How much does an air-to-air heat pump cost?

What an air-to-air heat pump costs to fit

An air-to-air heat pump costs from about £1,900 for one room to about £8,800 for a large home, on public estimates.

These are other bodies’ estimates, not our prices, and your quote may be higher or lower:

The estimates differ, and none says how many indoor units it assumes. Nesta doesn’t define its three sizes, and none gives a London figure, so treat them as a rough guide. Published air con prices for London.

Your own price comes from a survey of your home, not a price list. You get a written quote once we’ve surveyed it.

Many pages quote air source heat pump prices, which are for a different job. Those systems heat water for radiators, and Nesta’s estimate for them is £10,275 to £13,600 before any grant. Air-to-air and air-to-water compared.

Sources: the Energy Saving Trust (updated October 2026), the government (November 2025) and Nesta’s report on home heating options (February 2025).

What moves the price

The price moves mainly with the size of the job, because each extra room adds an indoor unit and more pipework. Six things make the difference.

Rooms to heat

More rooms mean a bigger job, so the price climbs with every room you heat. We work out the heat loss of each room at the survey, so each one gets the output it needs.

Indoor units

Each room or zone usually needs its own indoor unit, which is why Nesta says costs rise sharply in larger homes. An open-plan space can need fewer units.

A unit high on a wall is the usual kind. Hidden units cost more, because the job needs more building work.

The outdoor unit

The outdoor unit has to give enough heat on a cold day, not a mild one, so a bigger home needs a bigger unit.

One outdoor unit can feed up to five or six indoor units, depending on the make. Beyond that, a home needs a second outdoor unit.

Pipe runs

Pipe runs add materials and labour, so the distance between the units matters. Pipes usually run in a slim channel around the top of a room, and hiding them costs more.

A long run can affect the running costs too. The government’s review says it could be one reason real-world results fall short of lab figures.

Your home

Your home sets how long the job takes. Stairs and working height both count, and a scaffold adds to the price. A whole-home system often needs its own electrical circuit too.

The Energy Saving Trust adds that redecorating afterwards can be another cost. What affects any air con price.

Your old heating and hot water

Keeping your boiler is the simple case, as nothing has to come out. If the boiler goes, you’ll need another way to heat water, and we’ll look at the options at the survey.

On the government’s 2025 estimate, a 200-litre electric cylinder costs £600 to £1,500 to buy, before fitting. Taking out old radiators or pipes is a further cost, if you want that done.

Sources: Nesta’s report on home heating options (February 2025), the Energy Saving Trust, the government’s air-to-air review and the government’s heat pump checker.

Air-to-air heat pump running costs

Air-to-air heat pump running costs come to about 7.7p for each unit of heat, on MCS’s efficiency figure and today’s capped electricity price. That’s close to gas, and less than a third of the cost of direct electric heating.

A unit of heat here is a kWh, the measure on your energy bill. Each cost is the price divided by the efficiency, so 26.32p divided by 3.42 gives about 7.7p.

The 3.42 means 3.42 units of heat for each unit of electricity over a year, and MCS says it’s an assumption. The 2.8 is an older estimate in the government’s review, which adds that performance has improved since. The 84% is the figure the government assumes for gas boilers in homes.

Put side by side, a heat pump and gas come out close. The government’s review says heat pumps don’t generally bring big savings against gas boilers, because electricity costs more per unit. The real saving is against electric heating.

Treat these figures as a guide:

• The price cap: the sums use Ofgem’s cap for 1 October to 31 December 2026, by Direct Debit. The figure changes with each new cap, every three months, and your own rate may differ.
• Real use: MCS warns that real energy use can land 25% to 30% away from an estimate.
• VAT: the electricity price carries no VAT until July 2027, so it may rise after that.
• Standing charges: the sums leave these out.

If you’re on Economy 7, night rates are lower, so the gap against storage heaters is smaller. Replacing storage heaters.

Cooling adds a little in summer. One estimate in the government’s review put it at £20 to £90 a year for a mid-terraced London home. That’s at 2022 prices, with 2C of global warming.

Makers recommend a yearly service as well. What a service covers.

Work out what it would cost to run.

Sources: Ofgem’s price cap, MCS’s air-to-air standard, the government’s air-to-air review, its boiler assessment and Budget 2026.

How VAT and the grant fit in

VAT and the grant can both change what you pay, but the grant can’t be used yet.

VAT on an air-to-air heat pump

Firms registered for VAT charge 0% on fitting a fixed air source heat pump in a home until 31 March 2027. From 1 April 2027 they charge 5%.

The rate doesn’t depend on the grant. HMRC’s understanding is that most air conditioning units are air source heat pumps, though a portable unit doesn’t count. Doubtful cases turn on the facts.

VAT on air con and heat pumps.

Source: HMRC VAT Notice 708/6.

The £2,500 grant

The grant for air-to-air heat pumps is £2,500, and it has been in law since 28 April 2026. It can’t be used yet, because MCS says no installer is certified for these systems. We read that on MCS’s website on 1 November 2026.

MCS hasn’t given a date, so it’s best to plan on the full cost for now. You don’t need the grant to have a system fitted.

The grant also covers a narrow case: a system that replaces a home’s main heating, not a unit added to a room. It runs in England and Wales. Who the grant covers.

If you’re counting on it, timing matters, because Ofgem says applying after fitting carries extra risk. We’ll go through that at the visit.

Sources: the 2026 grant regulations, MCS on air-to-air systems and Ofgem’s guide for property owners.

When the cost makes most sense

The cost makes most sense in a smaller home, or where a heat pump replaces electric heating. These are the strongest cases:

• Electric heating: a storage heater or panel gives one unit of heat for each unit of electricity, and a heat pump gives about three.
• Flats and small homes: Nesta says these systems can be very affordable in small homes. A study for the government also modelled them as the lowest lifetime cost for every flat it looked at.
• Rooms that get hot in summer: one system heats in winter and cools in summer, so you aren’t paying for two.
• A room your radiators struggle with: you can keep the boiler and add one unit, which is a smaller job.

A large home costs more, because the indoor units add up quickly. We’ll say so at the survey if a smaller scheme would suit you better.

We fit these systems in all 32 London boroughs and the City of London. How we fit air-to-air heat pumps, and whether air con can heat your home.

In some cases planning or a lease affects where the outdoor unit goes. We’ll check that at the visit.

Sources: Nesta’s report on home heating options (February 2025), the government’s air-to-air review and the government’s heat pump checker.