How much is a new boiler?
Combi Boiler Cost
System Boiler Replacement Cost
Conventional/Regular Boiler Cost
Electric Boiler Costs
Oil Boiler Costs
Cost of replacing a conventional boiler with a combi
Boiler conversion costs
Factors that affect the cost of a boiler replacement
How much will a new boiler save you?
Boiler Costs by Manufacturer/Boiler Brand
Are there any Government Grants for new boilers?

Finding the actual cost of a new boiler is incredibly confusing and anger-inducing, like struggling to remove a spider web from your face.

Why do boiler installations range from worryingly cheap three-figure deals to mortgage-worthy sums from the big energy companies?

Here’s an important tip: You don’t have to buy your boiler from your gas or energy provider. With our Trustpilot score averaging 4.8—higher than theirs—and recognition as a Which? Trusted Trader, choosing an independent provider like us is often a smarter, more cost-effective choice.

Key Points:

The average cost for a new boiler installation is between £2,500 and £3,500.
The final cost of a new boiler installation depends on several factors, including your location in the UK, the type of boiler, and the model or brand you choose.
If you meet eligibility criteria, e.g., receiving certain benefits, you could get a new boiler subsidised via the ECO4 scheme.
A new boiler could save you as much as £385 a year (when upgrading a G-rated boiler with an A-rated boiler).
Ultimately, the accurate cost of a boiler installation depends on various factors specific to your situation.
To get an accurate quote and view the latest prices, obtain your custom quote in seconds here.

How much is a new boiler?

Type of Boiler/Fuel Source	Cost Excluding Installation	Cost Including Installation	Average Cost Including Installation
Combi Swap	£600 - £2,000	£1,500 - £4,500	£3,000
System Boiler	£500 - £2,500	£1,700 - £5,000	£3,300
Conventional Boiler	£600 - £3,500	£1,700 - £4,500	£3,000
Oil Boiler	£1,000 – £3,500	£2,500 – £5,500	£4,000
Electric Boiler	£600 - £2,500	£1,700 - £4,500	£2,500
Biomass Boiler	£7,000 - £15,000	£10,000 - £18,000	£15,000

Table data: last updated October 2024.

Factors Affecting New Boiler Costs

The cost of a boiler replacement depends on a variety of factors, these include:

However, a straightforward combi swap is the most popular and typically the least expensive.

Book before 3 pm and you could get your new boiler installed as quick as tomorrow. Check the latest boiler prices here.

We will now explore some of the most common boiler installation cost scenarios to provide you with a more realistic idea of what you can expect to pay...

Boiler Installation Cost Scenarios

Let's start with the UK's most common type of boiler replacement - the gas combi boiler:

Combi Boiler Cost

Boiler Type	Price range (excluding installation)	Estimated installation price
Combi	£600 – £2,000	£1,500 – £4,500

A new combi boiler costs anywhere from £1,500, all the way up to £4,500, including installation, depending on the type of boiler you'd like, its warranty length, how complex the required installation is, and what the labour costs are in the area which you live.

You can check the latest prices using our calculator.

Premium boiler replacement cost = Premium prices.

Complex boiler installation = Complex new boiler installation costs.

London boiler costs = Bloody expensive.

If it's a straightforward job, you should be looking towards the lower end of the scale. If your job is crazily complicated, expect the worst. Most end up with a new boiler cost somewhere in the middle.

Prefer video? Check out our YouTube video on the costs involved in a new boiler installation below:

What is a combi boiler, anyway?

A combi boiler is simply a ‘combination boiler’ - it controls both your heating and hot water, delivering them both instantly on-demand and doesn’t require a hot water cylinder to be heated prior.

They are far more efficient than immersion heaters, so if you have one, it's definitely worth considering an upgrade.

Combi boilers are the home heating dream that the human race has been striving towards since the discovery of fire.

Imagine if Usain Bolt was your postman, but he also did your bins. A combi boiler is like that... basically.

Pros & Cons of Combi Boilers

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System Boiler Replacement Cost

Boiler Type	Price range (exc. installation)	Installation price
System	£500 – £2,500	£1,700 – £5,000

A new system boiler replacement cost can range anywhere from £1,700, all the way up to £5,000.

