![How much does it cost to replace a boiler? [March 2025]](https://d21dfqs8hl0txa.cloudfront.net/cost-guides/main/how-much-does-boiler-replacment-cost.png)
The short answer
- A boiler replacement should cost on average £1,000 - £4,500 (inc. VAT)
- In London, a replacement usually costs £1,500 - £4,500 (inc. VAT)
- Outside of London, a boiler replacement normally costs £1,000 - £4,000 (inc. VAT)
- You should consider replacing your boiler after 10-15 years
- There are usually clear signs when it's time to replace a boiler before the 10 year mark
Looking for a quote for your boiler replacement? Click here to get your quote online
Contents
- How much does the labour for replacing a boiler cost?
- How much does the actual boiler cost?
- Which other factors impact the cost of boiler replacement?
- What's the difference between a combi boiler, a heat-only boiler and a system boiler?
- How often should you replace a boiler?
- What are the signs you should replace a boiler?
- What’s included in a boiler replacement?
- Where can I find an engineer to replace my boiler?
- Sources
How much does the labour for replacing a boiler cost?
The labour for replacing a boiler typically costs between £500 - £1,200 including VAT. The process usually takes 1-2 days, depending on whether it's a like-for-like swap or a switch to a different type of boiler.
The total cost will depend on a few different factors, but the type of fuel the boiler uses and whether it's a system, combi (combination) or a heat-only boiler will most likely be the biggest factors.
Here’s a breakdown of how much you can expect to per for labour only, when replacing your boiler - whether you're inside or outside of London.
| Type of boiler | Price range (outside London) | Price range (in London) |
|---|---|---|
| Electric (combi boiler) | £500 - £800 (inc. VAT) | £700 - £1,000 (inc. VAT) |
| Electric (system boiler) | £700 - £900 (inc. VAT) | £900 - £1,200 (inc. VAT) |
| Electric (heat only) | £500 - £800 (inc. VAT) | £600 - £1,000 (inc. VAT) |
| Gas (combi boiler) | £600 - £900 (inc. VAT) | £600 - £1,000 (inc. VAT) |
| Gas (system boiler) | £700 - £900 (inc. VAT) | £900 - £1,200 (inc. VAT) |
| Gas (heat only boiler) | £500 - £800 (inc. VAT) | £600 - £1,000 (inc. VAT) |
| Oil boiler | £600 - £1,000 (inc. VAT) | £800- £1,200 (inc. VAT) |
These prices are ranges based on industry experience. Get a quote to replace your boiler here.
How much does the actual boiler cost?
There are a few different types of boilers available, including system, combi (combination), 'heat only' (also known as conventional) and oil.
Your engineer will be able to recommend the best boiler for your home based on your households needs. Larger households will generally need a more powerful boiler to handle the higher water demand. While you can supply the boiler unit yourself, it's typically more convenient for your engineer to source it locally on your behalf. Keep in mind that your engineer may charge an additional fee to cover the time and effort involved in sourcing the boiler.
Currently, around 78% of UK households rely on gas central heating, meaning they have a gas boiler. [1] However, new homes built from this year will no longer be permitted to install gas boilers, and by 2035, the sale of gas boilers is expected to be banned. [2] So, this is something you may want to consider when choosing which boiler is right for you.
Here's a breakdown of what you can expect to pay for the actual boiler unit only.
| Type of boiler | Unit cost |
|---|---|
| Electric (combi boiler) | £800 - £2,000 (inc. VAT) |
| Electric (system boiler) | £900 - £1,500 (inc. VAT) |
| Electric (heat only) | £500 - £1,200 (inc. VAT) |
| Gas (combi boiler) | £600 - £2,000 (inc. VAT) |
| Gas (system boiler) | £600 - £2,000 (inc. VAT) |
| Gas (heat only boiler) | £500 - £1,500 (inc. VAT) |
| Oil boiler | £2,000 - £3,000 (inc. VAT) |
Which other factors impact the cost of replacing a boiler?
In addition to the type of boiler you're having installed, your location, the timing of your booking, and the company or tradesperson you choose are usually the other biggest factors in determining the cost of a boiler replacement service.
1. Where you live
Rates will vary depending on your location within the UK. Typically, larger cities, especially London, have higher rates, with costs often being around 20% more than in other areas. In these cities, you may also face additional charges, such as parking, clean air, and congestion fees, which are more commonly implemented in urban areas.
On the other hand, if you live in a rural area, engineers may charge extra to cover the additional travel time to reach your property.
2. Whether they're an independent engineer or working for/with a heating company
Independent heating engineers typically charge lower rates compared to larger, more established companies. Some self-employed tradespeople may also operate below the VAT threshold, meaning you could save the additional 20% VAT that would usually be added to your service cost.
While services from larger companies often come at a premium, they can offer certain advantages, such as greater availability of dates and times, as well as a responsive customer service team to assist if anything goes wrong.
