New Boiler Cost: How Much is a New Boiler in 2025?
- How much is a new boiler?
- Combi boiler cost
- System boiler cost
- Conventional boiler cost
- Cost of a new boiler: Breakdown by fuel type and models
- New gas boiler cost
- New oil boiler cost
- New electric boiler cost
- New boiler prices per manufacturer in the UK
- How much does boiler conversion cost?
- How much does moving a boiler cost?
- Can government grants reduce new boiler costs?
- Can you get boilers on finance?
- Could a new boiler save you money?
- Frequently Asked Questions
- New boiler costs range from £1,600 to £6,000, which makes the average new boiler cost £3,800, including installation.
- On average, a combi boiler costs £3,800, a system boiler costs £3,300, and a conventional boiler costs £3,550.
- The cost of a new boiler depends on the boiler type, model, and manufacturer. Warranty length and your heating requirements will also affect prices.
- Grants such as the Boiler Upgrade Scheme and ECO4 could save you up to £5,000 towards a biomass boiler or a free boiler replacement for those eligible.
The average new boiler costs £3,800 on average, but what can affect these prices? In this article, we'll walk you through everything you need to know about your new boiler costs and help you save money along the way.
If you’re ready to get started with your boiler replacement, you can search independently for a heating installer who meets your requirements. However, this can take hours, if not days.
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How much is a new boiler?
A new boiler costs £3,800 on average, including installation costs. Unit prices tend to fall around £2,300 on average before installation. The most common boiler type, a combi boiler, will cost £600 to £4,000, with a system boiler costing between £600 and £3,000. Conventional (or ‘regular’) boilers, although less common, can cost £600 to £3,500.
When estimating the cost of a new boiler, you also need to account for installation and labour fees. Typically, these will add £1,000 - £2,000 to your total. We’ve outlined some current market estimates for each boiler type below to give you an idea of prices.
| How much is a new boiler? | |||
|---|---|---|---|
| Type of boiler / Fuel source | Boiler unit costs | Cost including installation | Average total cost |
| Combi | £600 - £4,000 | £1,600 - £6,000 | £3,800 |
| System | £600 - £3,000 | £1,600 - £5,000 | £3,300 |
| Conventional | £600 - £3,500 | £1,600 - £5,500 | £3,550 |
| Electric | £500 - £3,000 | £1,500 - £3,000 | £3,250 |
| Biomass | £6,000 - £12,000 | £9,000 - £20,000 | £14,500 |
As you can see, boiler prices can vary greatly depending on the type of boiler you need. Within these types, other variables such as fuel choice, manufacturer, and extra features can also influence overall costs. In the next section, we’ll look at each boiler type and how these differences might affect your final total.
Combi boiler cost
Installing a new combi boiler costs between £1,600 and £6,000, with an average price of around £3,800. Combi boilers are the most common type of boiler, offering an all-in-one solution for providing heating and hot water.
Combi boilers are best for small and medium-sized homes with up to 2 bathrooms. As they are compact, they can usually be installed in a small space or cupboard, which is ideal for those with less space. This also makes a combi boiler installation quick and easy (reducing labour costs).
| Combi boiler prices per house size | |||
|---|---|---|---|
| Household size | Combi boiler size | Combi boiler unit cost | Average cost (including installation £1,500) |
| Small 1 – 2 bedroom |
18kW – 27kW | £600 – £1,700 | £2,650 |
| Medium 3 – 4 bedroom |
28kW – 34kW | £700 – £2,900 | £3,300 |
| Large 4+ bedrooms |
35kW – 43kW | £800 – £4,000 | £3,900 |
Prices include gas, oil, and LPG models. Installation is priced at £1,500 for demonstration purposes. All prices are estimates only.
Combi boilers offer many advantages for homeowners, but there are also some drawbacks you should consider. Here are some points to think about.
Pros of a combi boiler
- Energy efficiency between 92-94% means a combi boiler can save money on fuel, leading to reduced energy bills (up to £550 per year!).