Again, the final cost can be affected by a number of factors including but not limited to; the boiler manufacturer (and warranty length), required controls, additional pumps/valves and the general complexity of the job.

Want a new system or regular boiler with professional installation as quick as tomorrow? Get your free quote today.

Unlike combi boilers, system boilers require a hot water cylinder in order to function. The new boiler costs above are for the installation of the boiler only and do not include any costs for new/replacement cylinders.

Interested in paying for your boiler monthly? Check our boilers on finance guide, for the full run down.

What actually is a system boiler?

From a purchasing point of view, all you’ll need to know is that they aren’t combi boilers, they’ll have a separate water cylinder (usually in an airing cupboard) and/or water tank (often in your loft) and they don’t provide instant hot water on demand.

If you live in a large home (high hot water demand), with multiple bathrooms, then a system/regular boiler is perfect for you. Check the latest system boiler prices here.

Pros & Cons of System Boilers

Conventional/Regular Boiler Cost

Boiler Type	Price range (excl. installation)	Est. installation price
Regular	£600 – £3,500	£1,700 – £4,500

Looking for a new conventional boiler? You can expect to pay between £1,700 and £4,500, including gas-safe installation.

As always, the final price will depend on the size and brand of conventional boiler you choose, as well as the complexity of the job.

What is a Regular/Conventional Boiler?

A conventional boiler, also referred to as a regular or heat-only boiler is one of the more traditional types of domestic boiler that are still commonly installed in larger homes.

A heat-only or regular boiler has three main components – the boiler itself, a separate hot water storage cylinder and a cold water storage tank.

The boiler supplies hot water to both the central heating and storage cylinder, so can provide both hot water and heating water.

Regular boilers are a good choice for properties with multiple bathrooms and high hot water demands and are ideal for areas that suffer from low water pressure.

In addition, they are a good choice for those with older/traditional heating systems that cannot tolerate the high pressure of a system or combi boiler.

Pros & Cons of Regular Boilers

Electric Boiler Costs

Boiler Type	Price range (excl. installation)	Est. installation price
Electric Combi	£600 – £2,500	£1,700 – £4,500

An electric boiler can be either a combi, regular or system boiler, but instead of being powered by natural gas, it is powered by electricity, typically from the National Grid, much like most other household appliances.

Interested in an electric boiler? On average, an electric boiler will cost somewhere between £600 and £2,500 depending on the model, size and type of electric boiler e.g. combi or system.

For an electric boiler plus installation, you are looking to pay around £2,500 on average in the UK.

Oil Boiler Costs

Oil boilers work in a very similar way to gas boilers, but instead of gas, they utilise oil or diesel in the combustion process, which in turn heats the water.

For this reason, oil boilers are used widely by households not connected to the gas grid, for example, homes in rural and remote locations.

The price for a new oil boiler starts at around £1,000 but can go as high as around £3,500 for a large boiler from a premium brand and in the case of more complex installations, the boiler and fitted cost can be as high as £5,500.

Boiler Type	Price range (excl. installation)	Est. installation price
Oil	£1,000 – £3,500	£2,500 – £5,500

Cost of replacing a conventional boiler with a combi

Type	Price range (excl. installation)	Est. installation price
Regular to combi conversion	£600 – £2,000	£1,500 – £4,500

Upgrading a traditional boiler to a combi boiler is a bucket list regular for most UK homeowners, sitting seven places above seeing the Pyramids and just one below breaking free from lifelong, crippling debt.

Conversions can be complex beasts, and they come with costs you'd associate with a complex beast.

Please note: Ultimately an accurate boiler installation cost depends on a variety of factors personal to your situation.

Find out what boiler you need along with costs (takes 60 seconds) »

But exactly how much extra will you be paying?

Included in the cost of a boiler conversion, is the full removal of your old boiler & water cylinder, newly upgraded pipework fed to the existing or new location of the incoming combi boiler and of course, the new combi boiler itself.

...and that’s a simplified version.

It can be a big job, requiring two days of work and engineers so, in tune with their tools, they can make a crowbar dance.

Putting you out of your misery early, you’ll roughly be looking at at additional £800 - £1200 worth of expense on top the standard boiler swap cost.

Boiler conversion costs

These fixed prices assume a straightforward conversion and the costs include all of the above, plus upgraded heating controls, a full chemical cleanse of your existing boiler system, boiler filter and registration.

