UK cost guide · September 2026
How much does a new boiler cost in 2026?
Replacing a combi boiler with a new one costs about £2,500 to £3,200 including VAT for a mid-range model, fitted, in an average UK area outside London (about £2,900 to £3,800 in London). Changing a system boiler to a combi costs £3,200 to £4,200 and a regular boiler £3,700 to £5,000, because the hot water cylinder (and with a regular boiler the loft tanks) comes out. Swapping a system or regular boiler and keeping the cylinder costs £2,700 to £3,500. An oil boiler costs £3,000 to £4,500, or £4,000 to £5,500 for an oil combi.
Work out your new boiler cost
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Already have a heating engineer’s price? Check where your quote sits against this range. Still deciding what to do first? Read where to start a home renovation.
New boiler prices in 2026
Ranges are for a typical home outside London, including VAT, before fees and contingency. Use the calculator for your region and finish.
| Type | Basic | Mid-range | Premium |
|---|---|---|---|
| Combi boiler, like-for-like swap | £2,000 to £2,500 | £2,500 to £3,200 | £3,200 to £4,000 |
| System boiler to a combi | £2,700 to £3,500 | £3,200 to £4,200 | £3,900 to £5,000 |
| Regular boiler to a combi | £3,200 to £4,300 | £3,700 to £5,000 | £4,400 to £5,800 |
| System or regular boiler swap, keeping the cylinder | £2,200 to £2,800 | £2,700 to £3,500 | £3,400 to £4,300 |
| Oil boiler, regular or system, like-for-like | £2,500 to £3,300 | £3,000 to £4,500 | £4,000 to £5,500 |
| Oil combi boiler, like-for-like | £3,500 to £4,500 | £4,000 to £5,500 | £5,000 to £6,500 |
New boiler costs by region
Labour costs vary across the UK far more than materials. New boiler prices in London run about 18% above the UK average outside London, and in Northern Ireland about 9% below it.
| Region | Mid-range cost |
|---|---|
| UK average (outside London) | £2,500 to £3,200 |
| London | £2,900 to £3,800 |
| South East | £2,700 to £3,400 |
| East of England | £2,600 to £3,300 |
| South West | £2,500 to £3,300 |
| West Midlands | £2,500 to £3,200 |
| East Midlands | £2,400 to £3,100 |
| Scotland | £2,400 to £3,100 |
| North West | £2,400 to £3,100 |
| Yorkshire and the Humber | £2,400 to £3,100 |
| Wales | £2,400 to £3,000 |
| North East | £2,300 to £3,000 |
| Northern Ireland | £2,300 to £2,900 |
Which region is my town in? Brighton, Oxford and Southampton are in the South East; Cambridge and Norwich in the East of England; Bristol, Bath and Exeter in the South West; Birmingham and Coventry in the West Midlands; Nottingham and Leicester in the East Midlands; Glasgow and Edinburgh in Scotland; Manchester and Liverpool in the North West; Leeds, Sheffield and Hull in Yorkshire and the Humber; Cardiff and Swansea in Wales; Newcastle and Sunderland in the North East; and Belfast in Northern Ireland. Somewhere else? Type your postcode into the calculator above and it says which region’s prices it uses.
Want it for your area? See local prices and council building control fees for 92 council areas in England and Wales (not every council yet).
Which boiler job is yours?
The job matters as much as the boiler you choose. A combi heats water as you use it, straight from the mains, with no hot water cylinder. A system boiler heats a hot water cylinder, with no tank in the loft. A regular boiler heats a cylinder fed by a cold water tank in the loft. Changing to a combi takes the cylinder out, and from a regular boiler the loft tanks too, so it costs more than a like-for-like swap. Every job has Basic, mid-range and Premium prices: the finish is mostly the boiler’s brand and warranty. The table above prices each job.
Open a job in the calculator: system to combi, regular to combi, keeping the cylinder or an oil boiler.
A bigger gas pipe from the meter. A new boiler, especially a combi in place of a regular boiler, can need more gas than the old pipe from the meter can carry. A new pipe costs about £300 to £800 including VAT. Our ranges leave it out unless you tick it in the calculator, so ask the engineer whether yours needs one.
Oil boilers. Our oil prices are for a like-for-like swap that keeps the existing oil tank and supply line. Not included: a new oil tank (about £2,200 to £2,800) or a new oil supply line. In England and Wales the installer should be registered with a competent person scheme for oil heating; if not, the work must be notified to building control before it starts, for a fee. A replacement oil tank may not be allowed where the old one stood, because of the rules on fire safety and oil pollution (Planning Portal).
