A single-split system with one indoor unit and one outdoor unit may cost roughly £1,500 to £3,000 including VAT for a straightforward UK domestic installation in July 2026. London and technically difficult sites may be closer to £1,800 to £3,500 or more. Capacity, equipment quality, pipe length, electrical work, condensate disposal and access are major variables, so the useful comparison is a complete written scope rather than the unit price alone.
What a single-split price should cover
A complete quote normally identifies the indoor and outdoor models, standard pipework allowance, insulation, cable, trunking, brackets or feet, condensate route, electrical connection, pressure testing, evacuation and commissioning. It should also state whether VAT and disposal are included.
Some low headline prices assume a very short back-to-back route and an existing suitable power supply. Ask for the cost of extra pipework, a condensate pump, access equipment and making good before accepting.
Equipment and design choices
Wall-mounted units are common, but floor, cassette and concealed ducted indoor units can change both equipment and building-work costs. Wi-Fi controls, enhanced filtration and very low sound modes may add value for some households but should not replace correct sizing.
A load calculation should account for solar gain, fabric, ventilation, occupancy and internal gains. Selecting by a simple watts-per-square-metre rule can be misleading, especially for loft rooms and heavily glazed spaces.
Installation and certification
Fixed split systems generally require work on fluorinated refrigerant circuits. The company carrying out installation or maintenance on relevant stationary equipment must hold the required company certification, and individuals doing regulated tasks must have appropriate qualifications.
Ask for the installer's company certificate details and commissioning records. Certification demonstrates the required competence framework for F-gas work, but it is not a general guarantee of price, workmanship in every trade or customer service.
Whole-life cost
Purchase price is only one part of ownership. Electricity use, filter cleaning, periodic servicing and eventual repair all matter. Reversible models can also provide heating, which changes how their annual energy use should be considered.
Compare seasonal efficiency information for like-for-like capacities. Real consumption will still depend on controls, weather, set points and the building, so a predicted annual cost should always list its assumptions.
Frequently asked questions
What is the difference between a split and a portable air conditioner?
A split has separate indoor and outdoor components joined by refrigerant pipework. A portable unit keeps most components indoors and exhausts warm air through a hose, which is easier to deploy but often noisier and less efficient.
How long does a simple split installation take?
Many straightforward jobs can be completed within a day, but access, pipe routes, electrical work and testing may extend the programme. The quote should state the expected duration.
Can I install a pre-charged split system myself?
Do not assume that pre-charged equipment removes legal requirements. Work involving regulated F-gases must be carried out by appropriately qualified personnel and, where applicable, a certified company.
Core buying guides
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Related guides
Sources and further reading
How this guide was prepared
This guide was written by the Local AC Installers Editorial Team. We compare official guidance, legislation and established consumer information, separate general information from project-specific advice, and show publication dates and sources. We do not accept installer accreditation claims at face value.