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How Much Does It Cost to Replace a Boiler in London in 2026?

A straightforward like-for-like combi boiler replacement in London typically costs £1,800–£2,500 (mid-range models up to about £2,900; premium models £2,500–£3,500) — and you can compare free quotes from verified London heating engineers on Energy North with no fees and no obligation.

If your boiler is over 10–12 years old, losing pressure, or leaking, replacement is usually more cost-effective than repeated repairs. Below is a clear 2026 breakdown of what a new boiler actually costs in London, what drives the price, and how the government's £7,500 heat pump grant fits in if you're considering going low-carbon.

What a new boiler costs in London (2026)

Across the UK, the average cost of a new boiler plus installation in 2026 is around £2,400 for a mid-range unit and a day's labour from a Gas Safe registered engineer on a standard like-for-like combi swap.

London runs higher. Labour rates in the capital are typically 20–30% above the national average, adding roughly £200–£500 to an equivalent job elsewhere. In practice:

The boiler unit itself ranges from roughly £1,050–£2,250 for a small 24–27kW combi, up to £1,400–£3,700 for a larger 35–42kW unit. Labour on a straightforward like-for-like combi replacement is around £550–£800, though complex jobs can push labour toward £1,000+.

What pushes the price up

The single biggest variable is whether it's a simple swap or a system change. Moving from a system or conventional boiler to a combi — relocating the unit, upgrading pipework, adding a magnetic filter, or fitting a new flue — all add cost. Older London properties with awkward access, non-standard pipework, or the need for a chemical power flush also sit at the higher end. Always get the boiler size (kW output) matched to your home rather than simply replacing like-for-like on assumption.

Should you consider a heat pump instead?

If you're replacing an ageing fossil-fuel boiler, it's worth knowing about the Boiler Upgrade Scheme (BUS) in England and Wales. In 2026 it pays a £7,500 grant toward an air-source or ground-source heat pump, with no income test. The EPC insulation "block" was removed in 2026, so outstanding loft or cavity-wall recommendations no longer stop you qualifying. Your installer must be MCS certified and a member of an approved consumer code (such as RECC or HIES).

From 21 July 2026 to 31 March 2027, eligible off-gas-grid properties replacing oil or LPG heating can receive an enhanced £9,000 grant. A heat pump costs more upfront than a combi, but the grant closes much of the gap — worth pricing both when you replace.

Whichever route you choose, the smart move is to compare several verified local quotes rather than accepting the first number. On Energy North, homeowners post a boiler job for free and verified London tradespeople reply directly — no subscriptions, no commission, and your details are never resold to five rival firms.

Frequently asked questions

How much is a new combi boiler fitted in London in 2026? Expect roughly £1,800–£2,500 for a like-for-like combi swap, rising to about £2,900 for a mid-range unit and £2,500–£3,500 for premium models, reflecting London's higher labour rates.

Is it cheaper to repair or replace an old boiler? If your boiler is over 10–12 years old and needs frequent repairs, replacement usually works out cheaper over time thanks to better efficiency and fewer breakdowns. A one-off minor repair on a newer boiler is generally worth doing.

Do I legally need a Gas Safe engineer to fit a boiler? Yes. Any gas boiler installation in the UK must be carried out by a Gas Safe registered engineer. Always check the engineer's Gas Safe ID before work begins.

What is the Boiler Upgrade Scheme worth in 2026? It pays £7,500 toward an air- or ground-source heat pump in England and Wales with no income test, or £9,000 for eligible off-gas-grid oil/LPG homes from 21 July 2026. Installers must be MCS certified.

How long does a boiler replacement take? A straightforward like-for-like combi swap is usually a one-day job. Converting from a system boiler to a combi, or relocating the unit, can take two to three days.

Get free quotes from verified London heating engineers

Energy North is a UK trades marketplace where homeowners post jobs for free and verified local tradespeople reply direct. No subscriptions, 0% commission, and free for tradespeople in 2026. Compare boiler installation quotes in London.

Related guides: Find a Gas Safe heating engineer in London · EICR electrical safety certificate cost in London · EV charger installation cost & grants

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