British Gas

British Gas is the UK’s largest domestic energy firm, supplying more than a fifth of homes in Great Britain with gas. But just because it's the biggest does it mean it's the best?
Sarah IngramsPrincipal researcher & writer
British Gas logo besides a lit gas hob

As its name suggests, British Gas is British owned and based. It's still the biggest energy company in the UK and serves more than 8m homes and businesses.

The firm is a subsidiary of Centrica, a multinational energy and services company, which also owns utility suppliers in the Republic of Ireland. It's known as Scottish Gas in Scotland.

It also sells boilers, renewable heating, smart home products from the Hive brand and HomeCare insurance. Its PeakSave scheme gives some smart meter customers 50% off electricity between 11am and 4pm on Sundays. 

Use our tool to compare energy prices if you're looking for a new tariff.

British Gas score 

We combine the results of our customer survey with an in-depth assessment of companies’ behind-the-scenes practices and policies to give you an overall view. 

Take a look at our table below to see our score breakdown for British Gas:

Total score56%
Customer survey score56%
Which? assessment score56%

Here's how British Gas's customer and policy assessments break down:

Customer survey score56%
Customer service overall ***
Accessibility (being able to engage with your firm how you want or need to)
Quality of communications about energy costs
Accuracy of payments
Clarity of statements
Value for money
Which? assessment score56%

Based on a survey of 2,255 British Gas customers carried out in October 2023, and a Which? energy company request for information and desk research in October 2023.

To find out how British Gas compares with other energy companies, see our full results of the best and worst energy companies.

British Gas customer review

British Gas is ranked 10th out of the 16 energy companies rated by 9,025 members of the public in the annual Which? customer survey.

Its customer score of 56% means that British Gas is slightly below average. Most of the biggest suppliers scored similarly with the exception of Octopus Energy, which had much higher customer score of 74%.

British Gas' star ratings were poor to middling. 

Comments from customers were mixed. One said: 'I have found it impossible to get help with things – emailing and social media yielded no responses.' While another was much happier, saying: 'They do everything a utility company should do and I'm happy to be a customer'.

Which? verdict on British Gas

  • Pros Good support for customers who need it, survey results suggest customer service is reasonable
  • Cons Generally poor ratings in our customer survey, among the worst for meeting its smart meter targets

Our British Gas supplier assessment

In October 2023, we looked at four aspects of suppliers' business practices and procedures:

  • Customer service, including how and when you can get in touch, and the quality of self-service help online
  • How well it deals with complaints: how many complaints suppliers get and how quickly they resolve them
  • Supporting customers who need it, including web accessibility, those in vulnerable situations, in financial difficulty, who use prepayment meters and those who need materials in languages other than English 
  • Smart meter targets performance in 2022 (the most recent).

We did this using a combination of the responses to a survey we sent to suppliers and our own assessments.

British Gas received one of the higher scores across suppliers for supporting customers who need it and one of the lowest scores for its performance against smart meter targets. It recently paid into energy regulator Ofgem's redress fund after missing its 2022 installation targets.

British Gas customer service

The best star rating it got was for customer service. However, its three stars aren't so impressive given that five firms scored four stars and one managed the full five.

But it wasn't alone with its three-star customer service rating. Big firms Eon Next and Ovo Energy scored the same, while EDF Energy and Scottish Power managed just two stars. 

In our supplier assessment of its customer service, the British Gas score was among the lowest. But it told us that, from January 2024, it plans to expand its customer service phone line opening hours to 8am to 6pm and open them from 9am to 2pm on Saturdays.

British Gas branded van

British Gas Energy Trust 

The British Gas Energy Trust is an independent charity that helps customers who are struggling to pay their bills – and you don't need to be a British Gas customer to get help. 

You can get advice via local services that it funds and it can give grants to some customers in financial hardship to help them clear their energy debt. 

British Gas common complaints 

When we asked British Gas customers, 7% said they had engaged with the company to make a complaint in the past year.

The most common complaint customers made to British Gas was about their smart meter breaking or not working – 22% of customers who complained did so about this – followed by 19% saying that their bill or statement was unclear.

British Gas got half marks in our assessment of its complaints handling. It received more complaints in the first half of 2023 (the most recent data available) than most other suppliers and wasn't the fastest to resolve them.

Does British Gas support prepayment meters?

Yes. Here's what you need to know:

  • You can top up at a Post Office or Payzone outlet. If you have a smart meter, you can also top up on the British Gas website, app or automated payment phone line.
  • You can get £10 emergency credit if you run out of credit but can't afford to top up.
  • Friendly credit is available overnight between 6pm and 9am Monday to Friday and from 6pm Saturday until 9am Monday, plus bank holidays. It's activated automatically on smart meters and newer non-smart electric meters if you run out of credit, but you can also activate it yourself. If your meter can't do this (no traditional gas meters can), British Gas has a 24-hour service for customers off supply.

Find out whether a prepayment meter is right for you.

Does British Gas sell renewable energy?

British Gas generates renewable electricity as well as buying some of the renewable electricity it sells directly from generators. 

Proportion of renewable electricity sold to customersGenerates renewable electricity?Buys renewable electricity directly from generators (with subsidies)?Buys renewable electricity directly from generators without subsidies?Generates or buys power directly from fossil fuels?Sells green gas?
54%YesYes (2%)YesNoYes (0.05%)

Proportion of renewable electricity according to British Gas's 2022-2023 fuel mix. Other responses based on information provided by suppliers in August 2023.

In August 2023, we asked energy companies for information on a range of sustainability criteria. We awarded them points based on their responses as well as information published on their websites, including the annual Fuel Mix Disclosure (FMD). Aspects we scored included how much of the electricity they supply is renewable and whether they generate renewable energy or buy it directly from generators.

British Gas’ electricity fuel mix in 2022-23 was 54% renewable and 26% nuclear.

British Gas buys around 2% of the renewable electricity its domestic customers use directly from generators and a further 13% is matched by REGO certificates. And 29% is matched with renewable power generated outside the UK, in Europe, using Guarantees of Origin (GoOs). It was the only company that told us it used GoOs, which won't be recognised by government for the next reporting year.

Customers who get a British Gas Green Future tariff have their electricity use matched with renewable sources of generation in the UK and 10% of their gas use matched with green gas.

When we compared energy companies on their green credentials in November 2023, British Gas scored 70%. This places it in the top third of our table of 17 companies rated. But it's not a Which? Eco Provider because it told us its parent company, Centrica, has direct relationships with fossil fuel generators.

Find out more about the differences between energy companies’ renewable electricity and how British Gas compares with others.