How much does a heat pump cost to install?

A typical air source heat pump (ASHP) costs £8,000–£14,000 installed in the UK, while ground source heat pumps (GSHP) range from £15,000–£35,000 depending on property size and ground conditions. These figures include the unit, labour, electrical work and commissioning. The £7,500 BUS grant can significantly reduce the net cost.

What is the BUS grant?

The Boiler Upgrade Scheme (BUS) provides a £7,500 grant towards heat pump installation in existing homes in England and Wales. You must use an MCS-certified installer, and the property must have a valid EPC with no outstanding loft or cavity wall insulation recommendations. The grant is applied at the point of installation — you do not need to pay the full cost upfront.

Is a heat pump cheaper to run than gas?

It depends on the coefficient of performance (COP). At a seasonal COP of 3.5 or above, an air source heat pump produces 3.5 kWh of heat for every 1 kWh of electricity used. At current UK energy prices (electricity ~27.7p/kWh, gas ~5.9p/kWh), a heat pump with COP 3.5 costs roughly the same per kWh of heat as a 90% efficient gas boiler. Higher COPs or time-of-use tariffs tip the balance in favour of the heat pump.

Do I need new radiators for a heat pump?

Often yes. Heat pumps operate most efficiently at lower flow temperatures (around 45°C versus 65°C for a gas boiler). At lower temperatures you need larger radiator surface area to deliver the same heat output. A professional heat loss survey will identify which rooms, if any, need larger radiators. In well-insulated homes the existing radiators may be adequate.

ASHP vs GSHP — which is better?

Air source heat pumps are far more common (over 90% of UK installations) because they are cheaper to install and require no ground works. Ground source heat pumps achieve higher COPs (typically 4.0 vs 3.5) and are quieter in operation, but cost roughly double to install due to borehole drilling or trench excavation. GSHP is best suited to larger properties with available land, while ASHP works well for most homes.

Heat Pump Cost Calculator — Installation, Grants and Savings

How We Calculate This

Installation Costs

Total installation cost is estimated based on your property size and heat pump type. It includes the heat pump unit, labour and installation, electrical work, and optional extras like radiator upgrades and hot water cylinder. Larger properties need higher-capacity units with more complex installation, so costs scale accordingly.

ASHP typically costs £8,000–£14,000 installed
GSHP typically costs £15,000–£29,000 installed (includes ground works)

BUS Grant

The Boiler Upgrade Scheme (BUS) provides a £7,500 grant towards heat pump installation in existing homes in England and Wales. The grant is deducted from the total cost at the point of installation — you do not pay the full amount upfront.

Must use an MCS-certified installer
Property must have a valid EPC
No outstanding loft or cavity wall insulation recommendations on EPC
Applies to both ASHP and GSHP installations

Running Cost Comparison

The coefficient of performance (COP) measures how efficiently the heat pump converts electricity into heat. A COP of 3.5 means 1 kWh of electricity produces 3.5 kWh of heat. Annual running cost = heat demand ÷ COP × electricity price. Your current system cost = heat demand ÷ boiler efficiency × fuel price.

ASHP seasonal COP: typically 3.0–4.0 (default 3.5)
GSHP seasonal COP: typically 3.5–5.0 (default 4.0)
Payback period = net cost after grant ÷ annual saving

Why Radiators Matter

Heat pumps work most efficiently at lower flow temperatures (around 45°C vs 65°C for a gas boiler). At lower temperatures, radiators need a larger surface area to deliver the same heat output. A professional heat loss survey will identify which rooms need upgraded radiators. In well-insulated homes, existing radiators may be adequate.

Carbon Savings

CO₂ savings are calculated using BEIS emission factors. The UK electricity grid produces 0.136 kgCO₂/kWh (2026 average), which is already lower than gas (0.183), oil (0.245), and LPG (0.214). Because the heat pump multiplies each kWh of electricity by the COP, the effective emissions per kWh of heat are even lower. As the grid continues to decarbonise, heat pump carbon savings will increase further.