Boiler Installation UK · Gas Safe Registered Engineers
Replace or upgrade your boiler with a vetted, Gas Safe registered heating engineer. A like-for-like combi swap starts from £2,200 fitted, with Building Regulations notification, system flush and warranty all handled for you. Compare itemised quotes before you book.
Boiler Installation for Every Home
From a straight combi swap in a flat to a full system boiler with a new cylinder or a conversion — vetted, Gas Safe registered engineers for every job.
Swapping an old combi for a new one in the same spot. Usually a one-day job. The most common and affordable upgrade, with a new flue, filter and controls included.
Get quotes →A system or conventional (heat-only) boiler feeding a hot-water cylinder, suited to larger homes and multiple bathrooms. Allow one to two days plus a new or upgraded cylinder.
Get quotes →Converting between boiler types or moving the boiler to a new location. The most involved job, with extra pipework, condensate routing and making good. Allow two to three days.
Get quotes →Boiler Installation Cost Drivers
| Cost driver | Typical effect | When it applies |
|---|---|---|
| Boiler type | Main price factor | Combi, system or conventional — and whether you change type |
| Brand & warranty | +£200 – £900 | Premium brands and longer guarantees cost more upfront |
| Cylinder & pipework | +£400 – £1,500 | New cylinder, moved pipes or upsized gas supply |
| Powerflush / filter | +£300 – £700 | Recommended on older systems; a magnetic filter protects the new boiler |
| Relocation & flue | Varies | Moving the boiler or re-routing the flue adds labour and materials |
A like-for-like combi swap usually sits inside the £2,200–£3,500 range. London and the South East run higher than the national average. A full boiler cost breakdown is in our cost guide.
3 Steps to a Gas Safe Boiler Quote
Tell us about your boiler
60-second form. Your current boiler type, the number of bathrooms, where it lives and any faults. No phone, no jargon.
Get matched to engineers
Up to 3 vetted, Gas Safe registered heating engineers near you. We pre-screen on registration and reviews.
Compare & book
Itemised quotes within 24 hours. Compare the boiler brand, warranty length, filter and flush before you book.
Get Accurate Quotes From Boiler Installers
The price depends on the boiler type and brand, your cylinder, the pipework and whether the boiler is moving. The most accurate quotes come from a quick survey — get up to 3 vetted, Gas Safe registered engineers to assess and quote, completely free.
What a Boiler Installation Includes (2026)
A boiler installation is more than the appliance itself. Knowing what is included helps you compare quotes fairly.
🔥 The boiler & flue
The new combi, system or conventional boiler plus a new flue, fitted and commissioned to the manufacturer’s instructions so your warranty stays valid.
📜 Building Regs notification
Every gas boiler installation must be notified to Building Control. Your Gas Safe registered engineer self-certifies this and you receive a compliance certificate — keep it with your warranty.
🧲 Magnetic filter & powerflush
A system flush (or powerflush on older systems) clears sludge, and a magnetic filter is fitted to protect the new boiler. Many warranties require both.
🌡️ Controls & thermostat
A modern programmable or smart thermostat and TRVs help you control heating room by room and meet efficiency requirements.
💧 Cylinder (if needed)
System and conventional boilers feed a hot-water cylinder. A new or upsized cylinder may be fitted for larger homes or extra bathrooms.
🛡️ Warranty & registration
The engineer registers the boiler with the manufacturer so the guarantee (often 7–12 years on premium brands) is valid from day one.
Boiler Grants & the Warm Homes Scheme
Some households can get help towards a new heating system. Here is what is available in 2026 and how to check eligibility.
💷 Boiler Upgrade Scheme
The Boiler Upgrade Scheme (BUS) offers grants towards heat pumps rather than gas boilers. If you are open to a low-carbon system, your installer can explain whether it suits your home. See our step-by-step guide to claiming a Boiler Upgrade Scheme grant.
🏠 Warm Homes & ECO4
The Warm Homes scheme and ECO4 can help lower-income or off-gas households replace an inefficient boiler. Your installer can tell you whether your home and income qualify before you commit.
📊 Should you repair or replace?
If your boiler is over 10–12 years old, breaking down repeatedly or costly to run, replacement usually pays back through lower bills and a long warranty. A survey gives you a clear answer.
⚡ Combi vs system vs heat-only
The right boiler depends on your home size, water pressure and number of bathrooms. Our comparison of boiler types explains which suits you.
Boiler Installation FAQs
Boiler Installers by Town
Vetted, Gas Safe registered boiler installers across UK towns:
Boiler Installation Guides & Costs
Planning a new boiler? These guides explain costs, grants and how to choose the right boiler type.
Boiler Replacement Cost (2026)
A full breakdown of new boiler costs by type, brand and job complexity, with money-saving tips.
Read more →How Much Does a New Boiler Cost?
Real 2026 UK price ranges for combi, system and conventional boilers, plus what drives the final figure.
Read more →Combi vs System vs Heat-Only
Compare the three boiler types side by side to find the right one for your home and water use.
Read more →Claim a Boiler Upgrade Scheme Grant
A step-by-step guide to the Boiler Upgrade Scheme and other 2026 heating grants.
Read more →Looking for local quotes? Find vetted trades in your town →