In July 2026, two air conditioning quotes for the same UK postcode can differ by thousands of pounds without either being fraudulent. The gap usually comes from different room loads, outdoor positions, pipe and drain routes, electrical allowances, working hours, consent risk and how much contingency the installer has built in. Buyers who compare headline totals before comparing assumptions often pick the wrong quote. The useful skill is to force every proposal onto the same scope, then judge price.
The quote is a risk price, not a catalogue sticker
An installer is pricing uncertainty as much as equipment. A short rear-wall penetration with clear outdoor space is a different job from a flat with lease consent pending, a long condensate pump run and evening-only access. Labour, parking, scaffold and the chance of a freeholder objection all sit inside the number even when the indoor unit looks identical.
That is why published budgeting bands remain useful for orientation and weak as a substitute for a survey. Ranges on this site are planning aids. They compress a wide distribution of site outcomes into a single interval.
Where the money actually moves
Capacity selection should follow heat gain, not floor area folklore. A west-facing glazed extension can need more cooling than a larger shaded bedroom. If one quote sizes from area rules and another from glazing, occupancy and roof exposure, the equipment schedules will diverge before labour is even considered.
Outdoor siting is the second major fork. Rear gardens, lightwells, balconies and roofs create different acoustic, airflow and access costs. London and dense Greater Manchester streets often add parking, congestion and restricted hours. Those line items rarely appear as a clean 'London premium' label; they appear as longer days and more plant hire.
- Ask for design conditions and room-by-room assumptions.
- Make outdoor positions explicit in writing.
- Separate equipment, labour, access, electrics and consent work.
- Treat verbal ballparks as provisional until surveyed.
Consent friction is priced even when it is not itemised
Leasehold and landlord processes do not only delay projects. They change the installer's risk. A company that has lost days waiting for managing-agent replies learns to price that uncertainty, or to exclude consent support entirely. A cheaper quote that assumes consent will be 'sorted by the client' is not cheaper if the programme stalls.
Planning ambiguity has a similar effect. Cooling-only plant, conservation settings and prominent elevations create different paperwork paths from a discreet reversible unit on an unrestricted house. Two quotes may both be 'valid' while answering different permission questions.
How to make quotes comparable
Send every installer the same brief: rooms to cool, preferred outdoor options, photos, lease constraints, target programme and whether heating is required. Ask each proposal to state make, model, duty, pipe length allowance, condensate method, electrical inclusions, access equipment, VAT and exclusions.
Then compare residual risk. The lowest number with the longest exclusion list is often the most expensive once variations arrive. For continuous IT cooling, insist on heat-load basis and failure behaviour rather than borrowing a comfort-cooling template.
Frequently asked questions
Does a higher quote always mean better quality?
No. It may reflect harder access, quieter equipment, fuller electrical scope or simply more contingency. Read the assumptions before judging value.
Should I average several quotes?
Averaging hides disagreement. Align the scopes first. If one quote is an outlier after alignment, ask why rather than blending it away.
Are online price calculators enough?
They help frame a budget and questions. They are not a substitute for a surveyed written proposal.
Core buying guides
Start with these high-intent guides, then dig into the rest of the library.
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.