Get a 2026 UK boiler replacement estimate in 30 seconds. Choose brand tier, boiler type and install scope for an instant low/mid/high figure — Worcester Bosch, Vaillant, Baxi and Ideal pricing with regional labour rates, supply-and-fit incl. VAT. No email required.
These figures power the calculator above — enter your own spec for a tailored estimate. For the full breakdown, read our complete cost guide.
Frequently Asked Questions
How much does a new boiler cost in 2026?
A like-for-like combi swap typically costs £1,600–£3,300 supply-and-fit in 2026 depending on brand tier. A premium boiler or a system change pushes it to £3,500–£5,200. The figure includes the boiler, flue, magnetic filter, labour, gas safety check, certification and VAT.
Why do Worcester quotes vary so much?
The difference is usually the model line. Worcester has several tiers (4000, 7000i, 8000 Style, 8000 Lifestyle): the 4000 sits in mid tier while the 8000 Lifestyle is premium with a 12-year warranty when installed by an accredited installer. Always check the model number, not just the brand.
What is the Boiler Upgrade Scheme (BUS)?
The BUS gives £7,500 toward replacing a fossil-fuel boiler with a heat pump — not a new gas boiler. Most homes still replace like-for-like because a gas boiler costs around a third of a heat pump upfront. If you are weighing a heat pump, compare on our cost guides first.
Should I get a magnetic filter fitted?
Yes. A magnetic filter (Magnaclean, Adey) captures metallic sludge before it reaches the boiler, extending its life and protecting the warranty. It is around £250 installed and is required for some Worcester and Vaillant warranties — most quality installers fit one as standard.
How long does a boiler installation take?
A like-for-like combi swap is usually one day. A system change such as regular → combi takes 2–3 days, and a full new install or major relocation 3–5 days. Every install includes a gas safety check, certification and Building Regulations notification.
How accurate is this boiler cost calculator?
It gives a guide range from typical 2026 rates for the boiler type, size and job you enter, not a fixed quote. The real price depends on whether you keep the same location, the condition of your pipework and flue, and any system upgrades needed. A Gas Safe engineer's survey confirms the spec, so the final quote may sit above or below the estimate.
What does the estimate include and exclude?
The figure covers the boiler, standard flue, fitting and commissioning. It usually excludes moving the boiler position, a full power flush, new radiators, a gas supply upgrade, a condensate pump, or upgrading a conversion from a system to combi boiler. Extra controls, a smart thermostat and making-good decoration are also priced separately once the engineer sees the property.
Why is my real boiler quote different from the calculator?
The tool uses average install rates, but a straight swap costs far less than a system conversion or a relocation that needs new pipe runs, gas and flue. Older systems often need a magnetic filter and flush that add cost. Boiler brand and warranty length change the price too, and London labour rates run higher than the national figure the calculator assumes.
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