The short answerPublished UK guides put air conditioning for one room at about £1,500 to £3,000 fitted, two rooms at about £3,200 to £4,500, three or four rooms at about £4,000 to £8,000, and ducted whole-house systems at £8,000 to £15,000 or more (Selectra, October 2026). Which? quotes about £1,900 for one room. London and the South East run 20 to 30 per cent higher.
Questions about your own home? Olly answers them himself.
How much air conditioning costs in the UK depends mostly on how many rooms you want to heat and cool, and how hard the install is. The figures below are published UK ranges from consumer and industry guides, with the source and date. They are not our prices. We give every customer a fixed written quote after a free survey, and these ranges help you judge whether a quote is in the right area.
How much does air conditioning cost in the UK in 2026?
Here are the latest published UK prices for fitted air conditioning that heats as well as cools (a split system, also called an air-to-air heat pump).
| System | Published fitted price | Source |
|---|---|---|
| Single split, one room | about £1,500 to £3,000 | Selectra, Oct 2026 |
| Single split, one room | about £1,900 | Which?, Jul 2026 |
| Multi-split, two rooms | about £3,200 to £4,500 | Selectra, Oct 2026 |
| Multi-split, three to four rooms | about £4,000 to £8,000 | Selectra, Oct 2026 |
| Multi-unit, three-bed semi | about £3,700 | Which?, Jul 2026 |
| Ducted, whole house | about £8,000 to £15,000+ | Selectra, Oct 2026 |
When the government announced grants for air-to-air heat pumps in November 2025, it gave about £4,500 as a typical cost to install in a flat or small house.
How much is air conditioning for one room?
For one room, most published prices fall between about £1,500 and £3,000 fitted. Selectra says labour makes up about £700 to £1,200 of that. The rest is the indoor unit, the outdoor unit, the pipework, the cable and the brackets.
A small bedroom or home office sits at the lower end. A large, glassy living room, or a room where the outdoor unit has to go high on a wall, sits at the top. For a sense of scale, recent Apex jobs include a 2.5kW wall unit for a bedroom and a 5kW unit for a living room in Bexley, and a 3.5kW unit for a garden room in South Darenth.
How much is air conditioning for a 3 bedroom house?
For two to four rooms, you are usually looking at a multi-split: one outdoor unit feeding several indoor units. Selectra lists two rooms at £3,200 to £4,500 and three to four rooms at £4,000 to £8,000. Which? quotes about £3,700 for a three-bedroom semi.
On a semi-detached or terraced house, planning rules allow only one outdoor unit without an application, so a multi-split is often the practical choice. On a detached house, two separate systems are allowed. Our guide to single split vs multi split explains the trade-offs.
Whole-house ducted systems hide everything in the loft or ceiling void and cost the most. See ducted air conditioning for how they work.
Does air conditioning cost more in Kent and London?
Yes, usually. Selectra says prices in London and the South East run 20 to 30 per cent above the rest of the country. If you live in Dartford, Bromley, Sevenoaks or south-east London, expect quotes in the upper half of the national ranges.
What affects the cost of air conditioning?
- The size of the unit. Worked out from the room’s heat gain. Bigger rooms, more glass and south-facing rooms need more capacity.
- The brand and range. Design-led units such as Daikin Emura, Mitsubishi Electric Zen or Panasonic Etherea cost more than standard white units.
- How many rooms. Each indoor unit adds cost. A multi-split saves outdoor units, but the outdoor unit is bigger.
- The pipe run. Most quotes include a standard run of a few metres. Longer runs, or pipes that have to go round the house, add materials and time.
- Where the outdoor unit goes. On the ground is simplest. High on a wall or on a flat roof may need brackets, access equipment or scaffold.
- The walls. Solid stone, thick period walls or reinforced concrete take longer to core-drill.
- The electrics. A dedicated circuit, an isolator and sometimes a consumer unit upgrade.
- Getting rid of the water. A gravity drain outside is simple. Where that isn’t possible, a small condensate pump is added.
- The finish. Plain trunking, colour-matched trunking, or pipes hidden in walls and ceilings.
- Controls. Wi-Fi, smart controllers and zoning such as Airzone.
- Ducted building work. Ducts, grilles, a plenum and making good ceilings.
- Paperwork. Listed-building consent, a planning application or a freeholder’s licence for a flat. Our planning permission guide explains when you need one.
How many kW of air conditioning do I need?
The right size comes from a heat-gain calculation for each room, not a rule of thumb. The building regulations guidance for homes (Approved Document L) says cooling should be based on a calculated heat gain and, in most cases, sized at no more than 120 per cent of the design cooling load.
That matters for cost in both directions. Too small and the unit runs flat out and still can’t cope. Too big and you pay more up front, and the unit switches on and off, which wastes energy. On our own jobs, bedrooms, home offices and garden rooms have mostly needed 2.5 to 3.5kW. Open-plan living spaces and lofts often need more.
Is it cheaper to fit air conditioning in winter?
Often, yes. Selectra notes that in the thick of summer installers are swamped, waits stretch to weeks and prices follow. Demand drops at the end of the season and better quotes appear. Booking between October and April also means the system is ready before the first heatwave, and you can use it to heat the room straight away.
Can I get a grant for air conditioning?
Possibly, but only in some cases. Since 28 April 2026, air-to-air heat pumps can get a £2,500 Boiler Upgrade Scheme grant in England and Wales. The system has to replace fossil-fuel heating, and it must be fitted by an MCS-certified installer. In April 2026 MCS said installers could not yet certify for air-to-air systems, so check the current position before you plan around it. One grant is allowed per property.
What will it cost to run and look after?
Buying it is half the picture. A modern unit used for cooling costs pennies an hour to run at the October to December 2026 price cap, and it heats far more cheaply than plug-in heaters. Our guide to air conditioning running costs shows the sums. Budget for a yearly service too, because manufacturers such as Daikin and Panasonic make annual maintenance a condition of their warranties. If you are still deciding whether to go ahead at all, read is air conditioning worth it in the UK?
Questions to ask on any quote
- Which exact model, and what size in kW, for each room?
- How did you work out the size?
- Where will the outdoor unit go, and has it been checked against the 37 dB(A) neighbour noise limit?
- Where will the pipes run, and how will they be finished?
- Is the electrical work included?
- What warranty applies, and what do I need to do to keep it?
- Is the company F-gas certified? Check the REFCOM, Quidos or Bureau Veritas register. Apex is on the REFCOM register as REF1017376.
Get a price for your own rooms
The fastest way to a real figure is a survey. Send Olly a photo of each room and the outside wall, or read how our air conditioning installation works, from sizing to the day of the fit.
Photos of the rooms and the outside walls get you a first idea, then a free survey.
