Gas or electricity: Which is cheaper?

It’s a question many of us ask and an important one if you are in a position where you need to decide how to heat your home.

If we look at cost alone, gas is around 3-4 times cheaper than electricity per unit. One unit of gas costs around 4p per kWh. By comparison, one unit of electricity is closer to 15p per kWh. So if we compare just the unit price, gas is considerably cheaper.

However, there are several other factors to consider that make the comparison of the two energy options more complicated.

  • Gas boilers are not as efficient as electric heating systems

Even the newest gas boilers are not as efficient as electric heaters. For example, when you heat your home using electricity, 1 kWh of electricity generates exactly that in heat. Whereas a new gas boiler will only be about 90% efficient in comparison.

  • Maintaining a gas boiler is more expensive.

Gas boilers are more costly to replace and repair when something goes wrong compared to the electric equivalent. Electric heating systems are around 50% cheaper to install and last twice as long as the average gas boiler.

Electric vs gas for heating: which is cheaper?

Heating generally is not cheap. So to answer this question, we have to consider which of the two systems is the most cost-effective in the longer term.

Initially, installing an electric system will be cheaper. However, over time, a gas system will generally be the more affordable way to heat your home. Just keep in mind the maintenance costs are often higher.

Gas is at least three times cheaper than electricity when it comes to heating a home. Gas systems are also renowned for heating a home faster and therefore meaning that you don’t need the system running for as long as an electric one to reach the temperature you desire. However, as mentioned above, gas heating systems are not 100% efficient. Even the best ones are around 90% which means you will use more gas units to heat your home. As the price is so much lower per unit though, you would still save money over electric heating.

Apart from the primary unit pricing of gas vs electricity, you should also factor in the cost of a yearly gas boiler service and the costs of maintenance and repairs. Traditionally if things go wrong with a gas heating system, they can be costly to repair. A new boiler will set you back £1000’s if a replacement is needed. By comparison, an electric system is less expensive to install and doesn’t require an annual service.

After measuring everything up, gas is still the cheapest way to heat a home. This is due to the low unit price, and even when you factor in a yearly service to keep your gas boiler working its best, it still comes out on top for heating your home.

Electric vs gas heating for hot water

Did you know that heating water accounts for 14-18% of your energy bill? It’s a considerable expense. So choosing whether to heat your water with gas or electricity is an important decision that could save or cost you money in the long run. As with the heating system, gas water heaters are less efficient than their electric counterparts.

Cost-wise, gas is cheaper than an electricity unit. So over a year, it will cost you considerably less to heat your water using gas over electricity, even with the added costs of servicing and maintenance. In addition, some heating engineers recommend that you keep an electric water heater running all day to ensure a good supply of hot water. This can prove hugely expensive over a year.

Heating water using a gas boiler is faster even if the gas supply is through an older, less efficient model. When you compare it to an electric system will still be considerably cheaper.

Electric vs gas for cooking

In most cases, a gas oven will allow for better efficiency and temperature control when cooking. By contrast, an electric alternative will heat an oven more evenly, which can be ideal for baking. In addition, electric ovens heat up slower. This means you’ll need to allow more cooking time which equals more electricity units used per meal. It is clear that once again the most cost-effective way to cook is using gas.

It’s possible to have the best of both worlds when cooking as long as you have a gas supply into your property. This can be achieved by using a built-in electric oven and a gas hob.

Which is more environmentally friendly?

The cost might not be the only consideration when choosing to heat your home with gas or electricity. The environmental impact each fuel source has is also an important consideration. Heating our homes is responsible for around 15% of the greenhouse gases released into the air in the UK. It’s the most significant single source of CO2 that comes from our household. So, choosing a green energy source is an important consideration.

The UK target is to reach net-zero carbon emissions by 2050. To support this, from 2025, new homes will no longer be installed with a gas boiler. So it’s clear that we need to look at environmentally friendly alternatives to heating our homes in the future.

