Combi Boiler Prices & Installation Costs

Thinking about the cost of a new boiler? If you’re also thinking about what a new combi boiler might cost you, well you’ve come to the right place.

Combi boilers are excellent choices for homes with smaller heating needs and they can either be gas-powered or electric.

This article will break down everything you need to know, including boiler prices from the best brands on the market, average installation costs, running costs, and what you might expect to spend on maintenance.

We’ve also included insights on how to choose the right combi boiler based on the size of your home, your energy needs, and budget (with bonus tips on warranties and any financing options too!).

PS We fit new boilers with gas safe installation nationwide. Simply answer these questions, get your fixed price and you could get it installed as quick as tomorrow.

Key Points

• Most combi boilers cost between £730 and £2,500 for the unit alone.

• It costs between £500 and £1,500 to install a combi boiler (labour).

• A new combi boiler can save you up to 30% on your energy bills.

• You can get a new combi boiler on finance if you can’t afford the upfront cost.

• Government grants to have a boiler fitted are now rare.

What is a combi boiler?

Before we get carried away with costs, let’s quickly explain what a combi boiler is. Combi boilers have the power to heat water on demand, so the moment you turn on your shower, your combi boiler will kick in to provide warm water almost instantaneously.

This means you don’t need a bulky storage tank, so a combi boiler takes up much less space. The downside to a combi boiler is that unless it’s an especially powerful model, it might struggle to provide hot water for more than one bathroom at a time.

If your home has substantial heating needs, you might want to consider a system boiler.

Is a combi boiler good for the planet?

A combi boiler’s eco-friendly status hinges on it being electric or gas-powered, as gas is a fossil fuel after all, and those won’t last forever. Plus, gas releases carbon emissions when it’s burned.

However, modern combi boilers nowadays are super efficient, especially when compared to their older ancestors! And, almost all combi boilers use condensing technology, which means boilers capture and reuse heat that would normally go to waste.

Also, combi boilers that use liquefied petroleum gas (LPG), are even better for the environment, because LPG is a cleaner fuel than natural gas.

PS Check out or review of the best combi boilers availble in the UK in the video below:

How much does a combi boiler cost in the UK?

The cost of a combi boiler will depend on several factors, including brand, model, power output, and how efficient it is.

For cheaper combi boilers, you’ve got something like a Baxi 200 Combi with a 24 kilowatt (kW) output, which’ll cost roughly £730 for the unit alone. Then you can go all the way up to a premium boiler such as the Worcester Bosch Greenstar 8000 with a 45 kW output, which can cost around £2,500 (depending on the model).

Sometimes you don’t need to spend more to get the right boiler for your home, as buying the expensive Greenstar 8000 wouldn’t actually be worth it if your home has less than 15 radiators. If your heating needs are small, a Baxi 200 Combi would be more than enough!

Back to costs, you’ll need to consider what you’ll spend on installation, which can add between £1,000 to £2,000.

So roughly speaking, a new combi boiler might cost anywhere from £1,500 to £4,500.

You’ll also pay more or less depending on whether your combi boiler is powered by gas, LPG, oil, or electricity.

Combi boiler costs by brand

We’ve covered the combi boiler costs of some of the most popular brands in the UK, including Worcester Bosch, Viessmann, and Ideal. Each of the sections below has a table showing an example of a low and high cost combi boiler from the brand.

Also, all costs listed are for the boiler alone — installation costs and any other additional things you need aren’t included.

Baxi combi boiler prices

British manufacturer Baxi has been operating since 1866, so you know you’re getting a brand that’s stood the test of time.

Its boilers are top notch too, and generally speaking, Baxi boilers cost less than premium brands such as Viessmann or Worcester Bosch (without a sacrifice in build quality).

Looking at the standalone cost of Baxi combi boilers, they are typically priced between £730 to £1,350.

Ideal combi boiler prices

Ideal is a boiler brand that has been around for decades, with hundreds of thousands of UK homes using its reliable boilers.

Generally, though, its warranty periods leave a lot to be desired and most standard warranties are just two years.

The average price range for Ideal boilers is between £780 and £1,500.

Vaillant combi boiler prices

Vaillant is the first genuinely premium boiler brand in this list, and it’s a tag the German company has most definitely earnt.

It’s won multiple awards and in our opinion, Vaillant produces some of the best boilers on the market. These boilers are incredibly simple to repair too, which is fantastic news for our engineers, but better news for you as you’ll pay less per hour for the inevitably shorter time to repair!

For a new Vaillant combi boiler, you’ll pay between £700 to £2,000.

Viessmann combi boiler prices

Viessmann is one of our favourite boiler brands, and it’s another manufacturer showing how hard German engineering is to beat!

Just look at the upper levels of some of its most efficient boilers — 98% no less. You can see what we think of Viessmann in our reviews on Viessmann boilers.

Viessman combi boiler costs start from around £900, going up to £2,000 or so.