Do note that other, much more expensive quotes are available elsewhere. Try your energy provider if you fancy a laugh.

When converting your regular boiler into a combi boiler, do remember that any boiler manufacturer can be fitted so long as it’s the correct size and powerful enough for your hot water demands consider referring to our best combi boiler article to gain more insight than you ever thought possible.

Want to know which boiler power is suitable for your home? Check out our "what size boiler do I need" guide.

How much does a back boiler to combi conversion cost?

Boiler Type	Price range (excl. installation)	Est. installation price
Back boiler conversion	£600 – £2,000	£3,500 – £5,000

You can scan over a more comprehensive back boiler description in this article if you’ve run out of paint to watch dry…

…But a broken back-boiler is an old dog that needs to be put down.

They can no longer be repaired in accordance with modern regulations and you will need to convert your system - most likely to a modern combi boiler.

Heatable applies a transparent, and fixed cost of £395.00 on top of our standard conversion costs. This can get much steeper when buying from other national companies so make sure you don’t settle for your first quote.

The work involved in the conversion of a back-boiler is very much similar to a standard conversion in that it includes the removal of your entire existing system and introduction of the new combi and required combi pipework, however, it’s the awkward location of the back boiler behind your fireplace that incurs the sometimes significant extra cost.

Many installers and installation companies hate carrying out this work and will therefore simply price themselves so high they can just about bear it or high enough to discourage customers.

Want to have your boiler moved to a different location? Check out our "cost of moving boiler" guide.

If your radiator is cold at the bottom, it's likely a build-up of sludge, but in some cases, it may be a sign of a faulty heat exchanger or a faulty boiler valve, in which case getting your new boiler replaced may be appropriate, check out the Worcester Bosch Greenstar 30i, which you can purchase through us.

Want the exact price of a new boiler? Use our boiler quote calculator.

Case study: Cost to convert a Baxi Bermuda back boiler to a combi boiler

Converting from a Baxi Bermuda - or any brand of back-boiler - can appear costly upfront but the rewards are there to be reaped for years to come.

Replacing your old back boiler will:

Significantly reduce your energy costs
Slash your carbon footprint
Provide you with instant hot water on demand
Save your marriage
Improve the safety of your home
Increase the resale value of your property

Is your home doomed with a back boiler that you can't afford to convert? Sell it (your whole house that is).

If you live in an average-sized home, see our guide on choosing the best boiler for a 3-bedroom house.

Factors that affect the cost of a boiler replacement

The raw bones of the pricing structure may well be the cost of the boiler + labour cost.

But that’s an oversimplification.

Here are the top factors to take into account when calculating your new boiler costs (...there's a lot!):

#1 - How much does a new boiler cost? £600 → £2000

Probably the most pivotal aspect of any installation – the actual boiler. Boiler replacement costs for quality boilers will be in the high hundreds/early thousands and vary depending on their quality, model, kW size, and brand.

Typical boiler replacement cost:
£600 → £2000

#2 - Boiler installation labour cost: £600 → £1500

The cost of a boiler installation will depend on the amount of labour required. This can vary based on your location and the business you use, how long it takes to install the boiler and the number of engineers required.

On average the cost to install a new boiler will be between £600 and £1,500, which depends on the exact type of installation.

For example, a combi swap, taking around a day to complete is much quicker than a back boiler conversion, which takes around 2 days and may require more than one engineer to attend.

The cost of boiler installation is typically included in the fixed price quote, so if you choose to purchase your boiler via Heatable you don’t have to worry about juggling different costs and calculating a final figure.

Labour cost (swap):
£600 → £800

Labour cost (conversion):
£1000 → £1500

#3 - Vertical flue cost: £300 → £600

A boiler flue, simply put is the large pipe that leads from the boiler to the outside of your home – ensuring condensation and flue gases are pumped outside and not into your own face – vital.

Most of the time, the flue will leave your property horizontally incurring no extra costs but flues that leave vertically through your roof require much more work and therefore incur more costs. It can be just plain bad luck.

