Boiler replacement cost UK 2026

A like-for-like combi boiler swap in 2026 costs £2,100–£3,200 fitted. Switching boiler types or relocating the boiler adds £800–£2,000. Worcester Bosch and Vaillant lead the market on warranty and resale.

How much does this cost in the UK in 2026?

The typical UK price range is £2,100–£5,000, with the average household paying around £3,000. Use the free calculator below to get a personalised estimate.

Free boiler replacement cost uk 2026 calculator

What affects the cost?

• Boiler type — combi, system, or heat-only
• Boiler brand and warranty length (10-year vs 5-year)
• kW output — sized to your home (24 kW typical for a 3-bed semi)
• Whether the boiler is moving location
• Power flush of the existing system (£350–£700)
• New flue, magnetic filter, and thermostat
• Gas Safe engineer's callout rates (£300–£550/day labour)

Cost breakdown

Cost by UK region

Regional pricing varies by up to 50 %, mostly driven by labour rates. These multipliers apply to the base UK cost:

Planning permission?

Not required; Gas Safe registered engineer required by law

How long does it take?

1–3 days typical, plus design and approvals time beforehand.

DIY vs Professional

Difficulty: Pro required. UK building regulations and Part P/Gas Safe rules mean most of this work must be done by registered professionals. Even where DIY is permitted, paying a pro is usually faster and more reliable.

How to save money

• Always insist on a power flush and magnetic filter when replacing — the boiler's warranty often depends on it
• Get three Gas Safe quotes via Checkatrade or the Gas Safe Register
• A higher-warranty boiler (10-year Worcester or Vaillant) often costs less over the life than a budget brand
• Replace TRVs at the same time — only £15 each but you have to drain down anyway
• Consider a heat pump if you're due for a full system replace and have outdoor space

How to find a trusted tradesperson

Always get at least three written quotes. Use a vetted UK trade network for peace of mind:

• Checkatrade — vetted local trades with reviews
• MyBuilder — reviewed builders by job type
• Bark — get quotes from local pros

Or use the calculator above to get 3 free quotes direct to your inbox.

Frequently asked questions

How long does a boiler last?

A well-serviced modern combi lasts 12–15 years. System and heat-only boilers can last 15–20 years. Annual service is essential for warranty.

Which is the best boiler brand in 2026?

Which? consistently rates Worcester Bosch, Viessmann and Vaillant in the top three for reliability. Worcester has the strongest UK service network; Vaillant the longest warranties.

Can I get a grant for a new boiler?

There is no general boiler grant in 2026, but ECO4 and the Boiler Upgrade Scheme can support heat pump installs (up to £7,500) for eligible homes. Always check eligibility via Simple Energy Advice or your supplier.

Get 3 free quotes

Use the calculator above to get an estimate, then submit your details to receive 3 free quotes from vetted local tradespeople. No signup, no spam.

Disclaimer: Prices are guide ranges based on 2026 UK market data. Get quotes from local tradespeople for accurate pricing.