This guide separates heat-pump equipment, installation, grants and running costs. Use complete quotes for the purchase decision and the worked energy example below to understand the assumptions behind a running-cost estimate.
An air source heat pump typically costs £7,000–£13,500 installed in the UK. Air-to-water systems, the standard choice for radiator-based homes, range from £8,000 to £16,500 fully installed, with the top of that range for larger 4-bed homes. The UK government’s Boiler Upgrade Scheme (BUS) provides a £7,500 grant, reducing the net cost to a typical £4,500–£6,000 for eligible properties. Labour accounts for £3,500–£6,000 of the total; the remainder is hardware.
Ask your installer for a property-specific running-cost estimate, including hot water and any radiator or insulation work.
Choose an MCS-certified installer and confirm that the proposed system is eligible for the grant. Air-to-air systems heat air directly, while air-to-water systems serve a water-based heating circuit. Their installation scope and hot-water arrangements differ.
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- A £12,000 quote less a £7,500 grant leaves £4,500 to pay - check eligibility and include all cylinder, radiator, electrical and commissioning work in the quote.
- Our space-heating example costs £987 a year on the standard tariff - it assumes 12,000kWh of useful heat and seasonal efficiency of 3.2, excluding hot water and fixed charges.
- Cheap tariff windows do not apply to all your electricity - use the average rate across heat-pump consumption and include expensive periods in the comparison.
- Payback depends on the alternative you would actually buy - compare the extra upfront cost with annual savings, and do not assume future fuel prices.
How Much Does an Air Source Heat Pump Cost?
An air source heat pump costs £7,000-£13,500 installed in the UK, with an average of £12,000 for an air-to-water system before the £7,500 BUS grant.
The total cost of an air source heat pump depends on the type of system, your property size, and the complexity of the installation. An air-to-water ASHP (the most common type, which connects to radiators and underfloor heating) costs more than an air-to-air unit (which blows warm air directly into rooms).
| Cost Component | Air-to-Water | Air-to-Air |
|---|---|---|
| Supply only | £3,850 – £13,300 | £2,000 – £5,000 |
| Installation labour | £3,500 – £6,000 | £2,000 – £4,500 |
| Total installed | £8,000 – £16,500 | £4,000 – £9,500 |
| BUS grant | £7,500 | £2,500 |
| Net cost after grant | £500 – £9,000 | £1,500 – £7,000 |
These figures include VAT, which is currently 0% on heat pump installations (until March 2027). After this date, the reduced 5% rate returns, adding about 5% (roughly £400-£825 on the £8,000-£16,500 air-to-water range above).
Installation usually takes a few days for a typical home. Factors that push costs higher include: difficult access for the outdoor unit, upgrading radiators to work at lower flow temperatures, adding a hot water cylinder, or upgrading the electrical supply.
Air Source Heat Pump Costs by Property Size
A 1-2 bed home needs a 5-7 kW heat pump costing £7,000-£9,000 installed, while a 4-bed detached house requires 10-16 kW at £11,000-£16,500.
Heat pump sizing is based on your home’s heat loss, which correlates roughly with property size. An undersized unit won’t heat your home adequately; an oversized one wastes money upfront and cycles inefficiently. Our heat pump sizing guide walks through the full calculation. A qualified MCS installer will perform a heat loss calculation before recommending a system.
| Property Type | System Size | Installed Cost | After BUS Grant |
|---|---|---|---|
| 1-2 bed flat or terrace | 5-7 kW | £7,000 – £9,000 | £0 – £1,500 |
| 3-bed semi-detached | 7-9 kW | £9,000 – £12,000 | £1,500 – £4,500 |
| 4-bed detached | 10-16 kW | £11,000 – £16,500 | £3,500 – £9,000 |
The ranges above are indicative installer estimates. The Government’s own figures put the median Boiler Upgrade Scheme installation at about £12,500 before the grant (roughly £5,000 after it), so check any quote against that. These costs assume an air-to-water system with no major additional works. Add £500-£1,500 for a new hot water cylinder if you’re replacing a combi boiler (which doesn’t use one), and up to £9,000 if all radiators need upgrading, though our guide to heat pump radiators explains why most homes only need a subset changed.
