How Much Does a New Boiler Cost in 2026? Fitted Prices

A fair fitted price for a new boiler in 2026 sits between roughly £1,900 and £4,500, and where you land in that range has far more to do with your house than with the boiler itself. If you have been searching how much does a new boiler cost and getting answers that range from suspiciously cheap to alarming, this article explains what the honest numbers look like, and exactly which parts of the job move the price up or down.

Everything below refers to fitted prices: the boiler, the labour, the flue, a system clean, a filter and the paperwork. A bare boiler price on a merchant website tells you almost nothing about what you will actually pay.

The short answer: 2026 fitted price ranges

For a typical three or four bedroom home around Bristol, these are the brackets most jobs fall into:

Like-for-like combi swap, same position: £1,900 to £2,800
Combi swap with the boiler moved to a new location: £2,400 to £3,500
System or conventional boiler replaced like for like: £2,200 to £3,200
Conversion from a system or conventional boiler to a combi: £2,800 to £4,500

Within each bracket, the biggest variables are the brand and output of the boiler, the length of the guarantee, and how much of the surrounding pipework needs attention. A premium boiler with a ten or twelve year guarantee will cost more up front than a budget model with five years of cover, and for most households it is worth the difference.

Rule of thumb: the cheapest quote and the most expensive quote for the same job usually differ because of what is left out, not because one firm is greedy. Compare what is included before you compare the number.

How much does a new boiler cost for a straight swap?

A straight swap is the simplest job in heating: the old boiler comes off the wall, the new one goes on in the same spot, and the existing pipework and flue position are reused where they are sound. One engineer can usually complete it in a day.

This is why a like-for-like combi swap sits at the bottom of the price range. You are paying for the boiler, a day of skilled labour, a new flue, a magnetic filter, a chemical flush of the system and the commissioning paperwork. If a quote for a straight swap comes in well under £1,900, ask what has been left out. Common omissions are the system clean, the filter, or registration of the guarantee, and each of those will cost you later.

Moving the boiler: why relocation adds hundreds, not tens

Moving a boiler from, say, an airing cupboard to the kitchen, or from the kitchen to the loft, sounds like a small change. In practice it means extending gas, water and heating pipework to the new position, running a new condensate drain, cutting a new flue route through the wall or roof, and making good afterwards.

Each of those tasks adds time, and some add materials: copper, fittings, flue extensions, possibly a plume kit if the flue would otherwise discharge near a window or a neighbour's boundary. A relocation typically adds £300 to £800 to a swap, more if the new position is a long way from the old one or the flue run is awkward.

Sometimes relocation is worth every penny. Freeing up a kitchen cupboard, or getting a noisy boiler out of a bedroom wall, is a genuine improvement to the house. Just go into it knowing it is a bigger job than a swap, and expect the quote to reflect that.

System-to-combi conversion: the biggest job on the list

If your home currently has a hot water cylinder, and often a cold water tank in the loft as well, switching to a combi is a conversion rather than a replacement. The combi heats water on demand, so the cylinder and tanks come out, the pipework that fed them is altered or capped, and the heating system is repiped to suit the new boiler.

That is why conversions sit at £2,800 to £4,500 and usually take two days rather than one. In return you get back the airing cupboard and loft space, you stop heating a tank of water you may not use, and you remove several older components that would each have failed eventually.

A conversion is not right for every home, though, and a good engineer will tell you when it is not. Larger households with two or more bathrooms in use at the same time often do better keeping a cylinder, because a combi can only serve one strong hot outlet at once. Mains water pressure matters too: a combi is only as good as the flow rate feeding it, which is one of the things a proper survey should measure before anyone quotes.

The right boiler for your house is decided by your hot water habits and your water main, not by what is on offer that month.

Gas pipework upgrades: the cost nobody mentions on the phone

Modern boilers demand more gas flow than the boilers they replace. Many older homes have a 15mm gas supply running to the boiler, which was fine for the appliance fitted twenty years ago but starves a new one. Regulations require the engineer to confirm the supply can deliver the correct pressure at full output, so if the pipe is undersized it must be upgraded, usually to 22mm, from the meter to the boiler.

Depending on the route the pipe has to take, this adds £150 to £500. It is a legitimate and necessary cost, but it is also the item most often missing from a quote given over the phone without a visit. If one firm surveys your house and includes a gas run upgrade, and another quotes cheaper without looking, the second quote is not really cheaper. It is incomplete.

What a proper fitted quote should include

Before you compare numbers, check each quote covers all of the following:

The boiler make, model and output, with the guarantee length in writing
Flue, plume kit if needed, and condensate drain
A chemical or power flush of the system, and inhibitor
A magnetic system filter, which many manufacturers require to honour the guarantee
Any gas pipework upgrade identified at the survey
Removal and disposal of the old boiler, cylinder and tanks where relevant
Building Regulations notification and registration of the guarantee with the manufacturer

Key takeaway: a quote produced without anyone visiting your home is a guess. Water pressure, gas pipe size, flue position and system condition can each move the price by hundreds of pounds, and none can be checked over the phone.

How to get an accurate price for your home

The reliable route is a short survey visit. A competent engineer will look at the existing boiler and flue, measure the gas run, test the mains flow and pressure, ask about your hot water use, and then put a fixed price in writing. Fixed means fixed: if the job takes longer than expected, that is the installer's problem, not yours.

We have been fitting and replacing boilers across Bristol and the surrounding villages since 2004, and every job we quote is priced this way, after a visit, with everything on the list above included. If your boiler is on its way out, or you simply want a firm number to plan around, call us or use the callback form and one of our Gas Safe registered engineers will come and give you a fixed fitted price with no obligation attached.