3. How busy your local engineers are
The cost of a boiler service can also be influenced by the availability of tradespeople in your local area. You'll usually find that during the winter months, when gas and heating engineers are often busy with emergency repairs, costs may be higher than during the summer.
The time of day or week you book can also affect the price. Rates tend to be higher during unsociable hours, such as early mornings, evenings, weekends, or bank holidays. Also, booking a same-day or next-day appointment typically comes with a premium.
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What's the difference between a combi boiler, a heat-only boiler and a system boiler?
Combi (combination) boilers directly provide both heating and hot water from the boiler itself, which means you can get hot water on demand. They're fairly energy efficent, and typically cheaper to run than other types of boilers. However, their compact design and limited capacity for dealing with high water demands means they're best suits to smaller homes.
System boilers are boilers that have many of their essential components built directly into the unit. They don't need a cold water tank, but they do require a separate hot water cylinder. One downside of system boilers is that hot water needs to be preheated in advance, so you can’t access it instantly on demand. However, they are capable of supplying hot water to multiple outlets at the same time, making them well-suited for medium to large homes.
Heat-only (or regular/conventional) boilers require both separate hot water cylinders and cold water tanks. While the separate tanks allow them to handle higher hot water demands, they do take longer to heat up. They're larger size means that this type of boiler is best suited to larger homes with higher hot water demands.
How often should you replace a boiler?
A boiler is probably good for around 10-15 years, as long as it's serviced regularly. You should get a boiler service once per year to ensure everything keeps ticking along nicely.
Boiler repairs can be expensive, so if you're getting your boiler repaired often at around the 10 year mark, it's usually more cost efficient to just replace the boiler instead.
What are the signs you should replace a boiler?
Even with regular servicing, boilers don't last forever. Over the years, you may start noticing a few signs that it might be time to replace your boiler.
1. Frequent breakdowns
If you're noticing your boiler breaking down more often, it may be time to start thinking about replacing it. Boiler repairs aren't cheap, so it may get to a point where it's more economical in the long run to just replace the whole boiler.
For example, if your gas combi boiler is older than 8 years and the repair costs over £1,000, it's usually more economical to replace it. Likewise, if your gas 'heat only' (or conventional) boiler is more than 4 years old and repair costs exceed £1,000, you should consider a replacement.[3]
2. Unusual sounds & smells
Of course, your boiler will make some noise when used, but any banging or humming sounds could indicate a fault. If you notice a sulfur-like (eggy) smell, this may be a sign of a gas leak. In this case, you should immediately turn off your boiler and contact an emergency gas service for assistance on 0800 111 999.
3. Rising energy bills
If you have an older boiler, it’s likely not as efficient as modern models. In fact, if your boiler is over 10 years old, it may have a G-rating, meaning it’s wasting a fair amount of energy. For comparsion, all new boilers must have a A efficiency rating. So, if you’ve noticed your energy bills increasing, it probably worth upgrading to a newer, more efficient boiler to save on energy costs in the long run.
4. Performance issues
If you're noticing your boiler just isn't working as well as it used to, for example, your hot water temperature is fluctuating or your radiators are taking longer to heat up, it may be time to consider a replacement.
What’s included in a boiler replacement?
The specific tasks involved in a boiler replacement will vary depending on the fuel type and model of your boiler. Replacing a boiler like-for-like, will generally be a much simpler process than installing a completely new type of boiler.
A boiler replacement typically includes some or all of the following:
- Disconnection and removal of the old boiler
- Positioning and securing the new boiler
- Connecting water and gas pipes
- Wiring electrical connections (e.g., thermostats, controls)
- Installing additional components (such as water filters or new expansion tanks)
- Testing gas pressure
- Inspecting safety features (including vents, carbon monoxide detectors, and other safety mechanisms)
- Cleaning the installation area and removing any debris
- Proper disposal of the old boiler
Where can I find an engineer to replace my boiler?
There's plenty of ways to find an engineer for a boiler replacement, whether that's online, through your boiler manufacturer or through a recommendation. However, it's important to bear in mind that a boiler replacement should always be carried about by a qualified engineer.
If you're replacing/installing a gas boiler, the replacement must be completed by an engineer who is Gas Safe Registered to ensure safety and compliance with regulations. Even if you're installing an electric boiler, it best practice to use a Gas Safe Registered engineer too, as most all good heating engineers hold this accreditation. You can search for or check a local Gas Safe engineers credentials through the Gas Safe Register’s online directory.
If you're looking to replace/install an oil boiler, it's highly recommended that you use an engineer credited by the OFTEC 'competent persons scheme'. You can easily check whether an engineer or business is OFTEC registered through their website.
If you're looking to use an established tradesperson company, you can get a quote for a boiler replacement through the Housekeep website. Just click below, and we'll give you an instant price.
Written by Henry Paterson
With years of experience in the industry, Henry is one of Housekeep’s home services specialists. He’s delivered talks at industry events including the Ideal Home Show and regularly features as an industry expert for publications including the Sun, Mail Online, Martha Stewart and many more.
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