Air-to-Water vs Air-to-Air Heat Pumps
Air-to-water heat pumps cost £8,000-£16,500 and provide heating plus hot water. Air-to-air units cost £4,000-£9,500 but only provide space heating, not hot water.
Most UK installations are air-to-water systems because they replace a gas boiler like-for-like: they connect to your existing radiators (or underfloor heating) and provide domestic hot water via a cylinder. Air-to-air systems are simpler and cheaper but only blow warm air into rooms – you still need a separate system for hot water.
| Feature | Air-to-Water | Air-to-Air |
|---|---|---|
| Installed cost | £8,000 – £16,500 | £4,000 – £9,500 |
| Hot water | Yes (via cylinder) | No |
| Works with radiators | Yes | No |
| Works with UFH | Yes (ideal pairing) | No |
| Cooling in summer | Some models | Yes (reversible) |
| BUS grant | £7,500 | £2,500 |
| Best for | Whole-house heating replacement | Single rooms, extensions, offices |
Air-to-water is the right choice for most homeowners replacing a gas or oil boiler. Air-to-air makes sense for supplementary heating in specific rooms, or in properties that already have separate hot water (e.g. an immersion heater or solar thermal).
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Air Source Heat Pump Running Costs
This space-heating example uses 12,000kWh of useful heat per year, a seasonal heat-pump efficiency of 3.2, and a gas boiler efficiency of 90%. It applies Ofgem’s average direct-debit unit rates for 1 October to 31 December 2026: electricity 26.32p/kWh and gas 7.97p/kWh. The electricity rate carries no VAT from 1 October 2026 to 31 March 2027; gas includes 5% VAT. It excludes hot water, standing charges, servicing and installation costs. Actual bills depend on your home and tariff.
| System or scenario | Energy used for the same heat | Annual space-heating cost |
|---|---|---|
| Heat pump, standard electricity rate | 3,750kWh electricity | £987 |
| Gas boiler, 90% efficient | 13,333kWh gas | £1,063 |
| Heat pump, illustrative 18p/kWh average paid rate | 3,750kWh electricity | £675 |
On the standard rate the heat pump costs about £76 a year less than this gas boiler. The lower-rate example saves about £388 a year against it, but 18p/kWh is an assumed average across all heat-pump consumption, not a supplier offer. A cheap overnight or midday window does not make every unit that price. Compare the whole tariff, including peak periods and household electricity use.
For the full calculation, including a separate hot-water example, see our heat pump running-cost guide. The source rates are on Ofgem’s unit-rate table.
BUS Grant and Other Heat Pump Funding
The Boiler Upgrade Scheme (BUS) provides £7,500 towards an air-to-water heat pump – rising to £9,000 for off-gas-grid homes replacing oil or LPG between 21 July 2026 and 31 March 2027 – or £2,500 for air-to-air units. The scheme now runs until 2030 and the grant is deducted from your installer’s quote.
The BUS grant is the main financial incentive for heat pump installations in England and Wales. It’s administered by Ofgem and must be applied for by an MCS-certified installer – you cannot claim it yourself. Here’s the full breakdown of available funding across the UK:
| Grant/Scheme | Amount | Eligibility | End Date |
|---|---|---|---|
| BUS – Air-to-Water ASHP | £7,500 | England & Wales, replacing fossil fuel | 2030 |
| BUS – Off-gas uplift (oil/LPG) | £9,000 | England & Wales, off-gas homes replacing oil or LPG (air-to-water or ground source) | 21 Jul 2026 – 31 Mar 2027 |
| BUS – Air-to-Air ASHP | £2,500 | England & Wales, replacing fossil fuel | 2030 |
| BUS – Biomass Boiler | £5,000 | Rural/off-gas grid only | 2030 |
| Home Energy Scotland | Up to £7,500 grant + £7,500 loan | Scottish homeowners | Ongoing |
| Warmer Homes Scotland | £10,000 or more of improvements (no cap stated) | Low-income Scottish households | Ongoing |
| Warm Homes Wales (Nest) | Fully funded (no published cap) | Low-income Welsh households | Ongoing |
| ECO4 | Up to 100% of cost | Low-income and vulnerable households in Great Britain; a contribution may apply | 31 December 2026 |
BUS Grant Eligibility Checklist
To qualify for the BUS grant, your installation must meet all of these criteria:
- You must own the property (landlords qualify for rented properties)
- The heat pump must replace an existing fossil fuel heating system (gas, oil, LPG, or electric)
- You no longer need a valid EPC to qualify – this requirement was removed for applications from 28 April 2026
- The installer must be MCS-certified
- Most new builds are excluded, but eligible self-builds and some finished new builds can qualify. Check the current property rules before ruling a home in or out.