Typical vertical flue cost:
£300 → £600

#4 - Plume kit cost: £90 → £130

A plume kit is essentially an extension kit that attaches to your boiler’s flue. The plume kit is required in instances where your boiler's flue is too close for comfort to a window, door, neighbouring property, or your wife and is required by law in order to comply with gas-safe regulations.

Failure to include a plume kit could lead to London's standard air purity levels. Unless you already live in London, in which case, boiler fumes may seem a welcome breath of fresh air.

Typical plume kit cost:
£90 → £130

#5 - Main gas pipe upgrade cost: £250 → £400

Many older heating systems are built using gas piping of a certain width (often 15mm). To meet modern regulations, they need to be upgraded to 22mm in most cases which can sometimes incur additional costs.

In some instances, older pipes will also be made from lead, cheddar or the bones of early settlers and these will need to be replaced with copper piping.

Heatable never charge for upgraded pipework, whereas most installation companies will add this to your bill with unnerving pleasure and an evil laugh.

Be wary of rogue traders who don’t plan for upgraded pipework – their boiler replacement costs and installation fees will be more illegal than the contents of a duffel bag in the back of their uninsured white van.

Related reading:

Typical gas upgrade cost:
£250 → £400

Our gas upgrade cost:
£0

#6 - Cost to relocate boiler

Moving the location of your boiler is costly and will require a lot of physical labour, additional pipework, emotional robustness, and various general new fixtures and fittings.

Unless moving your boiler is integral to every hope and dream you have held since you were a child, do try to avoid it.

Want to save money and energy on your heating bills? If so, you should consider installing one of the best smart thermostats.

#7 - Upgraded heating control costs: £100 → £300

The days of having a painstaking, back-breaking walk to your boiler to switch it on are almost behind us as a species and most new boiler installations will include some form of upgraded controller.

Depending on the type and brand of the controller, it will add varying figures to your new boiler cost.

Heating controls cost:
£100 → £300

Our heating controls cost:
£0** - that's free!

**Smart controls are not included as standard but can be purchased at an additional cost.

#8 - Upgraded warranty costs

Extended warranties, particularly 10-year warranties in most cases are only able to be offered by trusted partners of manufacturers.

They can sometimes rely upon the fitting of additional approved equipment like magnetic boiler filters and will often incur additional costs to that installer, but a longer warranty is certainly a cost worth incurring.

Think you've found a bargain? Check the warranty length has a longer expiry date than the last lot of milk you bought.

#9 - Magnetic boiler filter cost: £100 → £200

Filters are installed inline on the pipework and help to protect your boiler. They use powerful magnets that trap small particles of dirt and metal, stopping them from going into the boiler itself and causing unnecessary damage and boiler leaks.

A quality boiler installer will always build the cost of installing a filter into your quote. We include them, but we don't charge a penny more and fit them as standard throughout the UK.

Magnetic boiler filter cost:
£100 → £200

Our magnetic filter cost:
£Zero

#10 - Chemical flush: £100 → £150

Flushes help to clear out existing sludge from your heating system. If you don't clear it, sludge will stop the hot heating water from flowing around your radiators efficiently. Not good. You'll need a deep clean if your radiators are cold at the bottom.

There are various types of 'flushes' available. A hot, chemical flush is the most common and pretty standard. But, you can pay upwards of £500 for a 'Powerflush'. Be careful with those, though. If you start forcing high-pressure water through an old heating system, it can often do more damage than good.

Did you know our boiler installation cost calculator only takes 60 seconds to complete? Using a series of multiple-choice questions, it can provide you with a fixed price on a range of budget-friendly boilers.

Learn all about the best combi boilers in our what is a combi boiler guide.

Chemical flush cost:
£100 → £150

Heatable's flush cost:
£0 - Free again.

#11 - Radiator Costs

When installing a new boiler, it's often a good idea to look at your heating system overall, which includes your radiators.

After years of use, it's normal for radiators to experience wear and tear, or if they are simply old models they may be inefficient and have a poor performance in comparison to the latest offerings.

The exact price of new radiators depends on a variety of factors including size, material, design and how many you require.

The final cost of a new boiler replacement

As you can see there are a variety of factors that can impact the final boiler installation cost.

The above list is to be used as a guide only. To get a fixed, accurate price for your boiler replacement installation, go here.

How much will a new boiler save you?