- With all components in one unit, you save valuable space in your home.
- Hot water is provided on demand (no need to wait for it to warm up in a tank).
Cons of combi boilers
- They struggle to meet very high hot water demand, so they’re less suitable for homes with more than 2 bathrooms.
- Combi boilers are only as strong as the main water pressure in your area. If you live in an area with low water pressure, this might affect your hot water comfort.
- As they don’t have a backup hot water supply (like a system or conventional boiler), they can be a problem if you experience a breakdown or power outage.
If a combi boiler seems like a poor fit for your home - perhaps you have 2 or more bathrooms or a large family - a system boiler might be the better choice. They offer a greater hot water supply, but your overall central heating installation costs can increase due to additional parts.
System boiler cost
A new system boiler will cost between £1,600 to £5,000 to install. On average, you can expect to pay around £3,300. A system boiler is the perfect choice for homes with a higher hot water demand - this could mean 2 or more bathrooms, or large families who need to use multiple outlets at once.
A system boiler works alongside a hot water storage cylinder, meaning you have a large supply of hot water ready to go. However, you will need additional space to store this cylinder and the boiler unit.
| System boiler prices per house size | |||
|---|---|---|---|
| Household size | System boiler size | System boiler unit cost | Average cost (including installation £1,500) |
| Small 1 – 2 bedroom |
9kW – 18kW | £600 – £1,400 | £2,500 |
| Medium 3 – 4 bedroom |
18kW – 26kW | £1,000 – £2,000 | £3,000 |
| Large 4+ bedrooms |
26kW – 40kW | £1,400 – £3,000 | £3,700 |
Prices include gas, oil, and LPG models. Installation is priced at £1,500 for demonstration purposes. All prices are estimates only.
It should be noted that costs can vary during a system boiler installation due to the more complex nature of their setup. For example, a new hot water cylinder can cost £300 - £1,300, a fee you might not need to pay if you already have a cylinder in place.
If you think a system boiler would be the best for your home, there are some pros and cons you should consider. Our list below should help you determine if this boiler type is right for you.
Pros of system boilers
- System boilers can provide hot water to multiple taps and showers simultaneously, making them ideal for larger homes, with 2 or more bathrooms, or larger families.
- With instant access to hot water stored in a cylinder, they ensure a consistent supply.
- Great option to replace a conventional boiler, as they provide the same high levels of hot water without taking up space in the loft with additional tanks.
Cons of system boilers
- While more compact than conventional boilers, system boilers still require space for a hot water cylinder, typically in an airing cupboard - which means they’re not always suitable for smaller homes.
- The hot water supply is determined by the size of the cylinder. Once it’s empty, you will need to wait for it to refill (this can take from 20 to 60 minutes).
- System boilers can be more expensive to install compared to combi boilers due to the additional components and labour required.
Most homes are likely to be suitable for either a combi or a system boiler. However, in some older homes where conventional boilers are already installed, it can be a good option to simply replace the set-up you already have (as it can cut costs). Let's take a closer look at conventional boiler costs.
Conventional boiler cost
A conventional boiler installation can cost between £1,600 and £5,500, with an average price of around £3,550. Conventional boilers are only recommended in situations where you are replacing an existing one. This is because they work alongside a hot water cylinder and a cold water feed tank (which is stored in the loft) - meaning they take up a lot of space, require many parts and take the longest to install.
A conventional boiler is great for properties that require a very high hot water demand, as they can provide a large storage of hot water ready for use. If you’re replacing an existing conventional boiler, you could also benefit from more modern models' efficiency levels.
| Conventional boiler prices per house size | |||
|---|---|---|---|
| Household size | Conventional boiler size | Conventional boiler unit cost | Average cost (including installation £1,500) |
| Small 1 – 2 bedroom |
9kW – 18kW | £600 – £1,600 | £2,600 |
| Medium 3 – 4 bedroom |
18kW – 26kW | £700 – £2,200 | £2,950 |
| Large 4+ bedrooms |
26kW – 40kW | £900 – £3,500 | £3,700 |
Prices include gas, oil, and LPG models. Installation is priced at £1,500 for demonstration purposes. All prices are estimates only.