The grant is applied as a discount on your installer’s invoice. You don’t receive cash – the installer claims it from Ofgem after the work is completed. Combined with the current 0% VAT rate (until March 2027), a typical installation costs roughly £4,500-£6,000 after the grant (the Government’s median installation cost is about £12,500 before it). For a city-level example, see our guide to air source heat pumps in Manchester.
Additional Installation Costs
Beyond the heat pump unit, budget £500-£9,000 for extras like radiator upgrades, a hot water cylinder, underfloor heating, or an electrical supply upgrade.
The headline installation cost covers the heat pump unit, outdoor mounting, pipework, and commissioning. But several common extras can add to the total, especially if your home hasn’t been adapted for low-temperature heating:
| Additional Work | Cost | When Needed |
|---|---|---|
| Radiator upgrades | £3,600 – £9,000 | If existing radiators are too small for low-temp flow (35-45°C) |
| Hot water cylinder | £500 – £1,500 | Replacing a combi boiler (which has no cylinder) |
| Underfloor heating (per floor) | £2,000 – £5,000 | Optional – ideal pairing for heat pumps (higher COP at lower temps) |
| Electrical supply upgrade | £500 – £1,000 | Older homes with undersized consumer units |
Radiator upgrades are the most common additional cost. Heat pumps run at lower flow temperatures (35-45°C) than gas boilers (60-80°C), which means you may need larger radiators to emit the same amount of heat. An MCS installer will calculate whether your existing radiators are adequate. In well-insulated homes with modern radiators, upgrades often aren’t needed.
Underfloor heating is the ideal companion for a heat pump. Because UFH runs at low flow temperatures, around 35°C, it suits a heat pump’s most efficient output range, so the combination typically delivers higher seasonal efficiency than radiators. If you’re renovating anyway, the lower flow temperature can reduce running costs, though the saving will not always cover the extra installation cost.
Heat Pump Brand Comparison
Samsung, Daikin, Vaillant and Hitachi all sell air-to-water heat pumps in the UK. Samsung, Daikin and Vaillant publish no UK retail prices, so the supply-only figures below are indicative installer-market estimates, running from about £3,000 for a Samsung to £10,000 for a Vaillant.
| Brand | Indicative Supply-Only Price | Strengths | Best For |
|---|---|---|---|
| Samsung EHS Mono | £3,000 – £7,000 | Competitive price, reliable, quiet operation | Budget-conscious homeowners |
| Hitachi Yutaki M | £4,000 – £7,000 | High efficiency, compact outdoor unit | Smaller properties, tight spaces |
| Daikin Altherma | £6,000 – £10,000 | Extensive installer network, proven track record, quiet | Larger homes, underfloor heating |
| Vaillant aroTHERM plus | £7,000 – £10,000 | Premium build quality, smart controls, high efficiency | Premium installations, integrating with solar PV |
MCS certification and BUS eligibility depend on the specific model and installation, so ask your installer to confirm both for the unit they quote. Manufacturer warranties often start at 2 years (Daikin and Vaillant both do) and can be extended to 5-7 years when an accredited installer registers the unit and annual servicing is kept up. Always check that your installer is an authorised dealer for the brand they recommend – this ensures warranty validity and access to manufacturer support.
Budget brands like Samsung offer the lowest upfront cost, but premium brands like Daikin and Vaillant may offer higher efficiency, which can lower running costs over the lifespan. The “best” brand depends on your property, budget, and whether you prioritise upfront savings or long-term efficiency.
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Heat Pump Payback Period
Calculate payback from the extra upfront cost of the heat pump compared with the alternative you would actually buy. Divide that difference by the annual saving after allowing for servicing and any changes to standing charges. If there is no annual saving, there is no running-cost payback.
