New boilers

Uswitch services are provided at no cost to you, but we may receive a commission from the companies we refer you to. Products in this table are ranked based on deals that are proving to be popular with our customers, that are competitive in the market and have a smooth buying process.

Save up to £840* when upgrading from G to A

It pays to have a more efficient boiler.

Waste less energy
Save more money
Manage your bills more easily

Why does boiler efficiency matter?

A boiler's efficiency relates to the amount of energy it uses when it comes to heating water.

For example, if 95% of the energy used heats the water, this means that 5% is lost, which would represent an energy-efficient boiler. However, a boiler that loses 40% of its energy would not be very energy-efficient.

Considering that you pay for 100% of the energy used regardless of how much is wasted, it's wise to ensure your boiler is as energy-efficient as possible.

What do boiler efficiency ratings mean?

Boilers are either rated according to the ErP or SEDBUK systems.

ErP is the European rating system for boilers, rating their efficiency from A to G. All UK modern gas boilers are legally obligated to be A-rated - i.e. as efficient as it's possible to be.

SEDBUK is basically the same rating system but it adds exact percentage scores to each boiler for extra detail.

What factors are most important to consider when buying a new boiler?

When buying a new boiler, think about the following:

Boiler type

15% of homes are not connected to the UK's gas network and will need to use an alternative method of heating, such as a wood-burning stove, but the rest of the country will be looking at a gas boiler. There are three main types of gas boiler: combi (best for smaller homes), heat-only (best for homes that use a lot of water in different rooms at the same time) or system (best for bigger homes with poor water pressure). Our boilers statistics page breaks down the average cost per type of boiler installed in the UK.

Boiler size

This is important in terms of the physical size of the boiler and the space it needs to fit into, but also in terms of its power in kW. The general rule of thumb for boilers is that the more heat you need (including to heat water), the higher kW boiler you'll need.

Boiler reliability

While buying a new boiler is expensive, any repairs that need to be carried out on it are also typically expensive, so it's important to try and pick a boiler with solid reliability.

Boiler type

Boiler size

Boiler reliability

While buying a new boiler is expensive, any repairs that need to be carried out on it are also typically expensive, so it's important to try and pick a boiler with solid reliability.

Still not sure what's best for you? Take a look at our boiler guides

GUIDE

Boiler FAQs

As a ballpark figure, a new boiler installation might take about 4-6 hours or a couple of days. The time varies depending on the type of boiler and any complications that might mean more time has to be taken during the process. This could include moving the boiler to a different location; converting from one type of boiler to another; or any gas safety issues that might be uncovered and require dealing with.

* Estimated saving for a gas-heated detached house in England, Scotland and Wales, when replacing an old G-rated gas boiler, programmer and room thermostat with a new A-rated condensing boiler, programmer, room thermostat and thermostatic radiator controls (TRVs). Savings will vary depending on the size and thermal performance of your home. Source: https://energysavingtrust.org.uk/advice/boilers/

Heatable Terms and Conditions

¹ Exclusive 12 year manufacturer backed warranty available across all Viessmann 100-W boilers. Warranty is registered by Heatable Ltd and upheld by Viessmann UK.

² 0% APR is available on selected boiler packages. Heatable are a credit broker and not a lender – offering lending services through a panel of lenders. Finance terms under Ordering point 6 at https://heatable.co.uk/terms

³ Next day installations are subject to engineer availability in a customer’s location within the UK and the type of installation being undertaken.

⁴ TrustPilot rating accurate as of 17/04/2023. https://uk.trustpilot.com/review/heatable.co.uk

⁵ £100 Uswitch discount is applicable to all orders and must be claimed during the booking process using the ‘USWITCH100’ code. This code cannot be used in conjunction with, or in addition to any other codes or promotions. Code cannot be retrospectively claimed after an installation has been undertaken.

⁶ Every Uswitch customer order will be supplied with a free CO2 detector. Products will be in accordance with British standards BSEN50291. CO2 detector manufacturers will vary based upon availability and cannot be chosen. Detectors cannot be removed from an order, replaced with an alternative product or exchanged for cash value.

