Air Source Heat Pump Costs UK (2025 Guide)

Air source heat pumps have moved from niche to mainstream – but one of the first questions people ask is: “How much does a heat pump actually cost?”

Headline numbers vary wildly, and it’s not always clear what’s included. This guide breaks down typical air source heat pump costs in the UK for 2025, how grants can reduce the bill, and how they compare with replacing a gas boiler.

Typical installation cost ranges by property type
What’s usually included in a quote – and what isn’t
How grants like the Boiler Upgrade Scheme change the maths
When a heat pump makes sense vs sticking with a boiler

For a side‑by‑side comparison, see Boiler vs Heat Pump: Costs, Savings & Which Is Right for You. For boiler‑only pricing, read New Boiler Cost UK (2025): Complete Price Guide.

1. Typical air source heat pump costs in 2025

Every home is different, but broad pre‑grant ranges for a full air source heat pump installation (unit + controls + typical system changes) are:

Small flat / well‑insulated home: around £7,000–£10,000+
Average 3‑bed semi: around £9,000–£13,000+
Larger or more complex homes: £12,000–£18,000+ or more, especially with extensive radiator or cylinder upgrades

These figures can fall significantly once you factor in grants (see below). The only way to get an accurate price is via a heat‑loss‑based design and quote for your specific property.

2. What’s included in a typical heat pump quote?

Behind a single number, you’re usually paying for:

Heat pump unit and outdoor fan (plus any indoor module).
Hot water cylinder (for most systems) and associated components.
System design and heat‑loss calculations to size the pump and emitters.
New or upgraded controls (thermostats, programmers, smart controls).
Radiator upgrades or underfloor circuits where needed.
Installation labour, commissioning and certification.

Good quotes also account for:

Electrical work (dedicated supply, consumer‑unit checks).
Mounting, slab or wall brackets for the outdoor unit.
Any planning or consent requirements in sensitive areas.

If a quote looks unusually cheap, check what’s missing (e.g. no radiator upgrades, minimal design work, unclear guarantees).

3. What affects heat pump cost the most?

Key factors that move your quote up or down:

Property size and heat demand

Larger homes with higher heat loss need:

Bigger or more powerful heat pump units.
More emitters (radiators/underfloor circuits).
More time on design and installation.

Existing heating system

Costs are typically lower when:

The existing system already has reasonably sized radiators.
Pipework is in good condition and well‑laid out.
You have a suitable hot water cylinder that can be reused.

They’re higher when:

You’re converting from direct electric or storage heaters.
Pipework is undersized or cluttered and needs significant rework.

Fabric and efficiency

Well‑insulated homes (good loft, walls and windows) often:

Need smaller heat pumps.
Achieve better seasonal efficiency (SCOP).

Leaky homes either demand more fabric work upfront or risk higher running costs and lower comfort if heat pump performance is compromised.

Brand, installer and warranty

Premium brands, longer warranty periods and reputable installers cost more but can reduce long‑term risk.
Cheaper quotes may mean shorter warranties or less aftercare.

4. Grants and funding for air source heat pumps

The Boiler Upgrade Scheme (BUS) is a major driver of heat pump adoption:

Offers a grant worth several thousand pounds off eligible installations (amounts and rules may change, so always check current guidance).
Typically applies to owner‑occupied homes in England and Wales with a valid EPC (sometimes requiring insulation measures first).

Other support may be available through:

Local authority schemes targeting cold homes and decarbonisation.
Broader home energy grants that include fabric and heating upgrades – see Home Energy Grants UK 2025: Complete Guide to Funding (/insights/home-energy-grants-uk).

If you’re on a low income or in a very inefficient home, schemes like ECO4 may fund insulation and, in some cases, heating changes – see Boiler Grants UK 2025 for the boiler‑side of this landscape.

5. Running costs: when can a heat pump be cheaper?

A well‑designed heat pump in a suitable home can:

Use significantly less energy (in kWh of heat) than a boiler for the same comfort level.
Take advantage of time‑of‑use tariffs, smart controls and self‑generated solar electricity (if you have PV).

However, actual running costs depend on:

The performance of the heat pump (SCOP).
Your electricity tariff versus gas prices.
How you use heating and hot water (temperature, hours, zoning).

We explore cost trade‑offs in Boiler vs Heat Pump: Costs, Savings & Which Is Right for You.

6. EPC and carbon benefits of heat pumps

From an EPC perspective:

Heat pumps are usually treated very favourably because they deliver multiple units of heat per unit of electricity.
Switching from a gas boiler to a well‑specified heat pump can often boost your EPC score, especially when combined with good insulation.

Heat pumps also:

Cut direct emissions by removing on‑site gas or oil combustion.
Benefit over time from a decarbonising electricity grid.

For broader EPC strategies, see 27 Ways to Improve Your EPC Rating and the band‑specific guides How to Improve EPC from E to D and How to Improve EPC from D to C.

7. When an air source heat pump makes sense

It’s most promising when:

Your home is well insulated, or you’re committed to improving the fabric.
You have (or are willing to install) larger radiators or underfloor heating.
You’re planning to stay long enough to benefit from lower carbon and potentially competitive running costs.

It can be more challenging when:

The property is very draughty or hard to insulate.
You need high flow temperatures for an older radiator system and can’t upgrade emitters.

In these cases, a staged plan (fabric upgrades first, then heat pump) or a new boiler may be more realistic in the short term.

8. Landlords and heat pumps

For landlords, heat pumps are increasingly relevant to:

Meeting or exceeding minimum EPC standards.
Making rentals more attractive to tenants who care about bills and sustainability.

However, they demand careful planning:

Upfront costs are higher than boiler swaps.
Coordination with tenants is essential to minimise disruption.

Use EPC Rules for Landlords in 2025–2030 and EPC Exemptions for Landlords to see where heat pumps fit your long‑term strategy.

9. Next steps

Check your current heating, EPC rating and recommendations via our EPC checker.
Improve insulation and draught‑proofing first if needed – heat pumps perform best in efficient homes.
Read Boiler vs Heat Pump: Costs, Savings & Which Is Right for You alongside New Boiler Cost UK (2025): Complete Price Guide.
Explore grant eligibility via the Boiler Upgrade Scheme and local programmes, using Home Energy Grants UK 2025 (/insights/home-energy-grants-uk) as a companion.

That way, when you decide whether to install an air source heat pump, it’s based on clear costings, realistic performance expectations and a joined‑up EPC improvement plan.