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. You can understand more and change your cookies preferences here.

Home & garden.

Updated: 3 Dec 2021

British Gas

British Gas is the UK’s largest domestic energy firm, supplying around a quarter of homes in Great Britain with gas. But is the biggest also the best energy supplier?
Sarah Ingrams
British gas big six 480402

As its name suggests, British Gas is British owned and based. It's still the biggest energy company in the UK, and says it services nine million homes, although it has been losing customers for a while, including close to 300,000 in 2019.

It's a subsidiary of Centrica, a multinational energy and services company, which also owns utility suppliers in the Republic of Ireland and North America.

It's known as Scottish Gas in Scotland and claims to be ‘bringing Britain the smooth-running homes of today and tomorrow’. As well as gas and electricity, it also sells boilers, smart home products from the Hive brand and HomeCare insurance.

Its British Gas Rewards scheme gives customers personalised offers, which can include films on Sky, days out at UK attractions, O2 show tickets, Wilbur the Penguin toys and discounts on restaurant meals and days out.

It has taken on customers of Robin Hood Energy, People's Energy and other smaller firms when they stopped trading.

Can British Gas save you money? Use our independent switching site, Which? Switch, to compare gas and electricity prices and find out.

British Gas smart meter energy monitor

British Gas customer score

British Gas came joint 18th out of 25 energy companies, as rated by 7,460 members of the public, in the annual Which? customer survey – the biggest independent view of energy suppliers. It was joint with prepayment-focused supplier Boost.

Customers gave it OK ratings for many aspects of its service, although they don’t consider it good value for money, but do think its customer service is better than some similarly-ranked firms.

So far it has been quite good.

British Gas customer

I think it's probably more expensive than some providers but I trust it.

British Gas customer

British Gas score breakdown 

The graphic below shows the breakdown of British Gas’s score from our survey.

Scroll down to read our full verdict on British Gas, plus how its electricity fuel mix compares with the average across the country.

Find out how British Gas compares with other energy companies – click to see our full results of the best and worst energy companies.

Which? verdict on British Gas

Although it remains the largest energy supplier in Britain, British Gas is still neither the best loved nor the cheapest. Customers continue to leave it in their thousands, suggesting they’re looking for better service or prices elsewhere.

Customers consider it poor value for money – although it was among five suppliers to receive this rating and another three were considered worse value for money. It does sometimes offer cheaper fixed deals, but its out-of-contract variable tariff has consistently been in line with the maximum permitted by Ofgem’s price cap. Most of the biggest suppliers charge the same for their out-of-contract tariff, however.

Switching away from a tariff at the level of the price cap to one of the cheaper deals available can consistently save a household using a medium amount of gas and electricity £200 per year, according to our research.

British Gas offers tariffs including a 'green future' tariff (matching your electricity use with renewables, 6% or your gas use with biogas and offsetting the carbon footprint of the rest of your gas use), a tariff designed exclusively for Electric Vehicle drivers (with cheaper energy for five hours overnight to charge your car) or with boiler cover included. Some of its tariffs have exit fees of £30 per fuel if you want to leave before the end of the fixed term.

British gas van and engineer

Some British Gas customers have stuck with it since privatisation. Our survey found that 44% of British Gas customers have been with it for five years or more. Some 18% of the British Gas customers in our survey said they had been with it for more than 20 years.

But loyalty doesn’t equate to high satisfaction levels and British Gas customers' feedback gave it three stars out of five for customer service. While no firms achieved the full five stars this year, just one firm gained a lower rating for its customer service.

It's accurate at billing just as my smart meter reads.

British Gas customer

British Gas’ highest customer rating was for the accuracy of its bills, for which it achieved a good four-star rating. Overall, 80% of its customers in our survey said they considered the accuracy of its bills 'good' or 'excellent'.

While this is close to the average across suppliers (78%), the best firms had more than 85% of customers rating their bills high for accuracy.

British Gas' customers found its bills slightly less clear than some others, resulting in a three-star rating for how easy its bills are to understand. Around half of the energy firms included in our survey scored the same.

I understand most of each bill but some of the technical terms are beyond me.

British Gas customer

The weakest area for British Gas was value for money, according to customers in our survey. It was one of five firms to score just two stars for value for money. The top-scoring firm managed five stars. But British Gas wasn't the worst for value - three firms were rated one staron this measure.

Quite expensive compared to other providers.

British Gas customer

British Gas' customer service is ok, but not excellent. Its three-star ratings for both customer service and complaints handling put it on a par with many other large suppliers, but lagging behind the highest-rated brands.

British Gas branded van

According to official data, British Gas received six complaints per 1,000 customers in spring last year. This is half the number received by some other big firms – such as Npower and Scottish Power –  though it resolved less than 90% of them within eight weeks.

