Our new boiler cost guide covers everything you need to help budget for replacing your boiler. We include the average cost of a new boiler, installation, additional expenses, and the financial support available.

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Your boiler is a key part of your home's heating system, typically lasting between 10-15 years before it could start costing you money. An older boiler is generally less efficient and can lead to higher energy bills. It's also more likely to break down, so you could be shelling out for boiler repairs more often than you'd like. Buying a new boiler is a major purchase, so most people want a clear idea of the likely cost before they start getting quotes. In the UK, a new boiler typically costs between £1,200 - £10,000 for supply only. Once installation and typical extras are included, the total cost usually comes in at £3,000 - £15,000.

How much does a new boiler cost?

The cost of a new boiler depends on the type of boiler, the fuel it uses, the manufacturer, and how straightforward the installation is.

As a general guide, new boiler supply costs usually range from £1,200 - £10,000, before installation.

N.B. The costs outlined in the table above should be used as a guide only.

• New boiler costs generally sit between £1,200 - £10,000. This is for supply only, not including installation

• With labour and typical extra expenses included, you can usually expect your total bill to be between £3,000 - £15,000

For an accurate new boiler price, contact an approved heating engineer for a quote.

New boiler costs at a glance

• Supply-only boiler costs: typically £1,200 - £10,000

• Typical boiler installation costs: £1,000 - £2,000

• Average total cost of a new boiler and installation: £3,000 - £15,000

• Like-for-like combi boiler replacement (supply + install): usually £2,500 - £4,000

• Simple boiler installation time: typically 4 to 6 hours

• Changing boiler type or moving the boiler: usually increases the overall cost

New boiler costs by type

There are several different types of boilers available, including combi, system, conventional, electric, and biomass.

In this section, we look at new boiler prices by type, their running costs, and the pros and cons to be aware of.

1. Combi boiler costs

Combi boilers are one of the most popular choices in the UK because they provide heating and hot water on demand from a single unit.

On average, a new combi boiler costs around £1,500 before installation.

• Gas combi boilers use natural gas and are a common choice for any home that’s connected to the gas network

• Oil combi boilers are an option for homes without an existing gas connection and use an oil storage tanker

• LPG combi boilers use liquefied petroleum gas (or LPG) and are an energy-efficient way of providing hot water

• Electric combi boilers function slightly differently as they heat water by passing it over a hot element instead of burning fuel

The average cost of replacing a combi boiler

• Replacing an old combi boiler with a new one in the same location costs around £2,500 - £4,000(supply and install)

• Replacing a system boiler with a new combi boiler costs on average £4,000 (supply and install)

• Replacing a conventional boiler with a new combi boiler costs on average £4,000 (supply and install)

Switching from one type of boiler to another can require more work and additional parts, so expect to pay more than if you're replacing like-for-like.

Pros and cons of a combi boiler

Combi vs condensing boilers – what’s the difference?

Has the time come for a boiler replacement? Then you might be wondering what’s best: combi vs condensing boilers? Here’s the truth.

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Gas combi boiler cost

The average gas boiler cost for supply and installation is £3,000.

Gas combi boilers are energy-efficient and compact, meaning lower energy bills. You can also expect hot water on demand, which is a huge plus during the colder months.

On average, expect the running cost of a gas combi boiler to be around £120 per month.

Electric combi boiler cost

The average electric combi boiler cost for supply and installation is £3,000.

Electric combi boilers are usually more compact, quieter, and cheaper to install than a gas boiler. They also tend to better for the environment.

Electric combi boiler running costs

While these boilers are quick and easy to repair, electric combi boiler running costs can be expensive.

Based on the UK average of 24.50p per kWh, running a 12kw electric boiler at 70 hours a month will cost £206 per month.

In comparison, the average monthly gas boiler cost is about £120 per month.

Oil combi boiler cost

The average oil combi boiler cost for supply and installation is £4,000.

An oil combi boiler can be a good alternative if your property isn’t connected to the main gas or electric network. However, the installation and running an oil boiler is often higher than some other heating systems.

Cost of running gas central heating

In the UK, most of us are connected to mains gas. But if you’re off the main grid, you’ll need to look at alternatives. So, what exactly are the options when it comes to gas central heating and what does it cost?

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2. System boiler costs

System boilers work with a hot water cylinder and are often a good fit for larger homes that need hot water in more than one place at the same time. This type of boiler is fed by the mains water supply.

