Gas fire versus central heating – what’s the cheapest way to warm up your living room?

With energy bills high and temperatures dropping, we're looking at a gas fire versus central heating to see which one works out cheaper at keeping you warm at home. 

As the nights get longer and temperatures fall, families can expect to spend more time at home, especially in the evenings. If you’re lucky enough to have a gas fire in your living room, you’ll be wondering whether it’s cheaper to put it on or use your central heating.

But gas and electricity are still expensive and families are still worried about how much their energy bills will cost, even though the energy price cap dropped in October.

Goodto.com's Money Editor Sarah Handley says: "As we head into winter, we'll all be using more energy to stay warm, but more than ever before, we should be thinking about how we can keep warm in the most cost-effective way possible.

"It's also important that you make sure you understand your energy bill so you can make sure it's correct and also have a clear picture of how much energy you use." Check out our handy guide if you need your energy bills explained.

Gas fire versus central heating – which is cheaper to heat your living room? 

To heat your living room, and only your living room, it's actually cheaper to use your central heating rather than your gas fire. In general, gas fires are less energy efficient than modern boilers, but working out whether a gas fire or central heating is the cheapest way to heat a single room isn’t particularly straightforward. 

Richard O’Connor, strategic marketing director at workplace product supplier FirstMats, says: “Depending on the room size and if you have high ceilings or an open-plan property, gas fires usually won’t be efficient to heat a single room.

“If you have an up-to-date central heating system you will have temperature controls on your radiators and an electric thermostat, allowing you to control the heating of each room in your home more efficiently and cost-effectively than a gas fireplace. If you have a modern boiler, this is cheaper still.”

If you're surprised that it's cheaper to use your central heating  than a gas fire, it's worthwhile checking out these other cheap heating myths that could end up costing you money. 

How much does central heating cost?

Central heating costs depend on several factors. These include:

•  what type of boiler you have 
•  how efficient your boiler is 
•  how big your home is 
•  whether you can adjust individual radiators .

Director of Technical Services at Worcester Bosch, Martyn Bridges, says: “It is very difficult to give an average cost of heating a home as there are many variables that come into play when making these calculations (outside air temperature, how warm the householder wants their house to be etc.).

 “The trade association OFTEC publishes regular reports on the average heating costs both on a regional basis and also comparing different heating fuels." The latest report, published in July 2023, lists the following estimated annual costs for a pre-1980, semi-detached three-bedroom home in the Midlands as:

• For homes with a condensing gas-fired boiler, the estimated annual cost is £1,800
• If you have a condensing oil-fired boiler, you'll pay an estimated £1,250 per year
• Those with an air source heat pump, will pay roughly £3,100
• Homes with electric panel heaters will pay about £3,400 each year.

“These estimates do not include any allowance for hot water production and are based on an annual heating requirement of 16,000kWh,” Martyn adds.

How much do gas fires cost to run?

A gas fire will cost between 21p and 49p to run per hour. But the actual cost will depend on how much power your gas fire uses, how often you use it and how much you pay for your gas. 

Gas fires usually require 3kW to 7kW of power and 7p is the maximum unit cost energy suppliers can charge for gas under the current energy price cap.

We can work out how much a gas fire costs to run per hour by carrying out a simple calculation: Divide the fire’s power by 1,000 to get kiloWatt hours, then multiply this figure by the unit cost for gas.

For example, for a 5,000W gas fire: 5000/1000 = 5kWh, multiply that by 7p which equals a cost of 35p/hour.

 Is central heating cheaper than a gas fire? 

For most people, using central heating to just heat one room will work out cheaper than using a gas fireplace in that room. This is because boilers tend to be much more efficient than gas fires. But it only works out cheaper if you turn down the radiators in the other rooms, using individual radiator valves or smart controls.

Technical manager at home heating expert Alpha, Darran Smith, says: “Keep doors closed on less frequently used rooms and hallways, making sure the main heated spaces are only those areas you frequently use. 

“Even bedrooms don’t need to be kept heated all the time and often a reduced temperature is preferred for sleeping.”

How to tell which is cheaper for your home

The best way to work out which is cheaper for your home – a gas fire or radiator powered by central heating – is to try out both options and compare costs. If you have a smart meter, you’ll normally be able to see your energy use and costs via your online account.

So, on day one, turn off your central heating and just use the gas fire to heat your living room. On day two, turn off the gas fire and the radiators in the other rooms and use your central heating to heat your living room. 

Assuming all other factors are equal, you can then compare how much gas you used on each day and find out the cheapest option.

 How much is gas right now – is it expensive? 

The price per unit of gas is currently capped at 7p under the energy price cap, but this can go up or down depending on the wholesale price of gas. There are many complex reasons why energy bills have gone up a lot since early 2022, mostly due to Russia’s invasion of Ukraine, but there were supply issues before this too, partly down to the world coming out of lockdown.  

What can I do to cut the cost of central heating or a gas fire over winter? 

Whether you use central heating or a gas fireplace to heat your living room, there are several things you can do to keep it warm and stop any unnecessary heat loss.  

1. Use heating controls

Joanna O’Loan, knowledge manager at the Energy Saving Trust, says: “Installing and correctly using a full set of heating controls, including a thermostat, programmer and thermostatic radiator valves will help you manage your heating and avoid wasting energy.” 

2. Install thermal blinds or curtains

Thermal blinds or curtains are designed to keep the heat in during the winter months, while also providing an easy way of upgrading home decor. 

Oliver Hudson, managing director at BlindsbyPost, says: "Thermal blinds offer a cost-effective solution for reducing heat loss from windows, which means reducing your energy bills."

When the summer months come around, they can also be helpful in keeping rooms cool too. 

3. Turn the thermostat down

According to research by Alpha, most Brits prefer their homes to be heated to about 20 ºC – but you can save money by reducing your room temperature by just 1ºC, which will save more than £100 a year on your heating bill. It also helps to know how many hours a day your heating should be on, so you don't have it on more than you need.

You could also try out this radiator hack that helped Goodto.com's Money Editor cut her energy usage by 20%!

Sarah Handley

Sarah is Goodto.com’s Money Editor, covering everything from the energy price cap, cost of living payments and food prices to major sales, money saving tips and how to get more for less. A writer, journalist and editor with more than 15 years' experience, Sarah’s allergic to confusing jargon and her biggest pet peeve is a money-saving hack that doesn't actually save you money.