How much does air conditioning installation cost in the UK?
Air conditioning is far less common in UK homes than in hotter climates, but demand has grown with warmer summers and more people working from home. Installation and servicing should be done by an F-Gas certified engineer. Here are typical costs for 2025–2026.
Typical air conditioning costs (2025–2026)
| Job type | Typical price range |
|---|---|
| AC service and gas top-up (minor) | £80 – £150 |
| Split unit installation (9,000 BTU / 2.5kW) | £800 – £1,400 incl. unit |
| Split unit installation (12,000 BTU) | £1,000 – £1,800 incl. unit |
| Split unit installation (18,000 BTU) | £1,400 – £2,400 incl. unit |
| Gas recharge (refrigerant only) | £100 – £200 |
| Fault diagnosis call-out | £70 – £140 |
| Control board / PCB replacement | £200 – £450 |
| Multi-split system (3 indoor units) | £2,500 – £4,500 incl. units |
| Commercial cassette unit installation | £2,000 – £4,000 incl. unit |
What affects the price?
- Unit size (BTU/kW). Larger or open-plan rooms need higher-capacity units. An undersized unit runs constantly without cooling adequately.
- Brand and efficiency rating. Inverter models cost more upfront but use significantly less electricity than fixed-speed units.
- Installation complexity. Long pipe runs, high wall positions, and multi-room (multi-split) installations all add to labour time.
- Refrigerant type. R32 is now the standard refrigerant for new domestic systems under UK F-Gas rules; older R410A systems are being phased down.
- Limited installer base. Because AC is less standard in UK homes than heating, there are fewer specialist installers than for boiler or plumbing work, which can affect both price and lead times.
Sizing guide
As a rough rule of thumb for UK conditions: allow approximately 100W of cooling per square metre of well-insulated living space. A 20m² bedroom typically needs a 9,000 BTU (2.5kW) unit; a 35m² open-plan area needs 12,000–18,000 BTU. Always have an installer do a proper load calculation rather than guessing — an oversized unit short-cycles and doesn't dehumidify properly.
Tips for getting a fair price
- Get a written, itemised quote separating the unit price, installation labour, and any materials (piping, brackets, cable).
- Confirm the engineer is F-Gas certified — handling refrigerants without the right certification is illegal in the UK. TruePro verifies F-Gas/REFCOM accreditation and shows a badge on the pro's quotes and profile once confirmed.
- Ask about inverter vs. fixed-speed for your use case — the electricity saving usually justifies the higher upfront cost within a few years of regular use.
- Don't pay the full amount upfront. TruePro's payment protection holds your payment securely until you've confirmed the work is complete.