How much does a new boiler cost in the UK

1. Combi Boiler Cost

New Combi Boiler Average Cost (Installed): £1,800 - £4,500

Advantages: Space-saving, energy efficient, on-demand hot water.

Combi boilers have long since been the most popular type of boiler in the UK (around 80%) due to the fact they conveniently ‘combine’ both a home’s central heating duties and hot water production into one compact, powerful unit.

The price foe a new combi installed can range due to many varying factors such as size, complexity and labour, however the average cost sits around £1,800 - £4,500 for a boiler suitable for a 3-4 bedroom home.

Best property match: smaller homes to medium homes, flats, properties with only one shower or bath. 

2. System Boiler Cost

New System Boiler Average Cost (Installed): £1,800 - £5,000

Advantages: Powerful, stores hot water, great for larger spaces.

System boilers are perfect for homes with higher hot water demands, such as those with two or more bathrooms. System boilers work with a water cylinder which stores hot water to allow for high pressure service to multiple outlets at the same time.

Best property match: Larger properties or properties with more than one bathroom.

3. Conventional Boiler Cost

New Conventional Average Boiler Cost (Installed): £1,800 - £5,000

Advantages: Suited to large properties, reliable and consistent.

Conventional (heat-only or regular) boilers are very hardworking and a tad more long standing in terms of their design and function. They do however require an external hot water cylinder and cold water storage tank.

Best property match: Big homes with more than one bathroom or lower water pressure.

4. Electric Boiler Cost 

New Electric Boiler Average Cost (Installed): £1,800 - £5,000

Advantages: Very high-efficiency, more environmentally friendly

Electric boilers are a fantastic option for larger homes, especially those without a connection to gas. New electric boilers are not only highly efficient but also considered ‘green’ due to their lack of reliance upon fossil fuels.

Often the cost of an electric boiler may be cheaper than gas due to the fact they do not require a flue or specific pipework. However, it should be noted that electricity is actually more expensive in terms of running costs compared to gas.

Best property match: Properties with no established gas connection, ‘green’ homes.

5. Oil Boiler Cost

New Oil Boiler Average Cost (Installed): £2,200 - £5,000

Advantages: Great for homes that are rural or off-grid

Oil Boilers are an older type of system, strong but most commonly found in rural properties or homes that do not have an established gas connection.

Best property match: Rural or countryside homes within no gas connection.

It can be important to remember that the cost of a new boiler replacement isn’t only the cost of the appliance itself, but also everything that goes into the process to ensure safety and efficient performance.

Boiler costs by brand

The cost of a boiler can vary depending on the brand of the boiler. Some manufactures have outstanding quality of build and remembering the old saying "you get what you pay for".

Check out our full expert guide on the best boiler brands and what they can do to revamp your home’s central heating.

Influencing costs to consider

A quick guide on what common additional costs you may need to account for when it comes to getting a brand new shiny boiler.

1. The boiler

Of course the main fee for boiler installation is that of the actual new boiler unit itself, without labour. New boilers (just for the boiler unit) can often cost into the early thousands, especially for trusted and award-winning models.

Average boiler unit cost: £800 - £2,000

2.  Installation (engineer labour)

The next most vital fee to consider is the cost of the boiler being installed by a Gas Safe heating engineer.

This exact amount of this fee is usually dependent on several factors unique to each boiler installation, such as:

• Region of the property 

• Complexity of the install

• Boiler type and model

• Number of engineers required

• Added work (system or piping replacements)

Some more straightforward installations such as direct like for like swaps are far quicker and less expensive than old system conversions, for example.

Installation costs are always included in any fixed price iHeat new boiler quote, so you don't have to worry.

Average installation costs: £700 - £1,500

3. Flue cost

The flue is the pipe that transports exhaust gases to outside the home, an essential safety feature. Flues can either be vertical (straight up through the roof) or horizontal (sideways through a wall).

Vertical flues often require more intensive labour to fit correctly, and can therefore provide a higher cost.

Average vertical flue cost: £350 - £550

4. Plume kit cost

A plume kit is a component which extends the flue in order to divert the exit fumes in a safe manner, should the flue be deemed too close to features such as windows or gardens. A tad annoying as an additional cost perhaps, but an essential piece of safety equipment.

Average plume kit cost: £80 - £150

5. Gas pipe upgrade cost

If your home has 15mm pipes they’ll need to be upgraded to roomier, and more efficient 22mm ones.

