Buying Guides
New Boiler Cost in London: What to Expect
Reviewed by our Gas Safe registered engineers · Last updated 22 July 2026
A new boiler is a big spend, and online ‘average’ figures rarely match a real London quote. Here’s a realistic breakdown by boiler type and the factors that move the price, so you know what a fair quote looks like.
Quick answer: In London, a new boiler supplied and fitted typically runs £1,900–£3,500 for a straightforward like-for-like swap, more for a conversion or a complex install. A combi swap is usually the cheapest; a system boiler with a cylinder costs more; converting between types costs the most because of the pipework changes. The biggest price factors are the boiler type and model, whether you’re changing system type, and how much pipework and flue work the job needs.
By Type
Typical London prices by job
Guide prices for North London — your exact figure depends on the model, scope and access. Always insist on a fixed, itemised quote.
| The job | Typical London cost |
|---|---|
| Combi swap, like-for-like | £1,900–£3,000 |
| System boiler swap, like-for-like | £2,200–£3,500 |
| Regular (heat-only) swap | £1,900–£3,200 |
| Convert regular or system to combi | £2,800–£4,000 |
| Convert combi to system + cylinder | £3,000–£4,500 |
| Premium boiler upgrade | Add £400–£800 |
The Price
What’s included and what moves it
What a quote includes
The boiler and standard fittings, labour, a system flush or filter where needed, safe removal of the old unit, commissioning, and warranty registration. A good quote is a fixed price with these itemised — no vague ‘from’ figures.
What moves the price
Boiler type and model, whether you’re changing system type, the amount of pipework and flue work, moving the boiler’s location, and extras like a magnetic filter or smart thermostat. Access and the age of the existing system matter too.
Engineer Insight
The conversion premium
The number that catches people out is the conversion premium. Swapping like-for-like is the cheap route; changing from one system type to another means new pipework, sometimes removing tanks or adding a cylinder, and a longer job — so it costs noticeably more. Before you compare quotes, make sure they’re for the same scope. We give a fixed price with everything itemised, so you’re not comparing our full quote against someone else’s ‘from’ headline.
Add-ons
Common extras and their cost
Typical North London guide prices — you’ll always get an upfront quote before any work starts.
FAQs
New boiler cost — your questions answered
How much does a new boiler cost in London?
Typically £1,900–£3,500 supplied and fitted for a like-for-like swap, depending on the boiler type and model. Conversions between system types cost more because of the extra pipework and components.
Why is a combi cheaper to fit than a system boiler?
A combi needs no cylinder or tanks, so there’s less to install. A system boiler adds a cylinder and associated pipework, and converting between types adds even more work — which is reflected in the price.
What’s included in a new boiler installation?
The boiler and standard fittings, labour, safe removal of the old unit, a system flush or filter where needed, commissioning, and warranty registration. Ask for a fixed price with these itemised.
Why do boiler quotes vary so much?
Because scope varies — a like-for-like swap and a full system conversion are very different jobs. Some quotes are ‘from’ headlines that exclude extras. Compare like-for-like, fully-itemised fixed prices.
Is it worth paying more for a premium boiler?
Sometimes — premium models often come with longer warranties and quieter operation. But a well-installed mid-range boiler is reliable too. Weigh the warranty and running costs, not just the badge.
Related
Related guides
Repair or replace — which makes sense.
Read guideBuying GuidesCombi Boiler GuideThe cheapest type to fit.
Read guideBuying GuidesSystem Boiler GuideFor bigger homes with a cylinder.
Read guideBuying GuidesBest Boiler BrandsWhere your money actually goes.
Read guideEnergy SavingBoiler Efficiency GuideLower running costs after fitting.
Read guideMaintenanceSigns Your Boiler Needs ServicingWhen a repair points to replacement.
Read guideBrowse all Buying Guides, or head back to the Help & Advice Centre.
Want a real quote, not a ‘from’ figure?
Book a Gas Safe engineer for a fixed-price, itemised quote on the right boiler for your home, or call. North London, upfront pricing, no upsell.
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