• Upgrading to a newer system boiler cost is around £3,000 (supply and installation)

• However, a new high-end system boiler could cost around £2,500 + (supply only)

As with combi boilers, system boilers can be fuelled by oil, gas, or electricity:

• A new oil system boiler costs starts at around £2,000 (supply only)

• The average new gas system boiler cost is around £1,500 (supply only)

• The average new electric boiler cost (system boiler) is £1,750 + VAT (supply only)

Pros and cons of a system boiler

Find boiler replacement services near me

Is your boiler showing signs of wear and tear, struggling to heat your home, or costing you more in repairs than it should? It might be time for a replacement. In which case, the first step is to find a qualified heating engineer.

Learn more

3. Conventional boiler costs

If combi and system boilers don’t fit your requirements, there’s the option of conventional or ‘heat only’ boilers.

These are often cheaper than other boilers but require a hot water cylinder and a cold water tank. Conventional boilers heat previously stored water until it is ready to be used and are a great option for large homes.

• On average, a conventional boiler will set you back around £3,000 (supply and installation)

The size you need will depend on your home's size and budget.

Pros and cons of a conventional boiler

It's worth noting that certain ‘heat only’ boilers do not supply hot water, so they'll only heat your home.

For professional advice, contact a local heating engineer to select the best boiler for your needs.

4. Condensing boiler costs

Most modern boilers are condensing boilers, designed to recover more heat from the flue and improve efficiency. Condensing boilers come in two varieties — regular and combi.

• A regular boiler has a hot water tank and can supply energy to a large-sized house

• The combi-condensing boiler does not have a tank, making it more compact

As a ballpark average, the cost of a new condensing boiler is normally around £1,500 (supply only).

Installation costs for a condensing boiler are usually around £1,500.

Pros and cons of a condensing boiler

Instead of allowing heat to be wasted in the flue, these boilers are designed to not only trap the heat but also use the latent heat from condensation.

As a result, these boilers are designed to be highly efficient and can help reduce wasted heat.

5. Biomass boiler costs

Biomass boilers are much more expensive than standard gas, oil or electric options, but they can appeal to people looking for a lower-carbon heating system.

On average, the price of a biomass boiler is around £10,000 (supply only). The cost of a biomass boiler is considerably more than other types of boiler.

However, before dismissing this option, you may be encouraged to learn that biomass fuel costs are lower, they're eco-friendly, and government grants are available to help with the cost of installation.

The average total costs of supplying and installing a biomass boiler are:

• Manually-fed biomass boiler (logs) - £19,000

• Automatically-fed biomass boiler (pellets) - £31,000

Biomass boiler installation costs start from around £5,000 for a small domestic boiler.

Biomass boiler fuel costs per tonne

A biomass boiler, unlike a gas or oil boiler, uses wood pellets that have been sustainably sourced. Here are some of the average fuel costs per tonne for a biomass boiler in the UK:

• Wood chips – £175 per tonne

• Wood logs – £650 per tonne

• Wood pellets – £750 per tonne

Biomass boiler fuel costs per kWh

To help you weigh up the ongoing running costs of a biomass boiler, here are the equivalent fuel costs per kWh:

• Biomass woodchips – 4.17p per kWh

• Biomass logs (kiln dried logs) – 12.75p per kWh

• Biomass pellets – 15.31p per kWh

Pros of a biomass boiler

• Uses renewable energy

• Lower carbon footprint

• Government grants are available to help with the cost of installation

Cons of a biomass boiler

• Higher initial installation cost

• Significant space needed for fuel storage

How much does boiler installation cost?

Installation is a big part of the total price of a new boiler.

Most boiler engineers charge a day rate, with the average boiler installation labour cost sitting at around £300 per day.

• A simple, like-for-like boiler installation: 4 – 6 hours

• Converting a regular boiler to a combi boiler: 1.5 – 2 days

• Moving the location of the boiler: variable

We always recommend hiring a qualified heating engineer who is accredited to work with the type of boiler you choose for your boiler installation.

• Gas boilers must be installed by a Gas Safe Registered engineer

• Oil boilers must be installed by an OFTEC registered technician

• Electric boilers are best installed by a boiler installation company that will have all the skills necessary for dealing with plumbing, electrics, and gas (if disconnecting an existing gas boiler)

What affects the cost of a new boiler?

