Imagine a home where every room feels warm and cosy while your energy bills remain in check. The best gas boilers available in the UK can offer you exactly this.
Gas is the most popular fuel type in the UK, with around 85% of homes being powered by natural gas. This is largely due to gas being one of the more affordable fuel options and the majority of homes being connected to the gas grid.
In this article, we’ll delve deeper into the features, benefits, and costs of the UK’s best gas boilers. This way, you can easily compare the top models available, enabling you to make an informed decision that aligns with your home’s needs and budget.
As well as comparing the best gas boiler models, it’s also critical to compare installers. This is because different installers offer different rates, so by comparing multiple installers, you not only avoid being ripped off, but also ensure you’re getting the best deal.
However, finding a trustworthy and qualified heating engineer to install your new gas boiler can be tricky and take up hours of your time. Thankfully, Boiler Guide can help you.
By filling in our quick form, we can connect you with up to 3 vetted heating engineers from our network. Click the button below to get your free, non-binding quotes now and select the best deal.
To save you time and reduce the stress of finding the best gas boiler, we've done the leg work for you. By researching the biggest brands, taking an indepth look at their latest and greatest boilers, we've compared customer reviews, industry awards and stand-out technology to find the best 5 gas boilers on the market today.
For each boiler, we've also asked the important questions:
How energy efficient is it? (Can it save you money on bills?)
Is it suitable for homes of different sizes?
Is it future proof? (Will it last the test of time and is there a long warranty to cover it?)
What's the environmental impact? And is this model ready
for future changes?
Each boiler in our list is available in different types and sizes to suit all homes, but if you would like more tips on buying a new gas boiler, check out our complete guide to finding the best boiler deal.
A recent Boiler Guide survey uncovered the top 5 brands most commonly installed (and most-loved) by homeowners. We've used the results, in the graph shown below, to form our best gas boilers list, by researching the very best boilers these popular brands have to offer.
1. Worcester Bosch Greenstar 4000
Price Range: £990 – £1,200 (excl. installation)
Types Available: Combi, System
Home Sizes: Small – Large
Ranked as the number 1 choice of boiler brand in the recent Boiler Guide survey, Worcester Bosch has proven to be a popular, trusted manufacturer amongst home owners.
The Greenstar range is consistently rated highly for reliability and quality and the new 4000 model, released in 2021, was quickly awarded as a 'Which? Best Buy' – so you can see why it's earned a spot in our top 5.
Worcester Bosch have stated the Greenstar 4000 is their most environmentally friendly gas boiler to date, which is a big claim ...but here's why:
This boiler comes in a range of outputs, which means you can choose the most appropriate level of power for your home. This ensures you don't waste money burning more fuel in a boiler that's too big for your needs.
An exciting new feature, known as 'Quick Tap' lets you indicate to your boiler (with one quick flick of the hot tap, on then off) that you want hot water – then when you go back to the tap a second time, the hot water is instant. This is a really interesting way of preventing water waste and also avoids that irritating wait for water to get hot on the chilliest of days.
Worcester Bosch has stated that their entire gas boiler range is capable of running on a 20% hydrogen blend. Hydrogen fuel is still in development, but this is a great step in future proofing this unit for a time when natural gas may be phased out as a fuel source. You can find out more about hydrogen gas in our guide to hydrogen boilers. If you to know more about the gas boiler ban, visit our ‘when are gas boilers being phased out?’ guide.
Other plus points:
It's 'Quiet Mark' awarded – meaning it's one of the quietest gas boilers you can get
Wireless controls (with Bosch's 'EasyControl')
Its packaging is 99.9% recyclable
The system boiler is compatible with solar panels, for additional energy savings and reduced environmental impact
Types Available
Combi
System
Outputs
25kW, 30kW
12kW – 24kW
Efficiency Rating
A-rated (CH, DHW*)
A-rated
Warranty
Up to 10 years**
Up to 10 years**
*CH: Central Heating, DHW: Domestic Hot Water
**When fitted by Worcester Accredited Installer
Potential Cost: £1,060 – £1,410 (excl. installation)
Types Available: Combi, System, Regular (Conventional/Open Vent)
Home Sizes: Small – Large
Ranking second in our home heating survey, Vaillant is another highly popular choice amongst engineers and homeowners.
EcoTec Plus is the flagship model for Vaillant and they can boast some incredible tech inside these highly efficient boilers.
By learning when you don't use it as much, this gas boiler can drop to 16% of its power to save fuel – and your pennies, win-win!
Vaillant claims they always aim for low energy consumption, high performance and ease of use, which we can see in the following features:
A-rated for hot water and heating efficiency
Hot water within 5 seconds
Simple backlit display
Quiet Mark awarded
Vaillant are currently testing all of their boilers to confirm compatibility with a 20% hydrogen blend. This is a good indication that these boilers may soon be secure for any possible gas supply changes.
Types Available
Combi
System
Regular (Conventional)
Outputs
25kW – 38kW
12kW – 37kW
12kW – 35kW
Efficiency Rating
A-rated (CH, DHW*)
A-rated
A-rated
Warranty
5 – 10 Years**
5 – 10 Years**
5 – 10 Years**
*CH: Central Heating, DHW: Domestic Hot Water
**Warranty may extend up to 10 years if a Vaillant Advance installer is used
Potential Cost: £1,200 – £1,400 (excl. installation)
Types Available: Combi, System
Home Sizes: Small – Large
Part of Ideal's premium range, the Vogue Max is made to be long lasting, stylish and reliable.