If you’re considering a conventional boiler replacement, there are a few things you should know. While there are advantages to this set up, there are some down sides. We’ve detailed some of these points below to help you decide.
Pros of conventional boilers
- Conventional boilers offer a large supply of hot water, meaning they can support the use of multiple outlets simultaneously - great for large families.
- They can actually improve your water pressure as they are gravity-fed water from a cold water feed tank in the loft, rather than from the mains supply.
Cons of conventional boilers
- Conventional boilers need significant space for the boiler unit, hot water cylinder, and cold water storage tank, which takes up, not including clearance space around each unit. This can be problematic for homes with limited space.
- These boiler systems can be complicated and costly to install, up to £2,000, due to the multiple components and extensive pipework required.
- The more complex system with multiple components may require more frequent maintenance compared to simpler boiler types.
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Cost of a new boiler: Breakdown by fuel type and models
Installing a new boiler in your home typically costs between £1,600 and £6,000. One of the main reasons these prices vary so greatly is down to the fuel type you wish to use.
The most popular option in the UK is natural gas (as it’s usually the cheapest fuel), but electric, oil, and LPG (Liquefied Petroleum Gas) are also great choices for some households.
In the table below, we’ve listed some estimated costs for boilers based on the fuel types.
| Boiler cost per fuel type | ||
|---|---|---|
| Fuel type | Boiler unit cost | Average cost (including installation £1,500) |
| Gas | £600 – £3,300 | £3,450 |
| Oil | £1,300 – £4,000 | £4,150 |
| LPG | £600 – £3,200 | £3,400 |
| Electric | £600 – £3,000 | £3,300 |
Installation is priced at £1,500 for demonstration purposes. All prices are estimates only.
From this price overview, we see that gas boilers are typically the cheapest option. However, for homes not connected to the national gas grid, LPG and electric boilers offer comparable prices. Oil boilers are also a good option for rural properties, and despite the higher upfront costs, they can have many advantages.
Let’s explore each fuel type further to help you decide which is better suited for your circumstances.
New gas boiler cost
A gas boiler burns natural gas (from the national grid) to provide water for your central heating and hot water outlets. Gas-fuelled boilers are the most common in the UK because most homes are connected to the grid - making installation quick and easy. In addition, gas has historically always been the cheapest fuel option.
But how much does a new gas boiler cost? Current market prices estimate a new gas boiler costs between £600 and £3,300. However, in cases of complex fittings, the installation prices of the best gas boilers could add up to £2,000 to this total.
| New gas boiler cost | |||
|---|---|---|---|
| Household size | New gas boiler cost | Estimated installation cost | Total |
| 1 - 2 bedroom | £600 - £1,700 | £1,000 - £2,000 | £1,600 - £3,700 |
| 3 - 4 bedroom | £700 - £2,900 | £1,700 - £4,900 | |
| 4+ bedroom | £800 - £3,300 | £1,800 - £5,300 | |
When it comes to running costs, gas boilers are the cheapest available since gas prices are currently 6.34p/kWh. Annual running costs, therefore, will likely fall around £729.10.
| Boiler type | Pence per kWh | Annual running cost |
|---|---|---|
| Gas | 6.34p | £729.10 |
If you’re unsure of which boiler type you need, and how expensive the installation might be, we recommend comparing quotes from several installers. However, tracking down qualified installers you can trust can be a stressful process. Taking hours of time to read reviews and submit quote forms.
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Just fill in our 30-second form, and we’ll do the rest. Click the button below to get started.
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New oil boiler cost
An oil boiler operates by burning a special type of heating oil (such as kerosene) to provide heating for the house. Oil boilers are very similar to gas boilers in the way they function. However, unlike gas (which is connected directly to the home through pipes), oil must be stored in large tanks (usually buried in the garden), which need to be refilled.