The final price you pay for a new boiler isn’t just about the unit itself. Installation complexity and your system condition can make a big difference to the final bill.

Key factors that influence cost include:

• Type of boiler: combi boilers are often cheaper to install than system or conventional boilers, which require additional tanks or cylinders

• Fuel type: gas, oil, electric and biomass systems all come with different equipment and installation requirements

• Whether you're replacing like-for-like: swapping an old combi boiler for a new combi in the same location is usually the simplest and most cost-effective option

• Installation complexity: costs can rise if pipework needs updating, the boiler needs relocating, or access is difficult

• Warranty length and manufacturer: higher-end models and longer warranties can increase the upfront cost but may offer better long-term value

• Location of your property: labour costs are typically higher in London and the South East than in other parts of the UK

On Checkatrade, you'll only find trades who meet our high standards and pass up to 12 checks.

Additional costs to budget for

The headline boiler price is only part of the overall cost. Depending on your system and the installer’s recommendations, there may be a few extra items to factor into your budget.

Common additional costs include:

• Powerflushing: a powerflush clears sludge and debris from your heating system before a new boiler is installed. Typical cost: around £1,000 inc VAT

• Magnetic filters: these help protect the boiler by capturing debris circulating in the system. Typical cost: £60 - £160, plus £50 - £150 for installation

• Smart thermostats or heating controls: many homeowners choose to upgrade controls at the same time as installing a new boiler. Typical cost: around £150 (supply only)

• Moving the boiler: relocating the boiler to a different room or wall can add significantly to installation time and cost. Typical labour cost: around £1,000

• New radiators: older radiators can be less efficient and may not perform well with a new boiler. Typical labour cost to replace a radiator: around £200

It’s always worth asking your installer exactly what is included in the quote so there are no surprises later.

How much does it cost to replace a boiler?

As we've already outlined, the cost of a new boiler will depend on the type of boiler you choose, various factors surrounding installation, and whether you select any extras such as new rads, magnetic filters, or Wifi-enabled controls. Let's look at the cost of a few common scenarios.

Like-for-like combi replacement

To replace a combi boiler with another combi boiler costs on average £2,500 - £4,000 (supply and installation).

Regular to combi conversion

Converting a regular boiler to a combi boiler costs around £4,000 (supply and installation) and usually takes about two days.

The cost includes the price of laying new pipework as well as removing and discarding your old boiler and water cylinder.

System to combi conversion

If you want to replace your system boiler with a combi boiler, your boiler conversion cost will be about £4,000 (supply and installation). This conversion will take up to around three days.

Back boiler to combi conversion

The average back boiler to combi boiler conversion cost is around £4,000 (supply and installation).

The total cost will depend on several factors, including the new boiler you buy, the location of the existing boiler, and any new pipework needed.

Cost to move a boiler

If you're in the market for a new boiler, it could be a good time to consider moving its location.

The ballpark labour cost to move your boiler will be around £1,000.

The cost will largely depend on the complexity of the job. The more complicated an installation is, the more it will cost. Our guide to the cost of moving a boiler contains more detailed information.

Central heating installation cost in the UK in 2026

A new central heating system is a big investment for any homeowner or landlord, and the price can vary depending on the type of boiler or heater, the number of radiators and other key components.

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How long does it take to fit a new boiler?

Boiler installation can be a fairly quick job or a more involved project, depending on what’s being replaced.

Typical timeframes are:

• Like-for-like boiler replacement: 4 to 6 hours

• Regular to combi conversion: 1.5 to 2 days

• System to combi conversion: often up to 3 days

• Boiler relocation: timing varies depending on the complexity of the job

If you’re changing boiler type, moving the boiler, or adding extra work such as new controls or radiators, expect the installation to take longer.

Your installer should be able to give a clear timeframe once they’ve assessed your system and home layout.

New boiler cost calculator

Our boiler cost calculator can be a useful starting point if you’re keen to get an idea of costs before getting quotes.

Remember, your total cost will usually depend on the type of boiler you choose, installation labour, any conversion work and whether you add extras such as thermostats, filters or radiators.

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Always arrange for a qualified local heating engineer to assess your property, discuss your requirements and provide a written quote before you go ahead.

Is it worth replacing an old boiler?

In many cases, it's worth replacing an old boiler, especially if your current boiler is around 10 to 15 years old, breaking down more often, or becoming expensive to run.