Check the water supply first. A combi heats water as you use it, straight from the mains. Ask the engineer to measure your mains water flow and pressure. A home with two bathrooms in use at once may suit a system boiler and cylinder better than a combi.
A power flush. Our boiler prices include the usual system flush. A power flush is a deeper clean for a sludged system: a machine pumps cleaning chemicals through the radiators and pipes. It costs about £480 to £720 including VAT for a typical 3-bed house, and you can tick it in the calculator for any boiler job.
Replacing an unvented hot water cylinder? That is a job of its own: about £1,400 to £2,200 for a mid-range cylinder like for like, including VAT. See unvented cylinder replacement costs.
Not priced yet: moving the boiler to another room, new radiators, and LPG or electric boilers. Get quotes for those.
If a quote is above the range, ask whether it includes work our price leaves out: moving the boiler, new radiators or controls beyond the standard ones. If it includes a new gas pipe from the meter or a power flush, tick that in the calculator to compare like with like.
What a boiler quote should include
Boiler quotes are short, which makes them easy to compare badly. Check each one covers the same things:
| Item | What to check |
|---|---|
| Boiler model and warranty | The exact model, its output in kW and the warranty length. A longer warranty usually means a higher price, and it may depend on yearly servicing. |
| Flue | A new flue is normally fitted. A long or vertical flue costs more. |
| Filter and flush | A magnetic filter and a chemical flush are usually included. A power flush for a sludged system is often extra: about £480 to £720 including VAT. |
| Controls | In England, a new boiler needs time and temperature controls, and a new combi also needs one extra energy-saving measure: weather or load compensation, flue gas heat recovery, or a smart thermostat with automation and optimisation. Each room also needs its own temperature control, usually thermostatic radiator valves, so check whether fitting them is priced. |
| Removal and disposal | Taking out the old boiler and, for a change to a combi, the cylinder and any loft tanks, with the old pipework capped. |
| Gas supply pipe | Whether the engineer has checked that the pipe from the gas meter is big enough for the new boiler, and the price for a bigger pipe if it isn’t. Our range includes it only if you tick it. |
| Oil tank | For an oil boiler: whether the existing tank and oil line are kept, and whether the installer has checked their condition. |
| Hard water | In a hard water area, ask whether a scale reducer or other water treatment is fitted on the water feed to a combi, to slow the build-up of limescale. Scotland’s building standards guidance asks for it where the water is harder than 200 parts per million (Scottish Government); elsewhere, ask the engineer what the boiler maker recommends for your water. |
| Unvented cylinder | If your hot water comes from an unvented cylinder (fed from the mains, with no tank in the loft) and the engineer will work on it, check they have the skills for it. In England and Wales, Gas Safe registration is for gas work (GOV.UK), and it doesn’t cover unvented hot water cylinders: ask for their unvented qualification, or their competent person scheme registration for unvented systems (Approved Document G, paragraph 3.40; the same paragraph for Wales). |
| Commissioning and warranty | The engineer should fill in the Benchmark commissioning checklist, which records that the boiler was set up and checked properly; completing it is a way of meeting the commissioning requirements of the building regulations (Benchmark). Keep it with the boiler’s papers. Ask who registers the boiler’s warranty with the maker, and when you’ll get confirmation. |
| Certificates and carbon monoxide alarm | A Gas Safe registered engineer must fit a gas boiler. In England and Wales they notify the work through Gas Safe Register, which sends you a Building Regulations compliance certificate. Ask for the engineer's Gas Safe number. An oil boiler should be fitted by a technician in a competent person scheme for oil, who notifies building control for you. Fitting a new or replacement boiler means fitting a carbon monoxide alarm too, in every UK nation. Check the quote includes the alarm.Show the rules
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New boiler or heat pump?
A heat pump costs much more to install, but in England and Wales the Boiler Upgrade Scheme grant narrows the gap: £7,500 towards an air source heat pump, or £9,000 until 31 March 2027 for a home with no mains gas that is heated by oil or LPG (Ofgem, GOV.UK). The table uses £7,500. Running costs depend on your insulation, radiators and energy tariff, and they are not compared here.
| Option | Typical cost |
|---|---|
| Like-for-like combi boiler swap, mid-range | £2,500 to £3,200 |
| Air source heat pump, before the grant | £12,000 to £15,000 |
| Air source heat pump, after the £7,500 grant (England and Wales) | £4,500 to £7,500 |
Heat pump installation is zero-rated for VAT until 31 March 2027. The grant is not available in Scotland or Northern Ireland; in Scotland, Home Energy Scotland runs its own grants and loans. See heat pump costs for what a heat pump install includes, and renovation costs if the heating is part of a bigger job.