Illustration: a £12,000 installation less a £7,500 grant leaves £4,500 to pay. If the alternative boiler quote is £3,500, the extra investment is £1,000. With the illustrative £388 annual saving above, simple payback is about 2.6 years. At the standard-rate saving of about £76 a year, the same £1,000 takes about 13 years to repay. These are assumptions, not typical quotes or a prediction.
If you are keeping a working boiler instead, the comparison changes because you are not avoiding a replacement purchase. Use your own quotes, annual heat demand and realistic seasonal efficiency. For oil or LPG, use recent delivered fuel prices and the existing system’s efficiency rather than a generic national saving.
Heat Pump Maintenance Costs
Annual heat pump servicing costs £150-£300, with a typical lifespan of 20 years. Repairs average £500 but range from £150 for minor fixes to £2,000 for compressor replacement.
Heat pumps have no combustion, flue or gas valve, but that does not make them cheaper to service: an annual heat pump service typically costs more than a gas boiler service (British Gas lists £109 a year for a boiler). An annual service is recommended to maintain efficiency and warranty validity.
| Maintenance Item | Cost | Frequency |
|---|---|---|
| Annual service | £150 – £300 | Yearly |
| Typical repair | £500 | As needed |
| Compressor replacement | £1,000 – £2,000 | Rare (check how long your warranty runs) |
| Refrigerant recharge | £150 – £400 | If pressure drops (leak repair separate) |
Over a 20-year lifespan, servicing alone costs £3,000-£6,000 at the £150-£300 annual rate. The key difference is that heat pumps don’t require a Gas Safe engineer, and there’s no annual gas safety certificate to arrange. Some manufacturers offer extended warranties (up to 7 years in the cases we have checked, such as Daikin, Vaillant and NIBE) if an accredited installer registers the unit and annual servicing is kept up.
Is an Air Source Heat Pump Worth It?
An air source heat pump is worth it if you’re replacing an old, inefficient boiler or off-gas heating (oil, LPG, electric). It’s harder to justify against a working new gas boiler purely on running costs.
The decision depends on your current heating system, home insulation, and time horizon.
Strong case for a heat pump:
- Your boiler is 15+ years old and due for replacement anyway
- You’re on oil, LPG, or electric heating (immediate running cost savings)
- Your home is reasonably well insulated
- You have underfloor heating or are willing to upgrade radiators
- You plan to stay in the property for 10+ years
- You want to reduce your carbon footprint (lower emissions than gas on the current UK grid, and improving as the grid decarbonises)
Weaker case for a heat pump:
- You have a new, efficient gas boiler that’s working well
- Your home has poor insulation and you can’t or won’t upgrade it
- You plan to move within the next 5 years
- You’re only motivated by running cost savings (the case is marginal vs mains gas at today’s prices)
Future energy prices are uncertain. Base the decision on current quotes and a range of running-cost scenarios, rather than assuming electricity prices or property values will move in your favour.
How to Get the Best Price on a Heat Pump
Get at least three quotes from MCS-certified installers, confirm BUS grant eligibility before signing, and check that the quote includes all ancillary costs like cylinder and radiator upgrades.
Heat pump prices vary significantly between installers, so quotes for the same property can differ by thousands of pounds. Follow these steps to ensure you get the best value:
- Get 3+ quotes from MCS-certified installers. Only MCS installers can apply for the BUS grant on your behalf. Check the MCS Installer Lookup tool to find certified companies in your area.
- Ensure the quote includes a heat loss survey. A reputable installer won’t recommend a system size without measuring your home’s actual heat loss. Be wary of quotes based on floor area alone.
- Check what’s included. Does the price cover the BUS grant application, cylinder, controls, radiator upgrades (if needed), electrical work, and commissioning? Get an all-in price.
- Ask about the brand and warranty. Manufacturer warranties often start at 2 years and can be extended to 5-7 years through an accredited installer with annual servicing. Check the installer is an authorised dealer for the brand.
- Time your installation. Spring and summer are the best times to install (lower demand, faster scheduling, and you’re not without heating during installation).
Use our free quote comparison tool to receive up to 3 tailored quotes from MCS-certified installers in your area. There’s no obligation and it takes less than 2 minutes.
