Electricity and gas are essential services and we spend a fair chunk of our income on them. So you shouldn’t have to put up with poor service.
Our annual energy satisfaction survey covers 17 suppliers in Great Britain. Our most recent results were published in January 2026, based on nearly 12,000 energy customers telling us about the service they receive.
We also conducted our own in-depth assessment of firms’ practices to find out which are set up in the best interests of their customers.
The results of both are combined to make our findings as useful as possible and reveal the companies that are doing their best for customers.
This year, four providers impressed us enough to be named Which? Recommended Providers: E (Gas & Electricity), Octopus Energy, 100Green and Sainsbury’s Energy.
The table below covers providers available in England, Scotland and Wales. If you live in Northern Ireland, see our advice on NI electricity and gas firms.
Compare prices and contracts with our free energy tool or find out how to get the best energy deal.
Best energy companies
Below are the results from our customer survey and our unique assessment of company practices. We’ve combined these to give a total score for each supplier.
We surveyed 11,945 members of the general public in September-October 2025. We assessed firms’ behind-the-scenes practices in September-November 2025 to compare their approaches to methods of contact, supporting customers who need it, how they performed against their smart meter targets, switching, and complaints data.
Click the name of each company to read their detailed review pages, or scroll down to see their detailed star ratings compared.
Table notes: Customer results based on a September-October 2025 online survey of 11,945 energy customers among the general public. Customer score: based on satisfaction and likelihood to recommend. Customers rated other service aspects, shown as star ratings. We require 50+ responses to give a rating. Which? assessment score based on a request for information and desk research in September-November 2025. Total score is a combination of customer score and Which? assessment score.
Sample sizes for customer score: E (Gas & Electricity) (92), Octopus Energy (2,708), 100Green (146), Co-op Energy (112). Sainsbury’s Energy (79), Outfox Energy (74), Good Energy (78), Utility Warehouse (291), Utilita (323), Ecotricity (115), Fuse Energy (112), E,ON Next (1663), Ovo Energy (1,011), So Energy (108), British Gas (3,179), EDF Energy (1,123), Scottish Power (780)
Detailed energy provider score breakdown
The table below shows the full results of both our energy customer survey and our in-depth assessment of suppliers’ practices.
Scroll right to see the star ratings from our customer survey, followed by the ratings from our assessment.
Tables notes: Customer results based on a September-October 2025 online survey of 11,945 energy customers among the general public. Customer score: based on satisfaction and likelihood to recommend. Customers rated other service aspects, shown as star ratings. We require 50+ responses to give a rating.
Sample sizes: E (92), Octopus Energy (2,708), 100Green (146), Co-op Energy (112). Sainsbury’s Energy (79), Outfox Energy (74), Good Energy (78), Utility Warehouse (291), Utilita (323), Ecotricity (115), Fuse Energy (112), E,ON Next (1663), Ovo Energy (1,011), So Energy (108), British Gas (3,179), EDF Energy (1,123), Scottish Power (780).
Which? assessment score based on: complaints performance (30%), contacting your supplier (25%), supporting customers who need it (25%), performance against (2023) smart meter targets (10%) and switching (10%).
Total score is a combination of customer score and Which? assessment score. Which? Recommended Providers (WRP) must achieve 70% customer score, receive three stars and above in all survey star ratings and score above average in the Which? Assessment.
If you live in Northern Ireland, see our overview of NI electricity and gas firms.
What makes an energy company the best?
Here’s how we calculate the Which? assessment score:
- 30% Complaints performance
- 25% Contacting your supplier
- 25% Help for those who need it
- 10% Smart meter policies and targets
- 10% Switching
We also used customers’ survey responses on the following to award star ratings:
- Customer service overall
- Ease of contacting
- Usefulness of communications about energy costs
- How accurate your payments are
- How clear your statements are
- Value for money
- Customer communications.
Only customers’ satisfaction with their supplier and how likely they are to recommend it determine the customer score. These additional star ratings give you extra insight into the areas that are important for you.
We continually review and improve our criteria to make sure we’re assessing the measures most important to customers.
To become a Which? Recommended Provider, an energy supplier must achieve a customer score of at least 70% and receive three stars and above in all survey star ratings. It must also score above average in our assessment of supplier practices.
This year’s Which? Recommended Providers for Energy are E (Gas & Electricity), Octopus Energy, 100Green and Sainsbury’s Energy.
Find out more about what it takes to become an energy Which? Recommended Provider.
Top-scoring energy companies
E (Gas & Electricity)
Along with a good customer score, E (Gas & Electricity) earned the highest overall score in our behind-the-scenes assessment. It performed well when it came to helping customers in need, dealing with complaints, and switching.
ranked total score of 17 energy companies reviewed
Octopus Energy
Octopus Energy earned the third highest customer score in our survey, based on real customer satisfaction and likelihood to recommend, and is a Which? Recommended Provider for the ninth year in a row.
ranked total score of 17 energy suppliers reviewed
100Green
100Green has excellent customer service, according to our survey, though it’s not the best choice if you’re on a pre-payment meter. And it only squeaked by with an average score in the Which? assessment.
ranked total score of 17 energy companies reviewed
Sainsbury’s Energy
Sainsbury’s Energy has upped its game since last year, with decent scores from its customers and in the Which? assessment. It scored a maximum 10 out of 10 for helping people who need it.
ranked total score of 17 energy companies reviewed
Lowest-scoring energy companies
British Gas, EDF Energy, and Scottish Power have the lowest overall scores in this year’s assessment. All three received low scores in both the customer survey and the suppliers practices assessment. Each company received a customer score of less than 60%, and only two out of a possible five for each of the star ratings.