Here at iHeat, we safely swap out all old 15mm piping to new robust 22mm completely FREE, at no extra cost where applicable.

iHeat gas pipe upgrade cost: FREE

6. Boiler relocation costs

The added labour of physically moving a boiler to a new home within the property can bolster fees due to the added complexity of the install. The boiler, as well as pipework must safely be relocated and connected to ensure a smooth transition and continuation of central heating performance.

7.  Carbon monoxide alarm cost

CO (carbon monoxide) alarms are a specialist bit of kit that alerts a homeowner to potentially life threatening hazardous gas leaks.

With every new boiler installation iHeat offers a FREE CO alarm.

iHeat CO alarm cost: FREE

8. Smart thermostat cost

Helpful technology such as wireless thermostats allow a homeowner to easily control or adjust their property’s central heating or hot water production, all at the click of a button.

with every new boiler installation, iHeat offer a FREE wireless thermostat.

iHeat wireless thermostat cost: FREE

9. Extended warranty cost

A boiler warranty is a little extra peace of mind for a homeowner that should a boiler begin to have issues at no fault of their own, within an appropriate time period, the manufacturer agrees to either fix or replace the unit.

Boiler manufacturers often offer extended warranties highlighting their confidence in their boilers performance and longevity.

10. Magnetic boiler filter cost

Magnetic boiler filters trap pesky debris within the system to keep your boiler in the best possible working condition for the longest amount of time possible.

With every iHeat installation you get a FREE magnetic filter to protect your boiler from sludge and debris.

iHeat magnetic boiler filter cost: FREE

11. Chemical flush cost

Chemical flushes are a system cleaning procedure that will remove any unwanted bits and bobs to allow your new boiler to run as best it can.

Chemical flushes are offered as part of every new boiler installation for FREE with iHeat.

iHeat chemical flush cost: FREE

12. Replacement radiator cost

Even after installing a brand new boiler, if your property's radiators are useless, your home still won’t be as toasty as you desire. If this is the case it’s worth replacing the older radiators with new and heat efficient ones.

Average radiator cost (full set): £300 - £400

Government grants and funding available in 2025

If you happen to qualify, the UK government actually runs a grant scheme to help aid with the financial aspects of getting a new and efficient gas boiler installed.

ECO4 scheme

The ECO4 scheme is a government initiative that hopes to improve the UK’s energy efficiency while reducing fuel poverty. The government wants this scheme to be as helpful as possible with plans of upgrading 500,000 boilers by next year.

Qualifying criteria for a reduced cost boiler upgrade can include:

• Universal credit

• Pension credit

• Child tax credit

• Housing Benefit

• Income support

(If you think your home would benefit from a biomass boiler, check out our guide on the Boiler Upgrade Scheme)

How much money could a new boiler save me?

Modern gas boilers are far more energy efficient than older models, meaning by installing a new boiler, you would actually start to save money long term due to the reduced energy bill costs.

How much will you save with an A-rated boiler, you ask? Well, here’s a quick breakdown:

New boiler cost summary

The average new boiler cost in the UK can vary depending on the type of new boiler and the complexity of the installation.

• Combi Boilers - efficient and space-saving, combi boilers are the UK’s most popular boiler with an average cost of £2,500 - £3,500.

• System Boilers - powerful and suited to large properties, new system boilers have an average cost of £2,200 - £3,500.

• Conventional Boilers - reliable and straightforward, ‘heat-only’ boilers have an average cost of £1,800 - £3,200.

• Electric Boilers - environmentally friendly and very efficient, these boilers have an average cost of £1,800 - £3,500.

• Oil Boilers - traditional and robust, oil boilers have an average cost of £2,600 - £5,200.

• Biomass Boilers - the greenest option for eco friendly homes, these boilers have an average cost of £9,000 - £15,000.

New Boiler Quotes with iHeat

We’re an online boiler installation company who pride ourselves on being able to give our customers nationwide stress-free boiler installations.

• Wide range of award winning boilers form only the most trusted brands

• Free online fixed price quotes in  just 60 seconds

• Brand new boilers installed as fast as next day

• Which? Trusted trader accredited

• Partnered with some of the biggest names in the heating industry

Get a quote

References
Energy saving trust - https://energysavingtrust.org.uk/advice/boilers/
Boiler upgrade scheme - https://www.gov.uk/apply-boiler-upgrade-scheme