CoverMapNew boiler cost by type (2026)
| Job | Typical installed price |
|---|---|
| Like-for-like combi swap | £1,800–£3,500 |
| Premium combi | £3,000–£4,500 |
| System boiler replacement | £1,800–£3,500 |
| Regular (heat-only) boiler replacement | £1,800–£3,000 |
| Back boiler to combi conversion | £3,500–£6,000 |
| Oil boiler replacement | £4,500–£5,500 |
| Electric boiler | £1,700–£4,500 |
Source: Heatable 2026 guide, based on an analysis of about 2,000 quotes from early 2026. The median price for a standard combi replacement was £2,300, and most were between £2,150 and £3,000.
Which type do you need? A combi heats water on demand and needs no tank, so it suits most flats and smaller homes. A system boiler uses a hot water cylinder and suits homes with more than one bathroom. A regular (heat-only) boiler also has tanks in the loft and is common in older homes. Replacing like with like is usually the cheapest and quickest job: Uswitch says a straight swap takes about 4–6 hours, while changing type can take up to 2 days.
What adds to the cost
| Extra | Typical cost |
|---|---|
| Power flush (cleaning the system) | £300–£750 (average about £500) |
| Smart thermostat | £100–£250 |
| Upsizing the gas supply pipe | £100–£400 |
| New hot water cylinder | £350–£1,400 |
| Moving the boiler, changing the flue or removing a back boiler | Adds to labour time; included in the conversion prices above |
Source: Which? boiler price guide.
BOXT gives a fixed online quote in about two minutes with no home visit, with installation from £1,745, next-day fitting when you order before 3pm, and finance from £12 a month.
Get a BOXT quoteHow long does a boiler last?
Baxi says a boiler should last 10–15 years if it is serviced every year. Signs it may be time to replace yours include:
- frequent breakdowns or repair bills
- radiators that are slow to warm up
- weak or inconsistent hot water
- unusual noises, or pressure that keeps dropping
- rising heating bills
- not enough hot water after an extension or for several taps at once
Baxi, citing the Energy Saving Trust, says replacing an old gas boiler with an efficient model and proper controls could save up to £315 a year.
The rules: Gas Safe and building regulations
- Gas Safe Register: by law, anyone working on gas appliances in the UK must be Gas Safe registered. Ask to see the engineer’s Gas Safe ID card.
- Building regulations: replacing a boiler is notifiable work in England. A registered installer can self-certify it. You should get a commissioning certificate (such as Benchmark), and the council later sends a building regulations completion certificate. Keep both, as you will need them when you sell the home.
- Efficiency: new gas boilers must be at least 86% efficient and are normally condensing boilers.
Are gas boilers being banned?
Not in existing homes. You can still replace a gas boiler with a new one. The government’s Warm Homes Plan (January 2026) sets no date to stop gas boilers being fitted in existing homes.
New-build homes are different. Under the Future Homes Standard, new homes built under the new rules will need low-carbon heating such as heat pumps. The standard comes into force on 24 March 2027 for most buildings, with a transitional period to 24 March 2028. Some older articles say gas boilers were banned in new homes “from 2025”; that was an early target and is out of date.
Grants for a new boiler in 2026
| Scheme | What it offers | Status (October 2026) |
|---|---|---|
| ECO4 | Free or subsidised heating and insulation, including boiler replacement, for lower-income households in homes rated EPC D–G | Ends 31 December 2026. Some councils are already closed to new applications |
| Great British Insulation Scheme | Mainly single insulation measures | Ended 31 March 2026 |
| Boiler Upgrade Scheme | £7,500 off a heat pump (not a gas boiler). £9,000 for air or ground source heat pumps in off-gas-grid homes in England and Wales, July 2026 to March 2027 | Open. You must own the home and use an MCS-certified installer, who applies for you |
| Warm Homes Plan | £15bn this Parliament to upgrade up to 5 million homes, including up to £1.7bn for low- or zero-interest loans | Being rolled out from 2026 |
To check ECO4 eligibility, contact your local council or energy supplier soon, as the scheme closes at the end of 2026.
Warranties and paying for a new boiler
| Brand | Typical manufacturer cover |
|---|---|
| Worcester Bosch | 5–10 years (guarantee) |
| Ideal | 5–10 years |
| Vaillant | 5–10 years |
| Viessmann | 5–12 years |
| Baxi | 3–10 years |
To keep the warranty valid, use a Gas Safe installer, register the boiler with the manufacturer within 30 days, and have it serviced every year. Once the warranty ends, boiler cover can protect against repair bills.
Finance: many installers offer monthly payments. Which? suggests looking for 0% APR deals over 2–4 years and only borrowing what you can clear within four years. Check the total amount repayable, not just the monthly cost.
How to get the best price
- Get at least two or three quotes. Online fixed-price installers and local Gas Safe engineers can both be competitive.
- Replace like with like where it still suits your home, as conversions cost more.
- Check what is included: system flush, filter, controls, removal of the old boiler, and registering the warranty.
- Compare warranty length as well as price.
- Don’t wait for a breakdown if your boiler is over 10 years old: planning ahead lets you compare properly.
Frequently Asked Questions
How much does a new combi boiler cost in 2026?
A like-for-like combi replacement typically costs £1,800–£3,500 fitted. The median quote in early 2026 was about £2,300. Premium combis cost £3,000–£4,500, and converting from a back boiler costs £3,500–£6,000.
Can I still get a gas boiler in 2026?
Yes. There is no ban on replacing a gas boiler in an existing home. The Future Homes Standard will require low-carbon heating in new-build homes from 24 March 2027 (with a transitional period), but it does not affect replacements in existing homes.
Are there grants for a new boiler?
ECO4 can fund a boiler replacement for eligible lower-income households, but it ends on 31 December 2026 and some areas have closed to new applications. The Boiler Upgrade Scheme gives £7,500 (or £9,000 in some off-gas-grid homes) towards a heat pump, not a gas boiler.
How long does it take to fit a new boiler?
A like-for-like swap usually takes about 4–6 hours. Changing the type of boiler or moving it can take up to 2 days.
Do I need building regulations approval for a new boiler?
Yes, but a Gas Safe registered installer can self-certify the work, so you do not need to contact building control yourself. You will receive a completion certificate from the council afterwards.
How long does a boiler last?
Around 10–15 years if it is serviced every year, according to Baxi.
Sources
- Heatable – How much do new boilers cost? (2026)
- Heatable – Boiler warranties explained
- Which? – Boiler prices: how much does a new boiler cost?
- Uswitch – New boiler cost guide
- Baxi – How long does a boiler last?
- Planning Portal – Boilers and building regulations
- Doncaster Council – Gas Safe Register
- GOV.UK – Warm Homes Plan
- Energy Saving Trust – Boiler Upgrade Scheme
- UK Parliament – Written statement on the Future Homes Standard (24 March 2026)
- Oxford City Council – ECO flexible eligibility
- BOXT – Boilers