Best combi boilers, gas boilers and oil boilers

Choosing the best type of boiler for you

Your main decision when buying a new boiler is whether to buy a combi boiler, which provides heat for your radiators and domestic hot water on demand, or a heat-only boiler, which is connected to a hot water storage system. Ask your chosen installer which type is best for your home.

Most new boilers are gas condensing boilers, which are far more energy-efficient than traditional boilers. More than 1.5 million homes in the UK use oil for their heating, however, but your heating bills with an oil boilers could cost twice as much as they would with a gas condensing boiler.

Our expert guide on how to buy the best boiler can help you choose which boiler to go for. 

• Which? Best Buy boilers
• Boiler features explained
• Condensing boilers explained
• How to buy the best boiler

Getting a boiler installed

Any new boiler must be installed by a registered installer. For gas condensing boilers, this would be anyone listed on the Gas Safe register. Installation costs will vary enormously depending on how much work is required, but we have some boiler installation examples to help you figure out how much you can expect to pay for boiler installation.

Some gas companies have agreements with manufacturers to provide new boilers for their customers, so they're more likely to recommend a boiler for you than make it easy for you to choose your own. If you prefer to get a Which? Best Buy boiler, contact the manufacturer to get a list of local installers for their boilers.

• Boiler installation
• Buying a boiler

Which are the best boiler brands?

Buying a new boiler is expensive and can be intimidating. The cost of the boiler is often eclipsed by the price of installation – plus there are safety issues to consider – so it’s crucial that you make the right choice for both the boiler and the installation service.

To help you choose a boiler, we rate the best combi boiler brands, including Worcester Bosch, Baxi, Vaillant and British Gas, by asking nearly 3,000 owners about their experiences with their boilers.

• Gas condensing boiler brands rated

Save money with a new boiler

Central heating costs, particularly during the colder winter months, make up a large chunk or your household bills. You can keep heating costs down by making smart heating choices – a modern condensing boiler could save you up to £195 a year in heating costs. 

All the Which? Best Buy boilers perform well for efficiency. But being more efficient with your boiler doesn't just stop at the type of boiler you choose – there are other easy ways to cut your heating bills. 

• Boiler efficiency tips
• Compare boiler energy use
• Video guide to maintaining your boiler

Getting your boiler serviced

It's a good idea to get your boiler serviced every year to make sure it stays in good working order. Watch your boiler service video guide to find out what good boiler service should include, check our guide to the cost of replacement boiler parts, and find out if it's worth getting boiler breakdown cover with our boiler servicing contract reviews. 

We also surveyed Which? members to find out how satisfied they were with boiler services and boiler repairs they'd had carried out, and our recent undercover investigation into boiler repairs found some boiler servicing engineers were so bad that we reported them to the safety watchdog.

• Getting a good boiler service
• Boiler servicing contracts
• Boiler services and boiler repairs