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Combi boiler prices and installation in 24 hrs

Combi boilers are undoubtedly more efficient and reliable than standard boilers of the past. Having a new model fitted can seem a large task; choosing the brand, working out the costs and finding a gas safe engineer to have it fitted. 

  • Combi Boiler installed from £1,549
  • Installed in 24 hours*
  • Free Gas Safe Registered Installation
  • No deposit and 0% interest available
  • Up to 10 years warranty
Get an instant online quote
New combi boiler

What is a combi boiler? 

A combi boiler (short for combination boiler) is a combination (the clue is in the name!) of a water heater and central heating boiler together in one compact unit.

They are now the most popular type of boiler fitted in homes across the UK. This is not only because of their compact design, but for being a lot more energy-efficient, eco-friendly and can keep your house warmer for longer!

Get a new combi boiler

Average combi boiler prices

With absolutely no hidden extras and your warranty comes as standard.

From only



NO deposit from


Per month 6.9% APR Representative*

Get a fixed price quote

Your new boiler package includes

  • Up to 10 year warranty
  • Flue kit worth up to £100 RRP
  • Magnetic filter worth up to £100 RRP
  • Web-enabled wireless thermostat
  • A chemical system flush 
  • Expert installation by a gas safe registered engineer
  • All fixtures, fittings and safety checks
*Representative Example  
Item value (Cash price) £1,549
Deposit £0
Total amount of credit £1,549
Agreement duration 120 months
Annual rate of interest 6.9% P.A
Representative APR 6.9% APR
120 monthly payments £17.74
Total amount payable £2,128.73


Who can apply for finance

  • Applicant must be 18 years or older on application date
  • In permanent UK residence for a minimum of 3 years

Fulfil one of the following employment criteria:

  • In regular, permanent employment (for a minimum of 16 hours a week)
  • Retired from regular employment
    Not working through disability
  • Self employed

The approval of your application depends on your financial circumstances and borrowing history.

How it works

No obligations quick online quote

Online quote

Choose your new boiler, payment method & installation date.

Gas safe registered engineer video and home survey


Our experts will check your chosen system is a perfect fit for your home.

Gas safe registered engineer boiler installation


Our engineers will come to install your new system at a time & date that suits you.

Customer service happy healthy boiler


We make sure you're happy with and give you the full VIP treatment.

How much does a new combi boiler cost?

When looking for a boiler replacement, one of the first things you will consider is exactly how much will it cost? Whether you’re looking for the cheapest boiler replacement available or to invest in a high-quality brand that will give you peace of mind and longevity; we have broken down the costs for you. 

New boilers can indeed be expensive but should be seen as an investment in making your home a more comfortable and indeed safer space to live in. 

The cost of a new boiler can also be made less overwhelming with our payment plans, which offer customers flexible ways to pay for top-rated boiler brands. From interest free to Buy Now Pay Later - allowing you to spread the cost over a more manageable period. 

Why choose a combi boiler?

There are many reasons why combi boilers are the most popular choice nowadays.

The benefits of opting for a combi include:

  • They heat water instantly, which reduces water wastage making them more cost-effective.
  • They are faster: Combi’s heat water directly from the mains on demand.
  • Powering your shower with a combi boiler means you no longer require a separate shower pump. This saves a lot of money and is also more reliable than a general shower pump.
  • There are lots of size options for a combi; meaning smaller homes can choose a more compact design,
  • There is less pipework which makes installation costs less expensive.
  • Cold water from combi boilers (your cold tap water) is guaranteed safe to drink.
  • As water comes straight from the mains, they are less likely to develop pressure problems. Sludge is also not as much of a concern for this reason.
Worcester Greenstar 4000 brand high quality combi

Worcester Bosch combi boiler

We offer a vast range of award-winning Worcester Bosch combi boilers. With a newly acquired stock of the Greenstar 4000 (updated 30i model) and the Greenstar 8000 life classic (LPG) combi models.

Every Worcerster Bosch Combi Boiler comes with a 10-year warranty and will be perfect for larger homes with energy-conscious customers.

Potterton Assure 36 kW affordable combi boiler

Baxi combi boiler

Baxi combi boilers are an efficient and durable choice, they use the right amount of fuel to meet the set central heating and water temperatures - saving you money on your fuel bills.

Get your Baxi installed by Boiler Plan with a free 5-year manufacturer-backed warranty on all parts, labour and call-outs.

Ideal Logic C30 affordable combi boiler

Ideal combi boiler

Representing the next generation in heating design, the Ideal combi boilers offer the very latest in heating technology together in a practical, compact unit that fits easily into any standard kitchen cupboard

This highly efficient system comes with a 2-year manufacturer-backed warranty that can be upgraded to 5 or 10 years.

Vaillant Ecotec Pro 30 affordable combi boiler

Vaillant combi boiler

Our range of Vaillant combi boilers combine the built-in quality, reliability and performance you’d expect from a which? best buy award-winning boiler.

With their simple design and approach, their highly efficient combi boilers have been awarded the Quiet Mark Accreditation and with us, you'll get a free 10-year warranty on all parts, labour and call-outs.

Can you switch to a combi boiler?

As the most common type of boiler in the UK, you can absolutely switch your central heating to a combi boiler. If you have a hot water heater in the airing cupboard and/or cold water storage in the loft a combi boiler will save you space, time and energy due to their process of heating water directly from your mains, providing instant hot water from the tap.

Combi conversions are available for all households, but they're incredibly efficient for 1-3 bedroom homes, anything after that will need a very powerful combi boiler of over 36kW.

What size of combi do you need?

Choosing the right combi boiler has a lot to do with how much demand is placed on your central heating based on the size of your property and how many bathrooms you have.

Here we look at how powerful your combi boiler has to be to work efficiently for the size of your home:

Number of bedrooms Number of bathrooms Combi Boiler Power (kW)
1 bed Flat 1 bathroom 24-28kW
2 bedroom flat/house 1 bathroom 25-30kW
3 bedroom house 2 bathrooms 30-35kW
4 bedroom house 2-3 bathrooms 35-40kW
5 bedroom house 3+ bathrooms 40kW+

*Next-day installation available if your boiler installation has been booked before 3 pm - we'll always aim to have your new boiler installed the next day, but this will be subject to engineer availability at the point of purchase confirmation. We'll always prioritise any installs for those who don't have any heating or hot water.

ˆOnline purchase discount - Applies to direct new customers only available on installations booked from 1/07/21. The £100 purchase discount will be added at the point of online purchase. The promotion is non-transferable and cannot be used in conjunction with any other offer.