Cost guides › Replacement windows
United Kingdom
How much do replacement windows cost?
Replacing 6 average-sized windows with new uPVC double glazing typically costs £3,550 including VAT, with most quotes between £2,800 and £4,650. The price includes taking out the old frames, fitting and sealing the new windows, new internal window boards and making good the plaster and reveals. Standard white uPVC comes in around £3,200; timber-aluminium composite windows are about £14,000.
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mid-range, typicalCost by region
| Location | Basic | Mid-range | Premium |
|---|---|---|---|
| London | £3,350 | £3,700 | £14,500 |
| Scotland | £3,250 | £3,600 | £14,100 |
| East | £3,200 | £3,550 | £13,900 |
| North West | £3,200 | £3,550 | £13,900 |
| South East | £3,200 | £3,550 | £14,000 |
| South West | £3,200 | £3,550 | £13,800 |
| West Midlands | £3,200 | £3,550 | £13,800 |
| East Midlands | £3,150 | £3,500 | £13,800 |
| North East | £3,150 | £3,500 | £13,800 |
| Wales | £3,150 | £3,500 | £13,800 |
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| Yorkshire and The Humber | £3,150 | £3,500 | £13,700 |
What's included
Mid-range
- Removal of the old window frames, taken away for disposal
- New two-sash uPVC windows of about 1.2 x 1.4 m with a woodgrain foil finish
- Double glazing with a whole-window U-value of 1.3 W/m²K or better
- Fitting with the joint between frame and wall sealed inside, in the middle and outside
- Old internal window boards removed and new polished stone boards fitted
- Plaster made good around each new frame
- Internal reveals repainted
What affects the cost
Size and style of window
Our estimate assumes average windows of about 1.7 m². Large picture windows, bays, sash-style uPVC and arched heads cost considerably more per window, and French or patio doors are priced separately.
Frame material and finish
White uPVC is the cheapest option. Coloured or woodgrain foils add to the price, and aluminium or timber-aluminium composite frames cost more again but give slimmer sightlines and a longer life.
Glazing specification
Standard double glazing is what most homes get. Triple glazing, acoustic glass for busy roads and obscure or toughened glass in bathrooms and near doors all add to the unit price.
Access to upper floors
Most windows can be fitted from inside with ladders. Tall houses, windows over conservatories or flats above the first floor may need scaffolding or a tower, which is not included here.
Condition of the openings
Rotten timber lintels, crumbling reveals or cracked external sills are found when the old frames come out. Replacing external sills and repairing brickwork is extra.
Listed buildings and conservation areas
In a conservation area or a listed building, uPVC may not be accepted and you may need consent for replacement windows. Timber or slimline alternatives cost more.
How to save
- Replace all the windows in one job; the fitting team's day rate and set-up are spread over more units.
- Stay with white uPVC and standard casement styles, which are the cheapest to make.
- Keep your existing window boards if they are in good condition.
- Get at least three quotes on the same specification, including the U-value and glass type, so you compare like with like.
Grants, tax and rules
Building regulations
Replacement windows must meet building regulations. A FENSA or CERTASS registered installer self-certifies the work, and you should receive the certificate; keep it, as buyers' solicitors ask for it.
VAT
Our figures include 20% VAT. Replacement windows are not on the list of energy-saving materials that qualify for 0% VAT.
Frequently asked questions
How much do uPVC windows cost in the UK?
For 6 average-sized uPVC windows fully fitted with new window boards and making good, expect around £3,550 including VAT. White uPVC without extras is closer to £3,200. Bay windows, large openings and upper-floor access increase the price.
Do I need a FENSA certificate for new windows?
You need proof that the windows meet building regulations. A FENSA or CERTASS registered installer self-certifies the work; otherwise you must apply to building control yourself. The certificate is normally requested when you sell the house.
How long does it take to replace windows?
A fitting team usually replaces several windows a day, so a typical house takes one to three days. Allow a few weeks beforehand for survey and manufacture, as windows are made to measure.
Is triple glazing worth it in the UK?
Triple glazing cuts heat loss a little further and helps with noise, but costs more and the frames are heavier. For most homes, good double glazing with a low U-value is the better value; triple glazing makes more sense on north-facing or very exposed walls.
Can I get a grant for new windows?
Replacement windows are not covered by the Boiler Upgrade Scheme, and they do not get the 0% VAT rate for energy-saving materials. The Warm Homes Plan includes grants for low-income households and low- or zero-interest loans being phased in, so check whether your household and the work qualify.
How this estimate is calculated
Work hours: 10 · Labour: £1,018 · Materials: £1,961
Sources: ONS Annual Survey of Hours and Earnings, tables 14 and 15; Regione Toscana, Prezzario dei Lavori 2026 (CC BY 4.0); ECB exchange rates.