How much does a new boiler cost in the UK?
Last updated 13 August 2026 · 7 min read · Reviewed by the GotAPal editorial team
A new boiler is one of those big, unavoidable spends that tends to arrive at the worst possible moment. The good news is that prices are fairly predictable once you know your boiler type and what the install involves. Here is what a new boiler typically costs across the UK in 2026, fully fitted.
The short version
- A straight combi swap is usually £1,800 to £3,500 fitted.
- A system boiler runs roughly £2,000 to £4,000 installed.
- Moving the boiler, a new flue or a power flush all add cost.
- Only a Gas Safe registered engineer can legally fit a gas boiler.
- Get a fixed written price for like-for-like scope, and check the warranty length.
Boiler types and what they cost
Which boiler suits your home depends on how many bathrooms you have and your hot water demand. The three common types are:
- Combi boiler: heats water on demand with no tank, ideal for smaller homes and flats. A like-for-like swap is usually £1,800 to £3,500 fitted.
- System boiler: works with a hot water cylinder, better for homes with two or more bathrooms. Expect roughly £2,000 to £4,000 installed.
- Conventional (regular or heat-only) boiler: uses a cylinder and a cold water tank in the loft, common in older houses. Installed prices are similar to system boilers, and more if the whole setup is replaced.
Typical installed prices
| Job | Typical cost |
|---|---|
| Combi swap (like-for-like) | £1,800 to £3,500 |
| System boiler (installed) | £2,000 to £4,000 |
| Conventional boiler (installed) | £2,000 to £4,000 |
| Full swap with new flue and controls | £3,000 to £4,500 |
| Convert combi to system boiler | £3,500 to £6,000 |
| Back boiler removal and replacement | £3,500 to £6,000 |
| Change fuel type (new gas supply) | £4,000 plus |
What mhanges the price
- Moving the boiler. Relocating it to a new wall means new pipework and a new flue route, which adds time and cost.
- A new flue. Longer or awkward flue runs cost more than a simple through-the-wall exit.
- Filter and controls. A magnetic system filter, a smart thermostat and new TRVs (thermostatic radiator valves) are often added and are well worth having.
- Power flush. If the system is sludgy, a power flush of roughly £300 to £600 protects the new boiler.
- Conversion work. Converting a combi to a system boiler, or removing an old back boiler, is a bigger job than a straight swap.
How long does it take?
A straight like-for-like swap is usually a one-day job. Moving the boiler, converting from one type to another, or removing a back boiler can take two to three days. A good engineer will tell you up front how long they expect to be on site.
Gas Safe and grants
Only a Gas Safe registered engineer can legally install a gas boiler. Always ask to see the ID card and check the work they are qualified for. It is worth knowing that the Boiler Upgrade Scheme grant is for heat pumps, not gas boilers, so a new gas boiler will not qualify. For more on who can do what, see our guide on Gas Safe work.
How to get a fair quote
- Get a fixed written price rather than a rough figure over the phone.
- Compare like-for-like scope: same boiler grade, same controls, same filter and flush.
- Check the warranty length and who registers it. Many boilers come with a 7 to 10 year guarantee if fitted by an approved installer.
- Read recent reviews from real local customers before you book.
Find a trusted heating engineer near you
You can find and compare plumbers and heating engineers in your area on GotAPal. See who is nearby, read real reviews, and message them directly. GotAPal is free to use and free to list, with no lead fees, ever.
Ready to get started?
Browse trusted tradesAre you a tradesperson? Your business is already listed. Claim it free, no lead fees ever, and get a free digital contact card and QR.
Claim your free listing