How Much Does a Heat Pump Cost in the UK?

Average Supply and Install Costs by Heat Pump Type

Air-Source Heat Pumps

An air-source heat pump (ASHP) takes heat from the outside air and upgrades it for your central heating and hot water. It's the most common type installed in UK homes. A full system typically includes the outdoor unit, an indoor unit or hydraulic module, a hot water cylinder, controls, and any radiator or emitter upgrades. For an average three- or four-bedroom house, expect to pay roughly £10,000–£18,000 for supply and installation before any grants. Smaller properties might come in at £8,000–£12,000; larger or more complex homes can exceed £20,000. The range reflects different equipment quality, property size, and whether you need significant radiator or underfloor heating work.

Ground-Source Heat Pumps

Ground-source heat pumps (GSHPs) use pipes buried in the ground (horizontal trenches or vertical boreholes) to extract heat. They are generally more efficient than air-source in cold weather but need more space or drilling, so installation is more involved and costly. Supply and install for a typical home often runs from £18,000–£35,000 or more before grants. Borehole systems are usually at the upper end because of drilling and groundworks. Ground-source is most common in new builds or properties with plenty of land; many existing UK homes suit an air-source pump and cylinder instead.

Running Cost Comparison vs Gas Boiler

Whether a heat pump saves you money on bills depends on your electricity and gas tariffs and how well your home is insulated. Heat pumps use electricity but deliver several units of heat for each unit of electricity (a typical COP might be 2.5–3.5). Gas boilers are efficient but burn gas, so when gas is cheap and electricity is expensive, a boiler can still be cheaper to run. When the gap between electricity and gas prices narrows—or you use a competitive or off-peak electricity tariff—a heat pump can match or beat gas running costs, especially in well-insulated homes with low flow temperatures.

As a rough illustration: at 28p/kWh electricity and 7p/kWh gas, a heat pump with a COP of 3 might cost a similar amount per kWh of heat as a 90% efficient boiler. Real bills depend on your usage, insulation, and exact tariffs. Getting a heat loss survey and installer advice will give you a clearer picture. The key point is that running costs are no longer automatically higher with a heat pump, and they improve as the grid gets greener and heat pump tariffs become more common.

The £7,500 BUS Grant and How to Apply

The Boiler Upgrade Scheme (BUS) in England and Wales offers a grant of up to £7,500 towards the cost of an eligible air-source or ground-source heat pump installation. The grant is paid to your installer, who deducts it from the price they quote you, so you pay the balance. For example, a system quoted at £14,000 might cost you £6,500 after the grant—bringing it much closer to the cost of a premium gas boiler and cylinder.

How to apply: You don't apply for the grant yourself. You choose an MCS-certified installer who is registered for BUS. They will carry out the heat loss survey, design the system, and apply for the grant on your behalf. You must own the property (or have the owner's consent), be replacing existing fossil fuel heating (e.g. gas or oil boiler), and meet the scheme's eligibility rules. Funding is limited and allocated on a first-come, first-served basis, so confirm with your installer that they have applied and that the grant is reserved before you commit. Scotland and Northern Ireland run separate grant schemes—check the latest guidance for your region.

Factors That Affect Your Heat Pump Cost

Property Size and Heat Loss

Larger homes with higher heat loss need a larger heat pump and more emitters, which increases the equipment and labour cost. A small, well-insulated flat might need a 5 kW unit and minimal changes; a large detached house might need 12–15 kW and more radiator or underfloor upgrades. A proper heat loss survey (MCS style) will determine the right size and help you avoid over- or under-spending.

Insulation and Fabric

Improving insulation and airtightness before or alongside a heat pump install can reduce the size of the unit you need and the flow temperature it must run at. That often means lower upfront cost and better running costs. Some installers and schemes encourage a "fabric first" approach: loft insulation, cavity or solid wall insulation, and better windows can make the heat pump install simpler and more effective.

Radiator and Emitter Upgrades

Heat pumps run most efficiently at lower flow temperatures (e.g. 35–45 °C). Many existing UK radiators were sized for boiler flow at 60–70 °C, so they may need to be replaced or upgraded (e.g. double or triple panels, or larger sizes) to deliver enough heat at lower temperatures. The cost of radiator upgrades varies by room count and existing layout; your installer should include this in the quote. Underfloor heating is an alternative that works very well with heat pumps but adds to the project cost if retrofitted.

Next Steps for UK Homeowners

Use the cost ranges and grant information above to set your expectations, then get at least three quotes from MCS-certified installers. Ask each for a written quote that includes the heat pump, cylinder, controls, and any radiator or other upgrades, and confirm whether the £7,500 BUS grant is included in the price they give you. Run your property details through our heat pump size calculator to get a rough kW range before you meet installers—it will help you judge whether their recommendations are in the right ballpark. A well-sized heat pump, installed to MCS standards, can provide reliable heating and hot water for years while cutting your carbon footprint and potentially your running costs.