New Boiler Cost in the UK

Replacing a boiler is one of the larger one-off bills a household faces, and the quotes that come back often differ by hundreds of pounds for what looks like the same job. The starting point is simple: a new boiler on its own costs around £1,500¹, one official estimate puts the typical price of a new gas boiler at £2,500 to £3,000², and the average replacement across UK homes works out at around £3,700³. So for most homes the fitted price lands somewhere between £1,500 and £4,000, with the installation work, not the appliance, driving most of the difference.

There are ways to soften the bill. Interim boilers, a rental-style approach to replacing a broken heating system, put the upfront cost at around £1,500, which works out at about £12.50 a month to the household⁴. And the job itself is usually quick: a new boiler installation can take anywhere between four to six hours and up to a couple of days⁵. What follows breaks the price down by boiler type, by fuel, and by the installation work that pushes quotes up or down, so a household can read a quote and know which parts of it are fixed and which are negotiable.

Typical UK boiler prices: most households pay £1,500 to £4,000

The headline range hides two separate costs that every quote combines: the appliance and the labour to fit it. The boiler itself is typically upward of £1,000 for a heat-only model⁸, and around £1,500 as a general figure for a new boiler¹. On top of that comes the installer's time, the flue, the pipework and any system changes, which is how an average replacement reaches around £3,700³ and how a heat-only gas boiler installed comes to £2,500 to £4,100⁶.

Where a household sits in that range depends mostly on the job, not the brand. A like-for-like swap, where the new boiler goes where the old one was and connects to the existing pipework, sits at the lower end. Anything that involves moving the boiler, changing its type, or upgrading the system around it pushes the price up, and those items appear as separate lines on a quote so they can be questioned.

For households facing a dead boiler in winter, the interim boiler model is worth knowing about: at around £1,500 upfront, the boiler itself generates a monthly cost to the consumer of about £12.50⁴. That is a different product from a straight purchase, but it shows how the appliance cost and the installation cost separate out.

At the far end of the scale, biomass boilers are in a different price class altogether: the appliance alone can range from £5,000 to £10,000, with installation on top¹. Those are covered in the fuel section below.

Factors that raise or lower what you pay

The single biggest driver is whether the installation is like-for-like. As Ideal Heating puts it: "If you're changing your boiler type from Heat Only to a combi boiler or even a heat pump, this also increases costs further" because the full heating system often needs replacing⁸. A conversion means new pipework, removal of tanks and cylinders, and more labour days; a straight swap does not.

Beyond that, the price of everything around a boiler moves with circumstances rather than with the appliance. Boiler service costs vary with the type of boiler, its age, where you live, and the company you choose⁹. The same factors shape cover and maintenance pricing: renewal prices for British Gas HomeCare are influenced by where you live, your claims history, and the age and model of your boiler¹⁰. Location and the age of the existing system therefore feed into installation quotes too, since an older system presents more unknowns for the installer.

Finally, how the boiler is set up after installation changes what the household gets from it. Energy Saving Trust notes that savings from adjusting flow temperature depend on what the boiler was set to before the change, whether the home was too warm before, and how much the householder is prepared to experiment with the flow temperature¹¹. A new boiler badly set up will cost more to run than an old one set up well.

Boiler type and its effect on the bill

The three main boiler types carry different price tags, mostly because of what surrounds them rather than the unit itself. Heat-only boilers are the cheapest type of boiler to buy⁶, and a heat-only or conventional gas boiler installed comes in at £2,500 to £4,100, a range aimed at larger properties with greater demand and low water pressure⁶. The appliance is cheap; the cylinder, feed and expansion tanks and the larger system around it are where the money goes.

A combi boiler dispenses with the cylinder and tanks, which can make the installation simpler in one sense, but converting from a heat-only or system boiler to a combi means removing that hardware and re-routing pipework, which is exactly the kind of type change that raises costs⁸. The same applies in reverse: a household that later wants a heat pump may need to put a cylinder back in.

Type also interacts with lifespan, which affects the cost per year of ownership. A combi or system boiler typically lasts 10 to 15 years in an average household if it has been regularly serviced and looked after¹. A well-maintained heat-only boiler can generally last between 15 and 20 years⁸, which is one reason the cheapest type to buy can also be the cheapest to own over two decades.

The practical rule for a household reading quotes is to check which type the quote assumes. A quote for a "new boiler" that is actually a conversion from a regular system to a combi, or the reverse, is a different job with a different price, and the two should not be compared line for line with a like-for-like quote.