BOXT Terms and Conditions

‡ Click to see BOXT Terms and Conditions, Financing information, Warranty information, Trustpilot reviews and the BOXT Price promise.

iHeat Terms and Conditions

¹ All boilers come with a manufacturer-backed warranty ranging from 6 to 12 years.

² 0% APR available on select boiler packages. iHeat are a credit broker and not a lender.

³ Next-day installation availability depends on your location and the type of installation. Orders must be placed before 3pm, Monday - Thursday, excluding bank holidays. For further information on our installation terms please see https://iheat.co.uk/terms.

⁴ £75 off discount is valid for all orders and must be redeemed by using the code "USWITCH75" during the booking process. This code cannot be used together with any other codes or promotions. Please note that the code cannot be claimed after the installation has been completed.

⁵ TrustPilot rating is accurate as of 26/01/2023. You can find more information on TrustPilot. https://uk.trustpilot.com/review/iheat.co.uk

British Gas Terms and Conditions

¹ British Gas acts as a credit broker, not the lender and offers products from a panel of lenders. Payment options are subject to change without notice. British Gas is a trading name of British Gas New Heating Limited (No. 06723244), an appointed representative of British Gas Services Limited (No. 03141243) which is authorised and regulated by the Financial Conduct Authority (Financial Services Register No. 490568). Both companies registered in England and Wales. Registered office: Millstream, Maidenhead Road, Windsor, Berkshire SL4 5GD. Availability of credit depends on status and credit checks. Terms and Exclusions apply.

HomeServe Terms and Conditions

HomeServe Membership Limited (CRN: 002770612, registered office address: Cable Drive, Walsall WS2 7BN) (“Homeserve”) brings you this discount offer from Help Link UK Limited (CRN: 03527087, registered office address: 1175 Century Way, Thorpe Park, Leeds, England, LS15 8ZB) (“Help-Link”). Help-Link is part of the HomeServe group of companies.

¹ Worcester Bosch and Vaillant. Warranty extension from 5 years to 10 years available on Ideal Logic boilers. All warranty extensions are subject to an additional charge. 5 year manufacturer warranty not available on Ideal Mexico boilers, which come with a 2 year warranty. 10 year warranty extensions are not available on Ideal Mexico or Keston boilers.

² HomeServe Membership Limited is a credit broker, not a lender. Creation Consumer Finance acts as the lender. If you choose a credit option, Help-Link UK Limited trading as HomeServe may receive commission from Creation Consumer Finance which is a fixed percentage of the total loan amount. For more information, contact Help-Link UK Limited. BNP Paribas Personal Finance is a trading style of Creation Consumer Finance Limited. Registration Number: NI032565. Registered Office: 4th – 6th Floor, Wellington Buildings, 2-4 Wellington Street, Belfast, BT1 6HT. Creation Consumer Finance Limited is authorised and regulated by the Financial Conduct Authority. The approval of your application depends on your financial circumstances and borrowing history, so do the terms you may be offered. Access to finance is not guaranteed and credit is subject to status, affordability assessment and credit checks. Minimum spend and eligibility criteria applies.

³ TrustPilot rating accurate as of 17/03/2023. https://uk.trustpilot.com/review/www.homeserveboilers.com

⁴ The £100 discount is only available to Uswitch customers. Only one discount available per boiler installation on all gas boilers provided by HomeServe. Installation must be booked within 30 days from the date that the boiler quote is accepted. No cash alternative will be given. The discount will remain available as long as the quote is valid. This discount cannot be used in conjunction with, or in addition to any other discount or promotion. HomeServe reserves the right to withdraw the discount at any time.

New boilers

Save up to £840* per year and increase your home's energy efficiency by installing a new boiler

Get what you need with these reliable boiler brands

Uswitch only works with trusted suppliers

Save up to £840* when upgrading from G to A

Why does boiler efficiency matter?

What do boiler efficiency ratings mean?

What factors are most important to consider when buying a new boiler?

Boiler type

Boiler size

Boiler reliability

Boiler type

Boiler size

Boiler reliability

Still not sure what's best for you? Take a look at our boiler guides

Which boiler is best for your home?

What's the cost of a new boiler?

10 tips that could save your life

Boiler maintenance guide

What are the different types of boilers?

When is it time to call the experts?

Boiler FAQs