This process makes them the most popular heating alternative for homes that aren’t connected to the gas network. Oil has also typically always been comparable in terms of fuel cost to gas (with only a 2-3 pence difference per unit), making oil a popular first choice for these rural homes.
Oil boiler prices start at £1,3000 and can reach as high as £4,000. The price depends on the unit size, manufacturer, and installation costs. In total, new oil boiler replacement costs, including installation, could fall between £2,300 and £6,000.
| New oil boiler cost | |||
|---|---|---|---|
| Household size | New oil boiler cost | Estimated installation cost | Total |
| 1 - 2 bedroom | £1,300 - £1,900 | £1,000 - £2,000 | £2,300 - £3,900 |
| 3 - 4 bedroom | £1,400 - £3,000 | £2,400 - £5,000 | |
| 4+ bedroom | £1,500 - £4,000 | 2,500 - £6,000 | |
Oil-fuelled heating currently costs 6.8p/kWh, making it slightly more expensive than gas. Per year, this equates to £782 in running costs.
| Boiler type | Pence per kWh | Annual running cost |
|---|---|---|
| Oil | 6.8p | £782.00 |
New electric boiler cost
An electric boiler uses the mains electrical supply to provide heating and domestic hot water. You can opt for an electric boiler whether you need a combi, system, or conventional model. However, compared to gas and oil brands, the manufacturer options are still quite limited in this area which can restrict your choice.
The price of an electric boiler can range from £600 to £3,000 depending on the brand, boiler size, and complexity of the installation. Moreover, installation costs will likely fall between £1,000 to £2,000 depending on the location of your home and heating requirements.
| New oil boiler cost | |||
|---|---|---|---|
| Household size | New electric boiler cost | Estimated installation cost | Total |
| 1 - 2 bedroom | £600 - £1,900 | £1,000 - £2,000 | £1,600 - £3,900 |
| 3 - 4 bedroom | £1,400 - £3,000 | £2,400 - £5,000 | |
A major downside to electric heating is that electricity currently costs 24.86p/kWh, making it four times more expensive than gas. In annual running costs, you can expect to pay around £2,858.
| Boiler type | Pence per kWh | Annual running cost |
|---|---|---|
| Electric | 24.86p | £2,858.90 |
All figures are estimates only and do not include additional standing charges. Based on the annual energy usage of a medium-sized UK home (11,500kWh), according to Ofgem’s TDCVs and current price cap. (Jan. 2025)
Electric boilers do, however, have a near 100% efficiency level, as every unit of energy they consume can be turned into heat (compared to gas, which is around 94%, for example).
Finding the right boiler can be tough, but an efficient one saves you money. Comparing local prices and seeking expert advice helps, but searching for trusted installers can be overwhelming and take hours out of your time.
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New boiler prices per manufacturer in the UK
Boiler prices, as we've seen, can vary for many reasons – whether it's boiler type or choice of fuel. Another key factor that will impact your final total is the brand of boiler you choose. While your installer is likely to recommend the best boilers for you (based on their experiences, boiler cost and performance), it's good to know a little about your choices.
In the table below, we've listed the best boiler manufacturers with some typical market prices for each of their boiler types. This should give you a good idea of which brands are likely to cost the most.
| New boiler prices per manufacturer | |||
|---|---|---|---|
| Manufacturer | Combi boiler price range | System boiler price range | Conventional boiler price range |
| Worcester Bosch | £600 – £3,800 | £1,150 – £3,400 | £600 – £3,500 |
| Vaillant | £900 – £2,300 | £1,150 – £1,900 | £990 – £2,000 |
| Viessmann | £1,050 – £2,200 | £1,050 – £2,000 | £1,170 – £1,700 |
| Ideal | £650 – £1,960 | £1,050 – £1,800 | £900 – £1,600 |
| Baxi | £600 – £1,500 | £900 – £1,500 | £900 – £1,550 |
All prices are estimates only.