Old boilers are inefficient and for every £10 you’re spending on running them, you could be throwing up to £4 of that out of the window.

This creates a huge mound of pound coins on your patio that poses a risk to the local eco system.

New boilers – particularly combi boilers – are incredibly efficient compared to their older counterparts and come packed with intuitive technology to work smarter for your home's heating needs.

This dramatically reduces the amount of fuel used, whether that be Gas, Oil or LPG.

Old Boiler Rating:	Bungalow	Detached House	Flat (Mid-Floor)	Semi-Detached House	Mid Terrace House
G (<70% efficient)	£345	£640	£150	£385	£320
F (70-74% efficient)	£245	£460	£100	£275	£225
E (74-78% efficient)	£195	£370	£80	£220	£180
D (78-82% efficient)	£150	£295	£60	£170	£140

Feast your eyes on the above typical energy savings courtesy of the Energy Saving Trust.

They’re the most trustworthy name in the UK energy savings data collection game – an industry notorious for its untrustworthy, shark-filled business waters.

Boiler Costs by Manufacturer/Boiler Brand

Typically, most boiler brands have a boiler range that includes entry-level, mid-range and premium boiler models, which increase in price, respectively.

However, there is some variation between the different boiler manufacturers, which is dictated by things like brand reputation, warranty length and technical differences e.g. some boilers use plastic parts, while other brands only use brass.

With that in mind, here are the new boiler costs you can expect for some of the most popular boiler brands available in the UK:

Boiler Brand:	Combi Boiler Price Range	System Boiler Price Range	Conventional Boiler Price Range
Worcester Bosch	£1,500 - £3,500	£1,200 - £2,600	£1,200 - £2,600
Vaillant	£1,500 - £3,700	£1,200 - £2,200	£1,200 - £2,200
Viessmann	£1,500- £3,500	£2,000 - £2,500	£2,000 - £2,500
Ideal	£1,300 - £2,500	£1,300 - £2,500	£1,300 - £2,500
Alpha	£1,000 - £2,400	£1,000 - £2,400	£1,000 - £2,400
Baxi	£1,300 - £2,500	£1,300 - £2,500	£1,300 - £2,500

Are there any Government Grants for new boilers?

At present, there are two government grants available to assist with new boiler costs, but they typically do not cover the entire cost and you must meet specific eligibility criteria.

These are the Energy Company Obligation (ECO) Scheme and the Boiler Replacement Scheme (Operating in Northern Ireland Only).

Energy Company Obligation (ECO)4 Scheme

As you might guess, this is the fourth in a series of boiler grants from the UK government with this latest scheme set to cover 2022 to 2026.

The scheme’s primary goals are:

Improve the energy efficiency of UK homes
Reduce fuel poverty
Make energy more affordable

But what does the ECO4 scheme offer exactly?

The ECO4 aims to upgrade the energy efficiency of nearly half a million UK homes.

As for the requirements, you must be receiving a government benefit in order to be eligible for the ECO4 scheme. These are as follows:

Income-based jobseekers allowance or JSA
Income Related Employment & Support Allowance (ESA)
Income Support (IS)
Pension Credit Guarantee
Working Tax Credit (WTC)
Child Tax Credits (CTC)
Universal Credit (UC)
Housing Benefit
Pension Credit Savings

Boiler Replacement Scheme, Northern Ireland

The second scene that can help with new boiler costs is called the Boiler Replacement Scheme which is operational in Northern Ireland only.

Like the ECO scheme, there are eligibility criteria and eligible households can receive up to £1,000 towards the cost of a new boiler.

Related reading:

Get A New Boiler Quote Today

If you’re aiming to get the best deal on a new boiler, consider getting a quote from us, here’s why:

Gas Safe installation within 24 hours.
Thousands of satisfied customers with an average score of 4.9 on Trustpilot, surpassing the market leader.
Which? Trusted Trader: Heatable is proudly recognised as a Which? Trusted Trader.
Price match guarantee: We will match any like-for-like cheaper quote.
Flexible payment options, including interest-free finance.
Up to 12-year guarantee on selected boilers.
Fixed price guarantee: No hidden costs.
Save your quote and decide later.
Get an instant fixed price on a new boiler, here.

To learn more about boilers, visit our advice section, check out our YouTube channel, or read customer testimonials here.

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