A newer boiler can improve efficiency, reduce the risk of breakdowns, and make heating and hot water feel more reliable day to day.

While replacement is a significant upfront cost, it can make more sense than continuing to pay for repairs on an ageing system.

Wondering if you should repair or replace a boiler? When it comes to getting a job done right, we're here to help. From the signs you need a new boiler to the planning process you need to remember, we're here to help.

What size boiler do you need?

Choosing the right size boiler matters just as much as choosing the right type.

In the UK, boilers are sized by their output in kilowatts (kW), not their physical size. As a general rule, the more radiators, bathrooms and bedrooms you have, the higher the output you’ll need.

One of the easiest ways to work out which size boiler you need is to count the number of radiators, bathrooms and bedrooms you have in your home:

For larger homes (4+ bedrooms and 3+ bathrooms), you'll most likely need a system or regular boiler to efficiently meet your heating needs.

Issues if your boiler is too big (oversized)

Bigger isn't always better when it comes to boilers, as having an oversized boiler can cause numerous issues, including:

• More power is needed to heat the same volume of water

• Wasted energy

• Higher energy bills

• Poor or unreliable performance

Problems if your boiler is too small (undersized)

Nobody wants to wake up to a cold house and freezing shower on a cold winter's morning. If your boiler is undersized for your home then you could be dealing with these issues:

• It won't be able to keep up with the heating demands of your home

• Lack of hot water

• Lack of heating

Thankfully, modern boilers are much more efficient than their predecessors so it's easier to work out the size of boiler that you need for your home.

If in doubt, speak to your local experienced boiler fitters for their professional advice and guidance on choosing the right size boiler.

Can you fit a boiler yourself?

Fitting a new boiler is not a DIY job.

Gas boilers must be installed by a Gas Safe registered engineer, while oil boilers must be fitted by an OFTEC registered technician. Even electric boilers usually involve plumbing and system work that needs professional expertise.

A poor installation can affect safety, efficiency and warranty cover — this is one job where professional fitting is essential.

Available grants for new boilers

Replacing a boiler is a major expense, so it’s understandable that many homeowners look into possible grants or support schemes first.

New boiler grants in England and Wales

The Boiler Upgrade Scheme offers grants to cover part of the cost of replacing fossil fuel heating systems with a heat pump or biomass boiler.

Available grants

• £7,500 towards an air source heat pump

• £7,500 towards a ground source heat pump (including water source heat pumps and those on shared ground loops)

• £5,000 towards biomass boiler costs

(Information correct at time of publishing)

New boiler grants in Scotland

There are two options funded by the Scottish Government: The Warmer Homes Scotland Scheme and Home Energy Scotland Grant and Loan.

Grants and interest-free loans are available to eligible households to help with energy-saving home improvements, including central heating, loft and wall insulation, draught-proofing, and renewable systems for generating your own energy.

New boiler grants in Northern Ireland

The Affordable Warmth Scheme (NI) helps low-income households and those in fuel poverty to make energy-efficiency improvements. This can include getting a new boiler fitted, subject to eligibility and assessment.

Looking to save on the cost of boiler installation? Take a look at our guide to the current green home grants and their eligibility criteria.

New boiler cost checklist

• Decide whether you’re replacing like-for-like or changing boiler type

• Check what size boiler your home actually needs

• Ask whether installation includes extras such as a magnetic filter or thermostat

• Compare quotes from qualified local engineers

• Confirm whether old boiler removal, powerflushing and controls are included

• Check the warranty and who must install the boiler to keep it valid

When should you speak to a heating engineer?

It’s usually worth speaking to a heating engineer before your boiler fails completely, particularly if you’re starting to notice changes in performance.

Common signs it may be time to get advice include:

• Your boiler is 10 to 15 years old

• Repairs are becoming more frequent

• Heating or hot water feels unreliable

• Energy bills are rising without a clear reason

• Parts are becoming harder to find

• Your boiler struggles to keep your home warm

An engineer can assess your current system, explain your options, and provide a realistic estimate for replacement if needed.

Find qualified boiler installers near you

If you’re ready to replace your boiler, comparing quotes from a selection of qualified local heating engineers is the best place to start.

A good installer can recommend the right boiler for your home, explain what’s included, and help you avoid paying for extras you don’t need.

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