This gas boiler has a number of features similar to its companions in this list, but it does offer a few extras that make it stand out.
Ideal have designed their own magnetic system filter which comes with the boiler. This is a great tool that sits within your pipework and filters out all the impurities from your water. This can help to extend the life of the boiler, improve efficiency and reduce running costs. This filter also comes with a 10-year warranty, so it's a great bonus to the whole set-up.
Other noteworthy features:
Extensive 12-year warranty offer, including parts and labour
Lightweight design for quick and easy installation
Compact cupboard fit
Ready to run on 20% hydrogen blend
Types Available
Combi
System
Outputs
26kW – 40kW
15kW – 26kW
Efficiency Rating
A-rated (CH, DHW*)
A-rated
Warranty
10 – 12 years**
10 – 12 years**
*CH: Central Heating, DHW: Domestic Hot Water
**12 year when installed and serviced by a Max accredited installer (other terms may apply)
Potential Cost: £900 – £1,200 (excl. installation)
Types Available: Combi, System, Regular (Conventional)
Home Sizes: Small – Large
Released in 2019, the Baxi 800 range was created with the aim of providing an efficient and reliable gas boiler that would last.
This boiler also includes a magnetic filter, so users can feel confident their pipework is protected and maintenance issues will be kept at bay.
With the range available in combi, system and regular versions, all sizes of home can benefit from what this boiler has to offer.
Highlights:
10-year warranty which includes parts and labour
Adey Micro2 magnetic system filter to protect the heating system and boiler
Compact design allows for installation within a kitchen cupboard
20% hydrogen ready
Types Available
Combi
System
Regular (Conventional)
Outputs
25kW – 36kW
12kW – 37kW
12kW – 35kW
Efficiency Rating
A-rated (CH, DHW*)
A-rated
A-rated
Warranty
10 years**
10 years**
10 years**
*CH: Central Heating, DHW: Domestic Hot Water
**Terms apply
Potential Cost: £1,190 – £1,550 (excl. installation)
Types Available: Combi, System
Home Sizes: Small – Large
Viessmann is another manufacturer with a great reputation. They are only the second brand of gas boiler to be given a 'Which? Best Buy' for 2021.
They rate highly for reliability and customer satisfaction and the 200-W model is perhaps the smartest gas boiler on our list.
This intelligent boiler has wifi capability which allows users to control everything via an app, making it highly convenient.
Viessmann can also boast that this model has a 98% efficiency capability – that's incredibly high! Making it one of the most energy-efficient gas boilers you can get. Great for the environment and your savings.
Other features:
Viessmann's 'MatriX' cylinder burner improves energy efficiency, keeps the boiler healthier for longer and reduces environmental impact
Colour touchscreen
Quiet operation
12-year warranty available
Hydrogen ready
Types Available
Combi
System
Outputs
25kW – 32kW
11kW – 32kW
Efficiency Rating
A-rated (CH, DHW*)
A-rated
Warranty
10 – 12 years**
10 – 12 years**
*CH: Central Heating, DHW: Domestic Hot Water
**Terms apply
Out of the 5 best boilers we have reviewed in this article, any one of these boilers could be determined as the best depending on factors like price, warranty, product range, and your specific heating needs.
Product range: Baxi 800 & Vaillant ecoTec Plus
Price: Baxi 800
Warranty: Ideal Vogue Max & Viessmann Vitodens 200-W
Eco-friendliness: Worcester Bosch Greenstar 4000
Deciding on the type and size of the boiler you’ll need will also help you choose between these brands. We recommend that you seek professional advice from a heating engineer to help with this.
Get the best gas boiler price
We hope these 5 fab boilers have given you some insight into what is available in the world of gas boilers, and what features are important to you. The next step you need to consider is how to get your new boiler at the best possible price.
Whilst boiler pricing can be straightforward, the cost of the installation can differ depending on a number of factors: How straightforward a replacement will be, if the boiler is to move position, if new pipework is needed, etc. That's why we always recommend comparing at least 3 quotes from qualified heating engineers. This gives you an idea of which quotes are more affordable and ensures you'll get the very best deal on the installation of your new boiler.
Here at Boiler Guide we find the engineers, so you don't have to. Simply fill in our quick online form and we will find up to 3 qualified installers in your local area who can provide you with free, no-obligation quotes.
You can then compare high quality installers and have peace of mind that you're finding the best deal available. Click the button below to get your free quotes now.
Worcester Bosch is one of the most reliable boiler brands as it offers warranties of up to 12 years. This, alongside the positive reviews from customers, shows the confidence in the quality of the product.
Which is the best gas boiler in the UK?
The Worcester Bosch Greenstar takes the crown for best boiler and has also been given the "Which? Best Buy" award. This boiler is consistently highly rated for its reliability and quality.
What is the most efficient gas combi boiler?
The Vaillant ecoTec Plus and Viessmann Vitodens 200-W are two of the most efficient gas combi boilers on the market, with efficiency ratings of 94%. Having an efficient boiler will help keep your heating bills as low as possible.
What is the best regular gas boiler?
The Vaillant EcoTec Plus is the number one rated regular gas boiler from our home heating survey. It’s highly rated by both engineers and homeowners for its reliable technology and efficiency.