It might seem odd that there are some large price differences between brands. For example, you can find combi boilers for as little as £600 or almost £4,000. Keep in mind that these prices include all fuel types - but there are other good reasons for such price variation.Most manufacturers will offer a level of warranty cover or guarantee with their products - the longer the warranty, the more you are likely to pay. In addition, things like stainless steel parts or free system filters are often added perks you will see reflected in the cost.Brand reputation is also a big factor, Worcester Bosch and Baxi are among the most well-recognised in the UK. Both have received numerous awards for ‘best boiler’ brands and ‘Which?’ recommendations. They are also likely to be recommended by your installer for their quick installation and easy repair access.Labour cost of installing a new boiler
One of the largest factors to consider when getting a replacement boiler is the installation costs. Our research shows us that installation fees can add £1,000 - £2,000 on top of the cost of your boiler - which is definitely not something you want to overlook!
Labour costs can be from £300 - £500 per day per installer, depending on the provider you use. These rates can quickly add up if you require a complex or lengthy boiler replacement - for example, you want to remove an old conventional boiler system to upgrade to a combi. There are many parts to remove, and potentially replace, which can add time to the overall job.
You should also account for additional services and parts that your system might require. Some examples include:</spa
| Manufacturer | Combi boiler price range |
|---|---|
| New hot water cylinder | £300 - £1,300 |
| System power flush | £450 - £800 |
| Magnetic filter | £100 - £300 |
| New boiler flue pipe | £300 - £600 |
| Wifi heating controller | £150 - £300 |
If an installer deems it necessary to upgrade or clean your system, these costs should be agreed upon with you in advance. However, it’s worth budgeting for any unforeseen concerns that could arise during the installation (particularly if you have a very outdated system).
How much do radiators cost and should you replace them?
Radiators usually last between 15 - 20 years, however, modern radiators are up to 50% more efficient than older models, meaning it could reduce your energy bills if you update them.
If your radiators are over 15 years old and take a long time to heat up, or you notice any corrosion, rust, or leaks - it’s time to upgrade! Doing this at the same time as a boiler replacement can help enhance the entire performance of your heating system.
Here are some estimated prices for radiator removal and fittings:
| Work type | Estimated price |
|---|---|
| Removal and replacement (per unit) | £80 – £200 |
| Relocate a radiator | £80 – £275 |
| Removing a radiator | £40 – £150 |
| Labour cost | £50 – £150 |
Please bear in mind that these costs are only estimates, and you should seek the advice of a professional to get a more precise quote.
How much does boiler conversion cost?
The cheapest option when it comes to boiler installations is to choose a like-for-like replacement. However, in some circumstances, you might want to convert your boiler to a new type. To help you get an idea of the costs involved, we’ve listed some prices below for typical conversions:
| Boiler conversion costs | ||
|---|---|---|
| From | To | Estimated cost |
| Conventional | Combi | £1,600 – £6,000 |
| Conventional | System | £1,600 – £6,000 |
| System | Combi | £1,600 – £5,500 |
| Combi | System | £1,600 – £6,500 |
If you have a specific requirement, for example, you want to relocate your boiler or switch to a different fuel, there may be many additional steps involved in your installation - such as removing tanks or fitting new pipework. These can all add time and parts to your job, meaning higher costs.
How much does moving a boiler cost?
The typical cost to move a boiler ranges from £500 to £1,000, with an average cost of around £750.
Some key factors that will impact the cost of moving a boiler include:
- Type of boiler: Combi boilers are generally cheaper to move, while system and conventional boilers can cost more due to additional components like hot water cylinders and cold water tanks.
- Distance and location: Moving a boiler within the same room is less expensive than relocating it to another part of the house, as this requires more pipework and possibly new gas connections.
- Materials and labour: Costs may include new pipework, flue extensions, magnetic filters, and labour charges.
Can government grants reduce new boiler costs?