Fuel options and their price ranges

Most boilers in the UK are fuelled by gas or oil, but sometimes liquid petroleum gas (LPG) or biomass¹². The fuel changes both the purchase price and the shape of the ongoing bill.

Gas is the default and the cheapest to install. Oil and LPG suit homes off the gas grid, and both carry storage and delivery arrangements that gas homes do not have; more detail is on our pages for oil boilers and LPG heating.

Biomass is where the price range widens dramatically, and where two independent figures differ. Uswitch's guidance puts biomass boiler installation at £19,000 to £31,000⁶. The same guidance records an Energy Saving Trust estimate that installation of automatic-fed wood pellet boilers is between £8,000 and £15,000⁶. The two figures differ, and a household considering biomass can treat the range as spanning both, with the final price depending on the size and specification of the system. On running costs, biomass is typically cheaper than gas and oil, currently costing around £400 to £600 a year based on average medium usage of 12,500 kWh per year⁶.

There is grant support for biomass, but only in narrow circumstances. The Boiler Upgrade Scheme provides £5,000 towards the cost and installation of a biomass boiler, but only in rural locations and in properties not connected to the gas grid¹³. Biomass boilers are an eligible technology under the scheme¹⁴, and the average total quote for a biomass installation under the scheme, including grant value, was £16,223 in the official statistics for 2024 to 2025¹⁵.

Fitting charges and what your estimate ought to cover

Installation is where quotes diverge, and it is where a household has the most scope to check what is being charged for. The Centre for Sustainable Energy advises getting at least three quotes from qualified heating engineers before committing to a replacement¹⁶. Three quotes reveal whether a price reflects the job or the company's margin.

A fair quote is itemised enough to show the appliance, the labour, the flue and any system work as separate costs. The time the job takes gives a sense of scale: new boiler installations can take anywhere between four to six hours up to a couple of days⁵. A quote for a two-day job that assumes one day of labour, or the reverse, is worth questioning.

There are also physical requirements that a quote accounts for. A boiler housed in a cupboard is fitted with at least 60 mm clearance¹⁷. Flue work, in particular, is a common source of extra charges: moving a boiler or changing the flue position adds materials and labour, and our page on boiler flues covers the rules on positions and clearances.

Who does the work is not negotiable. Gas work must be carried out by a Gas Safe registered engineer, and if problems arise with a boiler, the advice is to contact a Gas Safe registered engineer to check it¹⁸. A quote from an installer makes their registration easy to verify, and our page on boiler installation covers the process and the rules in full.

After installation, the boiler is serviced annually to ensure that it stays in good working order and maintains its efficiency¹⁶. Some installers bundle a first service into the price; whether that is included is visible on the quote.

Day-to-day costs and savings after upgrading

A new boiler is not, on its own, a large saving on bills. What it does is remove the waste that an old boiler carries: new boilers in the UK are all required to be condensing boilers, which are at least 90% energy efficient¹⁹. Replacing a boiler that is well past its best therefore cuts the gas needed to deliver the same heat, but the size of the saving depends on how bad the old boiler was.

The cheapest savings come from settings, not hardware. Lowering the flow temperature on a combi boiler is reported to cut around £65 a year²⁰, and how much a household saves depends on what the boiler was set to before the change, whether the home was too warm before, and how much the householder is prepared to experiment with the flow temperature¹¹. Our page on boiler flow temperature covers this in detail.

Looking ahead, the economics shift. Nesta's modelling of a cheaper-electricity scenario puts the total annual cost at £1,120 for a heat pump and £1,190 for a gas boiler installed in 2030, after subsidy²¹. For boilers installed in 2030, the annualised total cost ranges from £710 to £1,960 depending on the archetype of home²¹. A replacement boiler bought now will still be running when those comparisons bite.

Two further figures are worth having. Replacing a gas boiler as part of a hybrid system is cheaper than a full-size model: the price for a slightly smaller boiler may be just 10 to 20% lower²², which shows how little of a boiler's price scales with output. And Energy Saving Trust puts the saving from a boiler upgrade at £440 in Northern Ireland¹², a figure that reflects that nation's different fuel mix.

Annual servicing: expect £60 to £150

Once the boiler is in, the ongoing cost is servicing. The average cost of a boiler service varies from around £90 to £100⁷, and according to Checkatrade, the average cost of a boiler service as of March 2026 is £100 including VAT⁷. A gas boiler service typically costs £80 to £120 including VAT, and an oil boiler service around £90 to £95⁷.

