UK price guide · Updated 26 Sep 2026
Bay Window Prices
Bay windows cost substantially more than flat casements because they use multiple framed sections and more installation work. In the current model, a standard replacement bay centres around £1,850–£2,850 depending mainly on section count.
Current price examples
These examples come from the same pricing model used by the calculator. They are market estimates rather than binding installer quotations.
Why bay windows cost more
A bay is effectively several windows joined into one projecting structure. The job involves more frame, more glass, bay poles or structural connections, longer cills and more fitting time.
The figures here are for replacing an existing bay. Creating a completely new bay or repairing major structural problems can cost considerably more and needs an installer survey.
Main price drivers
- 3, 4 or 5 framed sections
- Colour and foil finish
- Double or triple glazing
- Condition of the existing bay and surrounding structure
What “fitted” means here: supply, standard replacement installation and ordinary 20% VAT are included. Unusual access, scaffolding, structural repairs, planning/listed-building requirements and highly bespoke work can sit outside the standard estimate.
Related price guides
Compare closely related products before using the calculator for your exact specification.
Questions people ask
Short answers to the most useful questions around this price topic.
How much does a 3-section bay window cost?
Our current fitted-market centre is about £1,850, with a broad range around £1,369–£2,331.
Does this include building a new bay?
No. These are replacement-bay figures. New structural bay construction is a different project.
Can I price a coloured bay?
Yes. The calculator includes colour and glazing options for replacement bays.
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