Electricity is now the greenest fuel. This is due to the heavy investment over the last ten years in generating renewable energy. Wind and solar farms now feature across the UK landscape. These renewable energy farms provide a considerable amount of the electricity we use across the country. Although green gas generation is on the increase, the gas supplied into our homes predominantly still comes from fossil fuels. This means that, at least for now, electricity is the greener option.

Gas is the cleanest fossil fuel, but it’s still the UK’s most significant source of greenhouse gases. Heating your home using electricity still contributes to CO2 emissions. Since we use gas to generate about 40% of our electricity. However, we are now reaching a point where renewable electricity sources such as solar and wind generated as much electricity as gas in 2020. This means that if you pick an electricity tariff offering 100% renewable energy, your heating will be completely carbon-free.

What are the alternatives to gas and electric?

It’s no surprise that heating our homes is an expensive business. If your home does not have a connection to the grid or you’re just looking for an alternative way to heat your home, there are a handful of other options available:

Heat Pumps

A heat pump uses a minimal amount of electricity to absorb the natural heat from one space and release it to a warmer one. Think about how a fridge works and apply this in reverse. Instead of cooling an area, it will warm it up. A heat pump is very efficient and can produce up to 4 times more heat than electric heaters. In addition, they are reliable and can operate all year round.

The costs associated with the initial installation can be high. They can, however, make a lot of sense financially when you factor in the reduced energy bill.

Solar panels

An ecofriendly solar power will harness the sun’s energy to absorb heat in the solar collectors fitted to a roof. This heated fluid then transfers to your hot water tank, where it can be used.

Unfortunately, solar powers are not yet efficient enough to meet the demands of a typical household. This means soler use needs to be in conjunction with other heating methods. The initial costs can be high, as with heat pumps, but the return and savings make them a worthwhile investment.

Biomass boilers and stoves

A biomass system is essentially a domestic wood-fuel powered heating system that burns logs, woodchips or pellets. Biomass can also include food, animal and other industrial waste. A biomass stove can heat a single room. A biomass boiler is considered a direct replacement for a conventional gas boiler. Capable of heating your whole home and hot water. The process of burning wood and other matter emits around the same amount as a plant that is growing. This makes it a completely sustainable heating method. 

In conclusion, it’s clear when comparing purely cost that gas is the most cost-effective method of heating your home. However, electricity has the potential to be a greener, more sustainable method of heating for the future and there are certainly pros and cons to both.

The information contained in this article is provided for informational purposes only and should not be construed as advice on any matter. You should not rely on the information published in this article.


Hi, I'm Rob and I run I initially started this project 5 years ago when I was looking to switch energy suppliers and found there wasn't a website that provided simple, data backed reviews on all the suppliers available. Since then, I spent have a lot of time (too much some may say!) looking at all publicly available data about each supplier and writing reviews using this information. These reviews are updated as regularly as possible and any data is backed up by a source where necessary. I have also started writing guides on various energy related topics which hopefully you will find useful. If you find any issues, please use our contact form to let us know.

  1. One consideration, I’ve found in the past, is electric oil filled radiators. Can ‘spot’ heat certain areas/rooms, the oil holding the heat and the radiator automatically switching off and on to the desired level. Found keeping the gas heating on low to stop the place getting damp and using the oil radiator to heat areas I am in (picture temporary empty ground floor flat). Was using a key and card (pay money on to them instead of having a periodic bill, although the unit charge isn’t the same and usually slightly dearer) for the gas and electric payment at the time, which ever way round(before smart meters), so obviously directly saw the cost. There seems to be so many variables, it is difficult to find a concrete conclusion, but doing that cut the cost down dramatically. Any thoughts appreciated.

  2. hi
    thanks but why not have the comparison for cooking on a hob, seems to me that three quarters of the gas flame just heats the kitchen while with an electric hob it almost entirely heats the pan.

    can you tell me which is more efficient pls

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