The frequency is not optional in practice. It is recommended that a boiler is serviced at least once a year, in other words every 12 months¹⁷, and the boiler is serviced annually to ensure it stays in good working order and maintains its efficiency¹⁶. Annual servicing is also typically a condition of a manufacturer's warranty, so skipping it can cost more than the service fee if a fault later appears; our page on boiler warranties explains the conditions.

A service takes about an hour for a system boiler⁷. What it does not include is repairs: if the service uncovers a problem, the additional bill could average £120 to £750⁷, and typical repairs run between £120 and £750 depending on the parts and labour needed²³. A household budgeting for a boiler therefore plans for the service plus the possibility of a repair in an older system.

For households weighing cover against pay-as-you-go servicing, the same variables apply: prices depend on the type and age of the boiler, where you live, and the company you choose⁹, and renewal prices for British Gas HomeCare are influenced by where you live, your claims history, and the age and model of your boiler¹⁰. Our page on boiler cover and service plans compares the options.

Boiler lifespans and the right moment to upgrade

Lifespan is what turns the purchase price into an annual cost. Most boilers are designed to last around 15 years²⁴, and a boiler typically lasts 10 to 15 years in an average household if it has been regularly serviced and looked after¹. In some cases, boilers can go longer than 15 years and even up to 20 years¹. A well-maintained heat-only boiler can generally last between 15 and 20 years⁸, and the current lifespan of a boiler is around 15 years as the planning rules assume²⁵.

The replacement decision has a rough age threshold: if a boiler is over fifteen years old, it could be time to replace it²⁴. But age alone is not the test. The repair-or-replace calculation also depends on the state of the system: if you have a newer boiler, under eight years old, repairing it is likely a more sensible idea than replacing it²³. Below eight years, repairs usually win; above fifteen, replacement usually does; in between, the frequency and cost of repairs decide.

A boiler that needs annual attention, that has had a repair in each of the last two years, or whose parts are becoming hard to source is telling the household something regardless of its nominal age. Set against a fitted cost of around £3,700 on average³, a single repair at £120 to £750²³ is bearable; a pattern of them is not.

Two habits extend the life that is paid for. The first is the annual service already covered above¹⁷. The second is watching the pressure: it sits between 1 and 2 bar¹⁷, and a system that keeps losing pressure has a leak or a fault that will shorten the boiler's working life if ignored. Our page on boiler pressure covers the normal range and topping up.

Boilers and Britain's shift towards greener heating

A new boiler is a fifteen-year commitment, and the policy landscape over that period is moving away from gas. The Climate Change Committee's Sixth Carbon Budget pathway assumes that "By the early 2030s all new cars and vans and all boiler replacements in homes and other buildings are low-carbon, largely electric"²⁶. That is a pathway rather than a law, but it indicates the direction a household is buying into.

The main financial lever today is the Boiler Upgrade Scheme, which provides upfront grants of up to £7,500 to encourage property owners to replace existing fossil fuel heating with a low-carbon alternative²⁷. The scheme covers properties in England and Wales²⁸, and eligibility requires the property to be replacing a fossil fuel heating system, such as gas, oil or LPG, or an electric heating system, excluding existing heat pumps²⁹. Fossil fuel heating systems include oil, gas, electric or LPG³⁰, and biomass boilers are among the eligible technologies¹⁴.

The scheme's own statistics show how the market is responding: the average total quote including grant value was £13,433 for an air source heat pump, £27,924 for a ground source heat pump and £16,223 for biomass in 2024 to 2025¹⁵. For biomass specifically, the lower quartile installation capacity in England and Wales in the second quarter of 2026 was 19.6 kW³¹, which gives a sense of the scale of system the grant is supporting.

Wales is signalling the same shift through its own programme. Under the New Warm Homes Programme, gas boiler replacements will move to be the exception rather the default, with the programme instead favouring repair of fossil fuel assets and a shift towards low-carbon heating³².

What this means for a household replacing a boiler now is a genuine tension. A modern condensing boiler is at least 90% energy efficient¹⁹ and represents a real improvement on an old appliance. But it also locks in fifteen years of gas dependence, at a time when official pathways expect boiler replacements themselves to be low-carbon by the early 2030s²⁶. A household with a working boiler under eight years old is likely better off repairing it²³. A household facing a dead boiler can price a heat pump alongside the replacement, using the £7,500 grant²⁷, before committing. Our pages on heat pumps compared with boilers, the gas boiler ban question and heating grants in each nation take those comparisons further.