Worcester Bosch combi boiler prices

Worcester Bosch started just as Worcester part all the way back in 1962, spending decades building a reputation as one of the UK’s best boiler manufacturers. It went from one of the best to probably the best when it joined with German engineering giant Bosch in 1992.

Since then, the company has worked hard to continuously innovate its boiler range, culminating in certified classics such as the Greenstar 4000 (our best overall combi boiler).

How much does it cost to install a combi boiler?

When considering buying a new combi boiler, don’t forget to factor in installation costs! You won’t be able to avoid this, unfortunately.

And as much as you might want to DIY the whole thing, trust us when we say it’s not worth it. Boilers funnel highly explosive gas through their systems to keep your home warm. You don’t want a dodgy installation leaking said gas into your home.

You should use an accredited installer instead (hello, that’s us!) to avoid a worst-case scenario. It takes a lot of work and effort to become accredited, because there’s a lot of safety to consider when installing a boiler.

Installing a new combi boiler adds between £500 and £1,500 to the total cost.

It’ll cost less if you’re simply swapping an old combi boiler for a new one, and more if you’re replacing either a system or conventional boiler with a combi model.

How much does it cost to run a combi boiler?

The cost of running a combi boiler depends on how it's powered. Just to keep this a bit simpler, we’ll compare a typical gas combi boiler with an electric combi boiler — the two most common types of combi boilers in the UK.

Running a gas-powered combi boiler on current fuel prices (correct as of October 2024) will cost the average three-bedroom household in the UK £120 per month.

An electric boiler on the other hand, will cost the same household about £206 per month (based on the current average electricity cost of 24.50p per kWh). Electricity is often more expensive than gas per kWh and heating a home with electricity requires a lot of energy.

Does a new combi boiler save you money?

Almost certainly, the average UK home could save as much as £355 per year (or roughly 30% on your energy bill) by buying a new boiler, according to the Energy Saving Trust.

Saving money is all but guaranteed if your boiler is particularly old, as older models are very inefficient compared to modern boilers.

Some older boilers have efficiency ratings as low as 60%, compared to the typical 92% of modern condensing boilers. In other words, for every £1 you spend on heating, an older boiler is effectively chucking 40p out the window.

Over time, this wasted money really adds up and you’ll be potentially wasting hundreds of pounds a year.

Combi boiler maintenance costs

It might seem like a pain, but you should definitely pay to get your boiler serviced on the regular. Doing so is essential to avoiding costly repairs or even having to get a new boiler sooner than you normally would need to.

Boiler service costs vary depending on the boiler type, what sort of maintenance you require, and whether you need replacement parts, but on average you’ll pay between £100 and £500 for most repairs.

Keep it in mind that the latter £500 figure is if you need emergency repairs. Most combi boiler service costs won’t go over £150 (including labour and material costs).

You could consider getting boiler cover too. How much this costs depends on the level of cover you’re after — it costs more per part of the boiler you cover, for example.

We’ve written a guide on whether boiler cover is worth it — give it a read!

Can You Buy a Combi Boiler On Finance?

Yes, combi boilers are available on finance and it can be a great option if you need a new boiler but can’t afford to buy one outright. Boiler finance allows you to spread the cost of a new boiler into monthly payments.

You don’t normally need to pay a deposit, but doing so will reduce the overall amount you pay during a finance term.

We offer combi boilers on finance here at Heatable. You can read all about boiler finance in our helpful guide (plus you’ll get an idea for what sort of finance plans are available for different boiler brands).

Are There Any Government Grants for Combi Boilers?

If you don’t want to pay the full price of a new boiler, and you don’t want to get a boiler on finance, you could always try qualifying for a government boiler grant.

The main one is ECO4, which is the fourth and final stage of the UK government’s Energy Company Obligation scheme. ECO4 is designed to help lower-income households (or tenants on a low income) make their home more energy efficient.

It runs from April 2022 until April 2026, and if you’re eligible ECO4 is well worth considering!

Be aware though that the primary aim of ECO4 is to improve energy efficiency, and that means leading with a fabric-first approach — basically, insulation is the priority here. ECO4 only obligates large energy suppliers (those with 150,000 or more customers) to carry out 5,000 boiler replacements a year.

Get a Quote For A Combi Boiler Today 

If you’re aiming to get the best deal on a new boiler, consider getting a quote from us, here’s why:

• Gas Safe installation within 24 hours.

• Thousands of satisfied customers with an average score of 4.9 on Trustpilot, surpassing the market leader.

• Which? Trusted Trader: Heatable is proudly recognised as a Which? Trusted Trader.

• Price match guarantee: We will match any like-for-like cheaper quote.

• Flexible payment options, including interest-free finance.

• Up to 12-year guarantee on selected boilers.

• Fixed price guarantee: No hidden costs.

• Save your quote and decide later.

• Get an instant fixed price on a new boiler, here.

To learn more about boilers, visit our advice section, check out our YouTube channel, or read customer testimonials here.