Our snapshot investigation into energy companies' customer waiting times in September and October 2020 found it took 23 minutes 32 seconds, on average, to get through to a human in British Gas’s customer services. 

This was the second longest median average wait time across 31 firms we called. The average time across all firms was just under 6 minutes, with several answering in less than 2 minutes.

When we tested British Gas’s live chat, it took 10 minutes 47 seconds on average to respond to us, making it the third-slowest firm included to respond. The average wait time for the 18 firms with live chat that we contacted was just over 3 minutes.

British Gas has installed the most smart meters of any supplier, and the most second-generation models. It has an app which lets customers send meter readings, pay bills, set budgets and book repair appointments. It also owns Hive and sells its smart thermostats, smart plugs, smart light bulbs and smart locks.

Pros: Has accurate bills according to customers.

Cons: Rated poor value for money by customers; one of the slowest to respond by phone and on live chat in our investigation.

Can you join British Gas with a prepayment meter?

Yes. British Gas pay-as-you-go customers can top-up at a Post Office or Payzone outlet. in January 2020, British Gas increased its minimum top-up to £5 but this is changing back to £1 again.

It's installing smart prepayment meters. Customers who have them can top-up using the British Gas website, its app or an automated payment phone line.

British Gas offers £5 emergency credit for when you run out of energy but can't top-up. Friendly emergency credit is activated automatically if you run out of credit between 6pm and 9am, on a Sunday or bank holiday. You can also activate emergency credit at other times via your smart meter, in-home display or using your key or card with a traditional meter.

Any energy you use will be recorded as debt on your meter and you'll pay it back next time you top-up. 

Does British Gas sell renewable energy?

British Gas generates some of the renewable electricity it sells, buys some directly from generators and buys certificates to match the remainder of its customers’ use.

Proportion of renewable electricity sold to domestic customers
Generates renewable electricity?
Buys renewable electricity directly from generators?
Proportion of customers’ renewable electricity matched by REGO certificates?
Generates or buys directly from fossil fuels?
Sells green gas?
75%Yes (14.6%)Yes (15%)14.6%, and 63.6% backed by GoOsNoYes (0.02%)

Proportion of renewable electricity according to British Gas’s 2020/21 fuel mix. Other responses based on information provided by suppliers in August and September 2021.

Overall British Gas’ electricity fuel mix is 75% renewable and 25% nuclear (from its share in EDF Energy’s nuclear plants). 

It generates around 4,000MW of renewable power each year, mainly from wind (50%) and biomass/ biogas (46%) and a smaller amount of solar power (4%). It has offshore wind generation in the north sea and onshore wind in Scotland.

British Gas matches 14.6% of its domestic customers’ use with this and has contracts to buy another 15% directly from generators. This doesn’t match every customer’s use though – nearly two thirds of its electricity is matched with renewable power generated outside the UK, in Europe, using Guarantees of Origin (GoOs).

Customers who buy British Gas’ Green Future Tariff will have their electricity use matched with renewable sources of generation in the UK.

Find out more about the differences between energy companies’ renewable electricity.

British Gas in the news

British Gas in 2021

December: British Gas announced that its newer brand, British Gas Evolve, was changing its name to British Gas. 

Nothing is set to change for customers besides the name. See what British Gas Evolve customers need to know.

November: British Gas became the new supplier for Bluegreen Energy, Neon Reef, Social Energy and Zebra Power customers when the smaller firms stopped trading.

September: Customers of MoneyPlus Energy, People's Energy and PFP Energy were moved to British Gas after the smaller suppliers stopped trading. In total, around 441,000 customers moved to British Gas.

April: British Gas will begin supplying gas and electricity to Nabuh Energy's 36,000 customers after it bought the smaller brand.

March: British Gas is paying 141,415 of its customers over £1.2m after overcharging them when they switched supplier or tariff between 2013 and 2020. It was one of 18 energy firms found by regulator Ofgem to have failed to uphold these rules. Over 1 million customers were affected.

Affected customers will receive £8.97 each, on average, reimbursing them and paying some compensation.

British Gas in 2020

September: British Gas has acquired Robin Hood Energy and all the energy companies on its network, including Ebico. 

August: British Gas paid out £1.48m to around 270,000 prepayment customers for failing to tell them when it changed their top-up provider on 1 January 2020, energy regulator Ofgem announced. 

Some customers may not have had electricity or gas supply during cold weather as a result and they couldn’t phone British Gas on 1 January as its general enquiries line was closed. 

British Gas in 2019

December: Breeze Energy customers were transferred to British Gas after it was chosen to take on customers of the smaller failed supplier. 

April: British Gas and Sainsbury's ended their partnership, which begun in 2011.