Boiler Installation London — From £1,399

Boiler installation in London — everything you need to know

A new boiler installation in London is one of the most significant home improvements a London property owner can make. A new A-rated combi boiler replaces an old, inefficient heating system and can reduce gas bills by up to 30% annually — saving an estimated £200 to £400 per year compared to a boiler more than 10 years old. Our Gas Safe registered engineers install new combi boilers across every London borough, with fixed prices starting from £1,399 fully installed.

What is a combi boiler and why do most London homes need one?

A combi boiler (combination boiler) is the most popular type of boiler in the UK and is ideal for the majority of London properties. A combi boiler provides both central heating and instant hot water from a single compact unit, without the need for a separate hot water cylinder or cold water tank in the loft. This makes it particularly well-suited to London's flats, terraced houses and smaller properties where space is at a premium.

Unlike conventional system boilers, a combi boiler heats water directly from the mains on demand — meaning you never run out of hot water and there is no energy wasted heating a tank. For properties with one bathroom and up to 3 bedrooms, a combi boiler is almost always the most efficient and cost-effective choice.

How much does boiler installation cost in London?

New combi boiler installation in London starts from £1,399 fully installed — including the new boiler, all parts, labour, Gas Safe certificate and 5-year warranty. London installations typically cost more than the national average due to higher labour costs and the complexity of accessing older London properties, but our fixed prices are guaranteed with no hidden charges added after the job is completed.

The final price depends on the boiler brand and model selected, the size (kW output) required for your property, and whether any additional work is needed — such as new pipework, magnetic filter fitting or system flushing. Our engineers assess your property and confirm the exact fixed price before any work begins.

Which boiler brands do our London engineers install?

Our Gas Safe engineers in London install all major boiler brands:

• Worcester Bosch — the UK's most trusted boiler brand. Worcester Bosch combi boilers are known for exceptional reliability and efficiency, and come with up to 10-year manufacturer warranty
• Vaillant — German engineering excellence. Vaillant ecoTEC combi boilers are extremely energy efficient and among the quietest available
• Ideal — reliable, affordable and widely serviced across London. Popular choice for London buy-to-let and HMO properties
• Baxi — compact dimensions make Baxi combi boilers ideal for London flats and properties with limited cupboard space
• Glow-worm, Alpha, Viessmann, Potterton — all other major brands also installed across London

How long does boiler installation take in London?

Most new combi boiler installations in London are completed in 4 to 6 hours — within a single day. A like-for-like replacement (same type of boiler, same location) takes 4 to 5 hours. A first-time installation or a conversion from a system boiler may take 6 to 8 hours and in some cases requires a second day. Our engineers confirm the expected duration when carrying out the initial assessment.

Is a Gas Safe engineer required for boiler installation in London?

Yes. Under the Gas Safety (Installation and Use) Regulations 1998, all boiler installations in London — and across the UK — must be carried out by a Gas Safe registered engineer. This is a legal requirement with no exceptions. A boiler installed by an unregistered person is illegal, can cause gas leaks, fires and carbon monoxide poisoning, and will invalidate your home insurance and void the boiler warranty. All our London boiler engineers are fully Gas Safe registered and carry valid ID cards verifiable at gassaferegister.co.uk.

Boiler installation for London landlords — what you need to know

London landlords have specific legal obligations around boiler installation and gas safety. Under the Gas Safety (Installation and Use) Regulations 1998:

• All gas appliances including boilers must be installed by a Gas Safe registered engineer
• A Gas Safe installation certificate must be obtained and retained after every installation
• An annual gas safety check (CP12 certificate) must be carried out on all gas appliances in rental properties
• Tenants must receive a copy of the CP12 certificate within 28 days of completion

Our landlord boiler service at boilerinstallerlondon.uk/landlord-boiler-services-london/ covers all of these requirements with fixed pricing and fast turnaround across all London boroughs.