What's included in these prices
Included
- New boiler and flue
- Removal of the old boiler, and for a change to a combi the cylinder and any loft tanks
- Magnetic filter and system flush (usually)
- Installation and registration by a Gas Safe registered engineer, or for oil a technician in a competent person scheme
- A carbon monoxide alarm, which the rules require with a new boiler
Not included
- New radiators
- Moving the boiler to a new position (often extra)
- Smart controls beyond the standard
- A bigger gas supply pipe from the meter, about £300 to £800, if the new boiler needs more gas than the old pipe can carry (tick it in the calculator)
- A power flush for a sludged system, about £480 to £720 (tick it in the calculator)
- Replacing an unvented hot water cylinder (a job of its own, £1,400 to £2,200)
- For an oil boiler, a new oil tank or oil supply line
What drives the cost
- Type of job. A like-for-like swap is simplest; conversions and relocations cost more.
- Boiler brand and warranty. Longer warranties and premium brands cost more up front.
- System condition. Sludged systems need a power flush, about £480 to £720.
- Gas supply pipe. A new boiler, especially a combi, can need more gas than the old pipe from the meter can carry. Replacing it with a bigger pipe is extra, and one reason a quote comes in above the range.
Planning, regulations and VAT
A gas boiler must be installed by a Gas Safe registered engineer, who registers the work with building control, and a carbon monoxide alarm must be fitted with it (see what a boiler quote should include). In England and Wales an oil boiler should be fitted by an installer in a competent person scheme for oil heating; otherwise the work must be notified to building control before it starts (Planning Portal). Energy-efficient boilers are charged at the standard 20% VAT rate.
Checklist: what to ask heating engineers to confirm
Print this or save it as a PDF, one copy for each quote. Mark each line included, separate or not confirmed as quotes come in. An empty amount means unknown, not free.
| Item | What to confirm | Included? Amount? |
|---|---|---|
| Model | Boiler model and output. | |
| Warranty | Length and conditions. | |
| Extras | Filter, flush, controls and flue. | |
| Water supply | Mains flow and pressure measured, if you are moving to a combi. | |
| Gas pipe | Whether the pipe from the meter is big enough for the new boiler, and the price for a bigger one if not. | |
| Oil tank | For an oil boiler: whether the tank and oil line are kept, and their condition. | |
| Carbon monoxide alarm | Fitted with the new boiler. | |
| Certificates | Gas Safe or oil scheme registration, and building regulations notification. | |
| Hard water | In a hard water area, whether a scale reducer or other water treatment is fitted on the water feed to a combi, to slow the build-up of limescale. | |
| Unvented cylinder | If an unvented cylinder (fed from the mains, with no tank in the loft) will be worked on: the installer's unvented qualification, or their competent person scheme registration for unvented systems. Gas Safe registration doesn't cover unvented cylinders. | |
| Commissioning and warranty | The Benchmark commissioning checklist filled in and left with you, and who registers the boiler's warranty with the maker. |
Questions people ask
Should I get a heat pump instead?
A heat pump costs more to install, but in England and Wales the Boiler Upgrade Scheme grant of £7,500 narrows the gap: see the comparison above and our heat pump costs. Running costs depend on your insulation, radiators and tariff.
Do I need building regulations approval for a new boiler?
You do not apply yourself. A Gas Safe registered engineer must fit a gas boiler. In England and Wales they notify the work through Gas Safe Register, which then sends you a Building Regulations compliance certificate. The engineer must also fit a carbon monoxide alarm.
How much does it cost to change a regular boiler to a combi?
About £3,700 to £5,000 for a mid-range combi, including VAT, in an average UK area outside London (prices reviewed September 2026). It costs more than a like-for-like swap because the hot water cylinder and the loft tanks come out. Add about £300 to £800 if the gas pipe from the meter needs replacing.
How much does a new oil boiler cost?
About £3,000 to £4,500 for a mid-range regular or system oil boiler, or £4,000 to £5,500 for an oil combi, including VAT, swapped like for like with the existing tank kept, in an average UK area outside London.
Is a heat pump cheaper than a new boiler?
Not to install. A mid-range combi swap costs about £2,500 to £3,200, while an air source heat pump for a 3-bed home costs about £4,500 to £7,500 after the £7,500 grant in England and Wales, in an average UK area outside London (September 2026 prices; the boiler includes VAT, and heat pump installation is zero-rated). Until 31 March 2027 a home with no mains gas that is heated by oil or LPG gets £9,000 instead, which takes another £1,500 off.
Sources and method
Our ranges combine published 2026 UK cost guides, industry data and our own survey of council fees. We check them every quarter. They are budget ranges, not quotes: always get at least three detailed written quotes. Read how Estiquote estimates work, or download the full cost data.