When your old boiler starts breaking down or your heating bills keep rising, it’s time to consider a replacement. But how much does a new boiler actually cost in the UK?
In this detailed guide, we’ll explain average boiler prices, installation costs, grants, and everything else you need to know before buying. Whether you’re upgrading to a combi boiler or switching to an eco-friendly system, this article will help you plan with confidence.
Average Cost of a New Boiler in the UK
In 2025, the average cost of a new boiler (supply only) ranges from £1,200 to £5,000, depending on the brand, size, and type. When installation is included, most homeowners pay between £2,500 and £4,500.
| Boiler Type | Supply Cost | Installed Cost (Approx.) |
| Combi Boiler | £1,500 – £3,000 | £2,500 – £4,000 |
| System Boiler | £1,600 – £3,500 | £2,800 – £4,500 |
| Conventional Boiler | £1,800 – £3,800 | £3,000 – £5,000 |
| Electric Boiler | £1,200 – £2,800 | £2,200 – £4,000 |
| Biomass Boiler | £6,000 – £10,000 | £8,000 – £12,000 |
These prices include standard installation by a Gas Safe registered engineer and may vary depending on your home’s layout and the boiler brand you choose.
1. Combi Boiler Costs
Combi boilers are the most popular type in UK homes. They provide heating and hot water on demand, without needing a separate tank or cylinder.
Average Cost: £1,500 – £3,000 (supply only)
Installed Cost: £2,500 – £4,000
Pros
- Compact and ideal for smaller homes
- Energy-efficient and quick to install
- Provides instant hot water
Cons
- Not suitable for large homes with multiple bathrooms
Combi boilers are ideal if you’re replacing an older system and want to free up space in your airing cupboard or loft.
2. System Boiler Costs
System boilers use a hot water cylinder but no cold water tank, making them perfect for homes with higher water demand.
Average Cost: £1,600 – £3,500
Installed Cost: £2,800 – £4,500
Pros
- Great for families with multiple bathrooms
- Consistent water pressure
- Compatible with solar heating
Cons
- Requires extra storage space for the cylinder
System boilers are a great choice for medium to large properties where several taps may run at the same time.
3. Conventional (Regular) Boiler Costs
Also known as heat-only or regular boilers, these systems are commonly found in older homes with existing water tanks.
Average Cost: £1,800 – £3,800
Installed Cost: £3,000 – £5,000
Pros
- Excellent for older central heating setups
- Can supply hot water to multiple outlets simultaneously
Cons
- Takes up more space
- Slower to deliver hot water
If your home already has a conventional system and you don’t want to change pipework, replacing like-for-like is often the simplest and cheapest option.
4. Electric Boiler Costs
Electric boilers are becoming increasingly popular, especially in areas without mains gas or for eco-conscious homeowners.
Average Cost: £1,200 – £2,800
Installed Cost: £2,200 – £4,000
Pros
- Compact and quiet operation
- No need for a flue or gas connection
- Easier to install and maintain
Cons - Higher running costs compared to gas boilers
Electric boilers are a good option for flats, small homes, or off-grid properties that use renewable electricity.
5. Biomass Boiler Costs
Biomass boilers use renewable fuels such as wood pellets or logs. They are more sustainable but come with higher upfront costs.
Average Cost: £6,000 – £10,000
Installed Cost: £8,000 – £12,000
Pros
- Renewable and environmentally friendly
- Can reduce carbon emissions significantly
Cons
- Expensive to install
- Requires fuel storage space
While the installation cost is higher, the long-term energy savings and potential government incentives can make biomass boilers a smart investment.
Installation Costs Explained
Boiler installation typically costs between £1,000 and £2,000, depending on the complexity of the job.
What Affects Installation Price
- Type and size of the boiler
- Location of the installation
- Pipework upgrades or rerouting
- Flue and condensate requirements
- Optional extras like smart thermostats
A like-for-like replacement (for example, combi to combi) is usually completed within 4–6 hours. Switching from a traditional system to a combi boiler may take up to 2 days because of additional plumbing work.
If you’re looking for professional Boiler Installation Stoke-on-Trent, hiring a local Gas Safe engineer ensures safe fitting, competitive pricing, and quick service.
Additional Costs to Consider
| Item | Typical Cost |
| Magnetic Filter | £60 – £160 |
| Power Flush | £300 – £600 |
| Smart Thermostat | £150 – £300 |
| Flue Replacement | £100 – £200 |
| Thermostatic Radiator Valves | £30 – £70 each |
A smart thermostat (like Hive or Nest) can help you control heating more efficiently and cut your bills by up to 20% per year.
Key Factors That Affect Boiler Price
- Boiler Type – Combi, system, or conventional boilers vary in complexity and cost.
- Brand Choice – Premium brands like Worcester Bosch, Vaillant, or Viessmann often cost more but offer longer warranties.
- Home Size – Larger homes need higher output boilers.
- Installation Difficulty – Older or complex systems may need extra work.
- Energy Efficiency – A-rated models are more efficient but pricier upfront.
Boiler Grants and Schemes in 2025
You may be eligible for government funding to help reduce the cost of a new boiler.
Boiler Upgrade Scheme (BUS)
- Offers up to £7,500 off the cost of installing a heat pump.
ECO4 Scheme
- Designed for low-income households to replace inefficient gas boilers.
Local Council Support
- Some councils provide grants or low-interest loans for energy improvements.
Always check your eligibility before purchasing to see if you can reduce your costs.
How to Save Money on Your New Boiler
Get multiple quotes – Compare at least three Gas Safe engineers.
Choose the right size – Don’t overpay for a boiler that’s too powerful.
Install during summer – Prices are lower and installers have better availability.
Look for long warranties – Choose models with at least 5–10 years of cover.
Add smart controls – Boost efficiency and cut down on monthly bills.
When to Replace Your Boiler
You should consider replacing your boiler if:
- It’s over 10–15 years old
- It needs frequent repairs or leaks often
- You notice inconsistent heating or unusual noises
- Your energy bills have increased noticeably
A modern A-rated boiler can improve your home’s energy efficiency by up to 30%, saving you hundreds of pounds every year.
Final Thoughts
So, how much does a new boiler cost in the UK?
For most homes, the total cost ranges between £2,500 and £4,500, including installation.
The right boiler depends on your home size, water usage, and budget. Always get advice from a Gas Safe registered engineer to ensure you choose the correct model and installation method.
A well-chosen boiler isn’t just about comfort — it’s an investment that can lower your energy bills, reduce carbon emissions, and give you peace of mind for years to come.