There are other ways to save money on a new heating system, though, such as through government grants like the Boiler Upgrade Scheme (BUS) or the ECO4. Take a closer look below.
| New boiler grants | |||
|---|---|---|---|
| Boiler grant | Run time | Potential savings | Eligibility |
| Boiler Upgrade Scheme | Until 2028 | £5,000 off the cost of a new biomass boiler | Homeowners in England and Wales |
| ECO4 | April 1st 2022 - March 2026 | Up to 100% new boiler cover | Qualifying low-income households |
You may receive funding of up to £5,000 through the BUS to support the installation of a biomass boiler.
You’re eligible if you own the property and are replacing a fossil fuel heating system. Prior energy efficiency funding, like insulation, does not affect eligibility.
To apply for this boiler grant, you must have your new boiler installed by an MCS-certified installer. They will confirm your eligibility and agree on a quote for your project, from which the grant is then deducted.
The ECO4 scheme also enables those on low incomes (who meet the right criteria) to access free energy efficiency upgrades to their homes via local authorities or directly from large energy suppliers. This can include a free boiler replacement for pensioners, or boiler repairs.
To qualify, your home must need energy upgrades, and have a household income under £31,000. Eligibility includes benefit recipients or low-income households under ECO4 LA Flex.
To apply for ECO4, contact one of the participating energy supply companies. They will assess your home and confirm whether you are eligible.
To find out more about who qualifies for a boiler grant, read our guides or visit the official government and Ofgem websites.
Can you get boilers on finance?
Financing a new boiler in the UK offers several options to manage the upfront costs:
- 0% Interest-free finance: Some providers offer interest-free credit, allowing you to spread the cost over a set period without additional interest charges. For example, you might pay £150 per month over 12 months for a £1,800 boiler.
- Low-interest finance plans: These plans allow you to spread payments over longer periods, such as 3 to 10 years, with interest rates typically ranging from 4% to 10%. For instance, a £1,800 boiler over 5 years at a 5% interest rate would result in monthly payments of approximately £34.
- Buy now, pay later: This option lets you defer payments for a specified period, often 6 to 12 months. After the deferral, you can either pay the full amount interest-free or opt for a repayment plan with interest.
Could a new boiler save you money?
If you live in a detached house, upgrading from an old, inefficient G-rated boiler to a modern A-rated model could save you £490 per year on heating costs!
Even if your current boiler is F-rated, you're still losing £340 annually compared to an efficient system.
Especially now that energy prices are rising, now is the perfect time to switch and start saving.
For a smooth boiler replacement, consult a Gas Safe or OFTEC-registered installer. Getting multiple quotes from local installers can help you find the best deal, as they often charge less than national companies.
Instead of spending hours searching and comparing, fill in our quick 30-second form. We'll connect you with up to 3 trusted local installers who offer free quotes, saving you time and money!
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- Quotes from local engineers
- Get quotes today, installed tomorrow
- Finance options available
- Save up to £500 on installation
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Frequently Asked Questions
How much is a new boiler on average in the UK?
The average cost of a new boiler in the UK is usually between £600 and £4,000. This is the cost for a new standalone boiler, but prices can go up to £6,000 with the installation costs included.
How much does replacing a boiler cost?
Replacing your boiler with a new one costs between £1,600 and £6,000 on average. The final cost will depend on your local installer’s labour rates, the complexity of the job, and how many hours it takes.
Is it worth buying a new gas boiler?
It is worth getting a new gas boiler if your boiler is over 10 years old. This is because older boilers aren’t as efficient as newer ones, which costs you more in heating bills. If your boiler is also regularly breaking down or you notice any weird smells or noises, these are also signs that you should call a heating engineer and possibly get a new boiler.
Is it cheaper to get a new boiler?
Yes and no. In case your existing boiler is old and inefficient, getting a new boiler will be cheaper than maintaining an older one. Yet, if your boiler is comparably new, repairing and maintaining it is a better option to save money.
What are the running costs of a boiler?
A boiler’s running costs largely depend on its type, fuel source, and efficiency. For a new gas combi boiler, annual running costs can be around £800, but this will fluctuate depending on the current price of gas.