives the cost and how to get the best value.
What's Included in the Cost?
A ground source heat pump installation has three main cost components:
- The heat pump unit — £5,000 to £12,000 depending on capacity (kW output) and brand. Thermal Earth installs MasterTherm heat pumps, which are manufactured in the Czech Republic and offer some of the highest COP ratings on the market
- Ground collector — this is the biggest variable. Boreholes cost more than horizontal trenches but need far less garden space
- Internal works — hot water cylinder, pipework connections, controls, and commissioning. Typically £3,000 to £6,000
Borehole vs Horizontal Trench — Cost Comparison
The type of ground collector has the biggest impact on your total cost:
Horizontal Trench (Slinky Collector)
Cost: £16,000 to £28,000 total installed
Horizontal systems use trenches dug at 1.2 to 2 metres deep across your garden. They're cheaper but need a large area of open ground — roughly 2 to 3 times the floor area of your home. Best suited to rural properties with big gardens or new-build sites where excavation is already happening.
Vertical Borehole
Cost: £24,000 to £45,000 total installed
Boreholes are drilled 80 to 200 metres deep and need very little surface space — just a few square metres for the drilling rig. The drilling itself typically costs £4,000 to £6,000 per 100-metre borehole, and most homes need 1 to 3 boreholes depending on heat demand. Thermal Earth operates its own specialist drilling rigs, which keeps costs down and gives us full control over quality.
Cost by Property Size
As a rough guide for a borehole system:
- 2-bed flat / small house (6-8 kW) — £18,000 to £25,000 (1 borehole)
- 3-bed semi / detached (10-12 kW) — £25,000 to £35,000 (2 boreholes)
- 4-5 bed detached (14-18 kW) — £32,000 to £45,000 (2-3 boreholes)
These figures are before the £7,500 BUS grant. Subtract £7,500 from each to get your out-of-pocket cost.
Running Costs — How Much Will You Save?
Ground source heat pumps are the most efficient type of heat pump, with COP ratings of 4.0 to 5.0. That means for every 1 kW of electricity used, you get 4 to 5 kW of heat.
In practice, this translates to:
- Typical annual heating cost: £600 to £1,200 (depending on home size and insulation)
- Savings vs gas boiler: 30% to 50% on heating bills
- Savings vs oil: 40% to 60% on heating bills
- Savings vs LPG: 50% to 70% on heating bills
Pair your heat pump with solar PV and you can reduce running costs even further by generating your own electricity.
The £7,500 Boiler Upgrade Scheme Grant
All ground source heat pumps are eligible for the £7,500 BUS grant. The scheme has been extended to 2030 under the Government's Warm Homes Plan, with increasing annual budgets. There's no income test — any homeowner in England or Wales can apply.
As an MCS certified installer, Thermal Earth handles the full BUS application. You don't need to apply separately.
Ground Source vs Air Source — Which is Better Value?
Air source heat pumps cost less upfront (£8,000 to £18,000 installed), but ground source heat pumps offer:
- Higher efficiency — COP 4.0-5.0 vs 2.8-3.5 for air source
- Lower running costs — 20% to 30% cheaper to run year-round
- Longer lifespan — 25+ years for the ground loop, 20+ for the heat pump (vs 15-20 for air source)
- Silent operation — no external fan unit
- Cooling capability — passive cooling in summer at virtually no extra cost
Over 20 to 25 years, a ground source system typically costs less in total than air source despite the higher upfront price. The right choice depends on your property, budget, and ground conditions.
How to Get an Accurate Quote
Every property is different, so the best way to get an accurate cost is a professional site survey. Thermal Earth offers free, no-obligation consultations including:
- Property heat loss assessment
- Ground condition evaluation
- System design recommendation
- Full cost breakdown including BUS grant
- Running cost estimate based on your property
Ready to find out what a ground source heat pump would cost for your home? Contact Thermal Earth for a free consultation, or call us to speak with one of our engineers.