Depending on how old and inefficient your existing boiler is, you could be wasting money every day that you use it. Modern boilers could save you a fortune over the long term.

Old boilers usually suffer from:

• noise on startup and when running
• slow warm-up times
• frequent breakdowns and higher repair bills

But how much does it cost to have a new boiler supplied and fitted?

And what about hidden or unexpected costs?

How Much Do YOU Think a New Boiler Will Be?

I know this sounds like an odd question.

After all, you came here looking for boiler prices, but we are conducting research into how much customers think a new combi boiler installation will cost.

The question below is entirely optional. You can skip it if you wish.

Explore Our Impartial New Boiler Cost Guide

Our price guide below is 100% impartial and is based on our many years of experience.

Here you’ll discover:

• exactly what work is involved with a boiler replacement
• how much a new condensing boiler costs
• a look at regular gas boilers
• compulsory extra costs you might be charged
• optional extras that we think you should budget for
• how long the work will take

What Work is Involved With a Boiler Installation and How Long Will it Take?

There are several options to choose from:

See which example meets your requirements:

1. replace a regular boiler like-for-like
2. replace a combi boiler like-for-like
3. replace a regular boiler with a combi boiler, leaving the hot water cylinder tank in place
4. replace a regular boiler with a combi boiler, removing the hot water cylinder tank

1 – Replacing a regular boiler in the same location on a like-for-like basis is the cheapest option and excluding extras and additional items, you’ll be looking at around £1800. The work will take between 5 and 8 hours.

2 – If you want a new combi boiler in the same location as an older combi, you’ll be looking at around £1900 excluding extras and the work is expected to take between 5 and 8 hours.

3 – One option for you to consider is replacing a regular boiler with a combi boiler, but leaving the hot water cylinder tank in place. This type of installation is often cheaper than removing the tank and pipework BUT your new system won’t be as efficient as it could be. Expect to pay around £2000 excluding extras and the work will take around a day,

4 – A popular option is to replace an old regular boiler with a combi boiler and remove the hot water cylinder tank so the entire house is running directly off the combi. This is the most efficient system but the installation costs are higher as the tank and pipework needs to be removed and new pipework put in its place. Expect this work to take around 2.5 days and cost around £2500 for a basic installation, excluding the extras specified below.

Extra Costs – Optional and Compulsory

The prices displayed above are for a basic installation and exclude the following optional, compulsory and potential extra costs:

Power flushing is the process of pumping water and chemicals through the pipes and radiators to flush out debris and rust that could be clogging the system making it inefficient. Installers usually recommend a power flush when a new boiler is installed. No boiler, regardless of its cost, will run efficiently if the system is clogged with particles and rust. The cost of a power flush varies but usually depends on the number of radiators in your house. This page contains a guide to power flushing costs.

Heating controls and thermostats are a personal choice. Wired analogue systems are cheap and cost from £35 for the materials. Wireless systems; those compatible with apps and mobile phones etc cost more. Good digital systems cost upwards of £100. Whether you want to keep your existing controls or upgrade them will depend on your preferences and the type of heating system you have chosen. Relocating a wired unit will cost more than keeping the new one in the same location.

The flue may need to be replaced. This depends on the type of boiler. The prices vary.

Combi boilers require a condensing pipe, this is usually inserted through the wall and into a drain. How much pipe is required and how far away the drain is will are factors that affect the price of this aspect of the installation. In most cases, this pipe is cheap to buy and install but in some corner cases, additional work could be required.

Relocating a Boiler

This is the most expensive type of installation and is usually carried out when a kitchen or other part of the house is being remodelled.

The work involves removing and relocating both water and gas pipes and also some finishing off work such as plastering and decorating.

Expect a typical combi boiler, in a new location, to cost you around £2500 this work will take between one and a half days and two and a half days to complete, depending on location.

About Our Prices

To keep things simple, all of our boiler prices on this page assume a mid-range product that is suitable for a three-bedroom house.

The cost of the materials for a smaller/larger house will vary but the installation fee is roughly the same.

We also assume that the work is done by a mid-sized company, not a large business such as British Gas who’ll charge more and not by a sole trader type business that’ll probably be cheaper.

We have many years’ experience in the home improvement sector but our work area has always been in the south and southeast of the United Kingdom. Others areas, particularly those in the north of the UK may be cheaper, especially if you avoid big companies like British Gas.

Why We Think a Combi Boiler is Best But Might Not be Right For You

For most households, we feel that a combi boiler is the best option.

Here’s why:

• you’ll get unlimited hot water whenever you want straight from the mains.
• they’re fast to install and often have fewer parts than a regular boiler.
• you don’t need a hot water tank, so no waiting for hot water and you can free up space.
• you can have the option of a hot water tank if you want one.

Combi boilers aren’t always the best option if:

• you have poor water pressure from the mains, you may experience pressure issues when you use more than one tap or shower at a time.
• it does take a good few seconds for the hot water to come through, especially to taps and showers that are located far from the boiler, ie upstairs.

Avoid The Cowboys But Still Get a Good Deal With Our 6 Killer Tips

The easy option is to choose a well-known company such as British Gas, they are usually very reliable, the workmanship, for the most part, is very good and they honour their warranties.

The caveat is the price – British Gas and other large companies have such huge overheads that they often charge considerably more than smaller firms and local sole trader installers.

Here are our tips for getting a great deal while avoiding the cowboys:

1. ask close friends and relatives for a recommendation. We feel that a recommendation from a close friend is worth a hundred anonymous reviews you can find online and we mean that literally.
2. if you use Facebook, go and ask your connections there if anyone knows of a good installer. Don’t forget to check for local Facebook groups which a great way to find local trustworthy tradespeople. Some smaller businesses such as sole traders don’t pay for any advertising at all, they rely entirely on reviews and recommendations on local groups and forums.
3. services like Checkatrade, MyHammer and Rated People are great places to read reviews but work best when the business has at least 50 reviews. Not every business with few reviews is a bad business but with so few reviews you shouldn’t rely entirely on them.
4. check the Gas Safe Register here (formally known as the Corgi Register).
5. ask your chosen firm for the name of the installer and check their name on the register. We suggest you do this because some firms are Gas Safe registered but they either sub-contract the work to others or the trainee is left to do most of the work.
6. ask for references and follow them up by phoning them and asking some questions. A genuine installer or company with a good track record will have plenty of previous customers that would be happy to act as a reference.

Get a Quote

If you would like to get a fixed quote, just hit the link below to see how our partner can help you:

This guide was written by Danny Woodley and was last updated in April 2022.

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Explore our full list of detailed price guides here.