We use cookies to allow us and selected partners to improve your experience and our advertising. By continuing to browse you consent to our use of cookies as per our policy which also explains how to change your preferences.

Home Heating Systems

Gas Central Heating

By Ellie Simmonds

Article 2 of 8

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

Gas Central Heating

Learn more about gas central heating systems and gas boilers, including the average costs per year - so you can find out if you're paying too much.

Most households in the UK have mains gas central heating. Find out if you're paying too much for gas and learn more about the pros and cons of gas central heating.

Gas central heating is a so-called ‘wet system’, which means a gas-fired boiler heats water to provide central heating through radiators and hot water through the taps in your home.

Some houses that aren’t connected to the gas network can use electrical heating, liquid petroleum gas (LPG) or heating oil, which work in a similar way to gas central heating. LPG and oil are delivered by road and stored in a tank, which you may have to buy or rent from your supplier.

Annual average cost of gas

The average annual cost for heating and hot water using gas in the UK is £548 when consuming around 12,000 kWh a year*. 

Remember, this cost is just a guide to help you compare costs of different types of fuel. There are a number of factors that affect energy bills, including the age of your home and insulation, the efficiency of a hot water and heating system, and where you are in the UK.

£548The annual cost of heating and hot water using gas.

If you're worried about your energy bills, it's worth seeing whether you're on the right energy tariff for you by using our free energy switching service, Which? Switch. Click to compare gas prices.

Pros of gas central heating

Gas is a highly efficient fuel, so you get a good return on every unit of energy. Modern condensing boilers, which use hot flue gases that are wasted in a standard boiler, have very high efficiency. Some are now 90% or more efficient.

Gas is piped directly to your home, so you don’t need to store any fuel.

Replacing a standard gas boiler with a highly efficient modern condensing boiler is relatively straightforward. To find out which boiler brands are the most reliable, as rated by boiler owners and heating engineers, see our Best Buy boilers.

As gas is the most widely used heating fuel in the UK, finding a heating engineer on the Gas Safe Register scheme should be fairly easy if your boiler breaks down or needs servicing. 

Anyone proposing to carry out work on your boiler is required by law to be on the Gas Safe Register. You can check an engineer or firm's registration on the Gas Safe Register website or by calling directly on 0800 408 5500.

Compare and switch suppliers

Choose the fuel type
to compare:

Gas and electricity Electricity
Gas only

You can find details of trustworthy, local heating engineers by visiting Which? Trusted Traders.  

Cons of gas central heating

The UK is no longer self-sufficient in gas and must compete with growing demand from other countries.

As a fossil fuel, gas produces carbon dioxide when it’s burned and can’t be considered a clean source of energy.

Installing a gas central heating system from scratch can be expensive and disruptive. If you’re not on the gas network, connecting your property can also be costly.

Gas boilers can be serviced annually to ensure they run efficiently and last as long as they should do. 

Can installing a cosy wood burning stove help cut your gas central heating costs? To find out, see our guide to wood burning stove costs and savings

*(The estimated cost of heating and hot water using gas is calculated using the average annual heat demand for a medium user (12,000 kWh), as calculated by Ofgem, and the price per kWh for gas, calculated by Which? in Oct 2017.)