The overall average customer score was 72% this year, an improvement over last year, while the average Which? assessment score was 61%.
Read more about British Gas, EDF Energy, and Scottish Power.
Traditional energy companies
For a long time, six energy firms dominated the market. But major changes over the past few years have shaken up the energy market. Four of the original six still supply more than half of energy customers today – British Gas, EDF Energy, E.ON Next and Scottish Power.
But they’ve been joined by relative newcomers Ovo Energy, which took over from SSE Energy Services as a domestic supplier, and Octopus Energy. Meanwhile former giant Npower shifted its customer base to E.ON in 2021.
Octopus Energy is now the largest supplier of electricity and the second-largest (after British Gas) for gas. Its dramatic growth in recent years is partly down to it taking on 1.5 million customers from failed supplier Bulb and 1.3 million from Shell.
Ovo Energy is currently the fourth-largest supplier. It bought SSE Energy Services’ domestic customers in 2020.
E.ON Next is the highest-ranked of the traditional big firms this year, with an overall score of 66%.
Scottish Power has the lowest overall score.
Small energy companies
While a handful of big suppliers – British Gas, EDF Energy, E.ON Next, Octopus Energy, Ovo and Scottish Power – dominate the market, there are smaller energy companies trying to set themselves apart.
Some are too small to be included in our annual investigation so we’ve rounded them up here to give you the full picture.
If you live in Northern Ireland, learn more about the Northern Ireland energy market.
Should you use a small energy company?
An energy company being big and established doesn’t mean it’s the best for you. In fact, some of the largest and oldest companies were in the lower half of the table in this years rankings.
Some smaller firms do very well in our assessments, including Which? Recommended Providers 100Green and E (Gas & Electricity).
The ultimate risk of choosing a smaller supplier is that it could go bust. In the energy crisis of 2021-22, many small companies stopped trading amid volatile wholesale prices.
If stability is the most important thing to you, you may feel more comfortable with a larger company. But remember that it’s still possible for a bigger firm to go out of business or be taken over.
If your supplier does go under or is bought by another firm, your gas and electricity won’t be cut off. There are processes in place, set by energy regulator Ofgem, to protect your credit balance and automatically transfer you to a new supplier.
Home Energy
Home Energy provides gas and electricity to homes and businesses.
It’s a family-owned company with a stated mission to ‘provide affordable energy while delivering the highest-quality customer service’.
It claims to offer the UK’s cheapest variable tariff.
Huddle
Huddle promises to sort out bills for shared households, so you don’t have to.
It combines energy bills with water, broadband and TV into one payment, then charges each housemate for their share.
Each person pays their portion of the bills and Huddle says it will never ask you to cover for your housemates.
London Power
London Power, launched in January 2020, is an energy company exclusively for London residents. Founded by the Mayor of London, London Power is a partnership between City Hall and Octopus Energy.
London Power says prices will always be fair and affordable. At the end of your contract, you will be moved onto the cheapest similar plan.
Any profits go into projects to help London become a zero-carbon city.
National Gas
Previously known as British Natural Gas, this small supplier is not to be confused with Britain’s biggest supplier, British Gas, nor with the transmission network of the same name.
It supplies commercial and residential gas across the UK – it doesn’t sell electricity tariffs. Its services also include supply connections and disconnections, and site works.
Tulo Energy
Tulo Energy launched in 2017, and started taking on customers in 2019. It says it aims to be as straightforward as possible and to have transparent pricing.
Customers can manage their accounts online or via Tulo’s app.
Energy suppliers that have ceased trading
Bulb, which had 1.7 million customers, went into special administration in November 2021. Shell Energy was bought by Octopus Energy in December 2023.
The following small companies have also gone out of business in recent years.
- Ebico Living, a not-for-profit supplier, ceased its operations after its energy supply partner, Rebel Energy, ceased trading on 1 April 2025.
- Engie withdrew from the UK domestic energy market in 2020, and its customers were transferred to Octopus Energy.
- Qwest Energy was a local energy provider committed to supporting the Cheshire West and Chester regions. Along with Engie and Roar Power, its customers transferred to Octopus Energy starting in 2020.
- Rebel Energy announced that it had ceased trading on 1 April 2025. Its customers have been transferred to British Gas.
- Roar Power provided gas and electricity to homes in Norwich and the east of England. Its customers transferred to Octopus Energy (along with Engie and Quest Energy) in 2020.
- Tomato Energy ceased trading on 5 November 2025, after finding its rapid growth unsustainable. Ofgem has appointed British Gas to take on Tomato Energy’s customers.
If your small energy supplier goes out of business, and you’re not happy with the company that Ofgem transfers you to, you’re free to switch to another supplier. You won’t be charged any exit fees. Do not attempt to switch before the automatic transfer process is complete.
Use our free, independent comparison tool to compare tariffs and select the best supplier for you, based on price and customer satisfaction.
Feeling the pinch with energy bills? Read our tips to cut your energy costs.