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.

Best and worst energy companies

Which? energy survey results

By Sarah Ingrams

Article 1 of 3

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

Which? energy survey results

Frustrated with your energy firm? Find out what thousands of energy customers think of their suppliers. Use our research to choose the best energy company for you.

Electricity and gas are essential services, but that doesn’t mean you should put up with poor service or high prices.

Our annual UK energy satisfaction survey covers 30 suppliers in Great Britain six in Northern Ireland, and captures the experiences of 8,000 energy customers who tell us what they really think of the service they receive. This gives you a unique guide to finding the very best energy companies you can rely on and avoiding those you can't.

As well as rating the 'Big Six' energy suppliers - British Gas, EDF Energy, Eon, Npower, SSE and Scottish Power - we also investigate smaller companies. This includes Bulb Energy, Co-operative Energy, First Utility, Octopus Energy, Ovo Energy and Utility Warehouse.

Just one energy company earned our prestigious Which? Recommended Provider Award: Octopus Energy.

If you live in Northern Ireland, find out which are the best and worst Northern Ireland electricity and gas firms, according to their customers.

Just want to save money on your energy bills? It's quick and easy to switch energy supplier with Which? Switch, our impartial free switching site. Compare gas and electricity prices now.

Best and worst energy companies

See the results of our survey in the table. Click on each company to find out more about it. Use the link at the end of the table to see the full results, including whether companies passed our pricing assessment.

Energy companies rated
  Company Bill accuracy Customer service (phone) Customer service (online) Complaints handling Helping you understand and reduce energy use Value for money Customer score

Octopus Energy


Robin Hood Energy

- 78%

So Energy

- 78%


- - 76%

Tonik Energy

- 76%

Ovo Energy


Utility Warehouse


Bristol Energy

- 72%

Bulb Energy






Boost Energy



- - - - 70%

Flow Energy

- 68%

Green Network Energy

- 68%

Co-operative Energy


Shell Energy (formerly First Utility)


Green Star Energy


Avro Energy

- 64%

Sainsbury's Energy* (when part of British Gas)


Together Energy

- 60%



EDF Energy




iSupply Energy

- - - 57%

British Gas




Scottish Power


Spark Energy




Click here for the full survey results table

Table notes
The customer score combines customers’ overall satisfaction with their likelihood to recommend, and is not directly linked to the star ratings.
Overall average customer score: 61%. This is weighted for the market share of each energy company.
(-) indicates too few responses to give a rating.
In bold – customer scores over 70%, above average procedures and practices score and combined 2018 call waiting and complaint score.
In red – Which? Recommended Provider
Sample sizes: Octopus Energy (168),  Robin Hood Energy (68), So Energy (98), Ebico (45), Tonik Energy (74), Ovo Energy (433), Utility Warehouse (154), Bristol Energy (57), Bulb Energy (168), Ecotricity (75), Utilita (110), Boost Energy (65), Engie (40), Flow Energy (66), Green Network Energy (89), Co-operative Energy (135), First Utility (132), Green Star Energy (72), Avro Energy (69), Sainsbury's Energy (135), Together Energy (68), SSE (929), EDF Energy (404), Eon (5122), iSupply Energy (45), British Gas (1,002), Npower (728), Scottish Power (882), Spark Energy (79), Solarplicity (84). Economy Energy and Extra Energy have stopped trading since our survey so their results aren't included above. Economy Energy was in 29th position with a customer score or 53%. Extra Energy was in =26 position with a 56% customer score. *Sainsbury's Energy was a partnership with British Gas until April 2019 and these results date from that period.

 Survey: September 2018.

Looking for our Northern Ireland results? Go to Northern Ireland electricity and gas firms.

Interpreting the Which? energy survey results

When you reveal the full table above, you'll see how the companies scored in our other assessments, including how fast they respond to customers online or on the phone, how they compare for resolving complaints and the results of our procedures and practices assessment. This compares companies' practices for:
  • Billing
  • Complaints
  • Customer service
  • Product management

Who's top of the Which? energy survey?

Octopus Energy tops the table this year, followed closely by Robin Hood Energy, So Energy, Ebico and Tonik Energy.

Octopus Energy is also this year’s only Which? Recommended Provider (WRP) for energy.

Robin Hood Energy missed out on WRP status because it scored below average on our performance assessment, which takes into account customer waiting times and complaints. So Energy missed out as it scored below average in our procedures and practices assessment. Ebico and Tonik Energy scored below average on both of these assessments. Find out more about them on our Which? Recommended Provider page.

Price is the most important consideration for you when choosing a new energy supplier, according to our survey, so it’s no surprise that the highest-scoring energy companies are considered good value for money by their customers.

Price isn’t everything though – and being rated good value for money by customers doesn’t mean an energy supplier is the cheapest on the market. Renewable energy firm Ecotricity (in joint eighth position) has one of the priciest tariffs on the market. But its customers rate it good value for money, showing that it keeps them satisfied.

The Big Six

The biggest six energy suppliers are in the lower half of the table. Npower and Scottish Power are joint-lowest scoring among them, though not the lowest-scoring suppliers overall. This is the first time that Npower has not been the lowest-ranked company in our survey.

SSE is the highest-rated of the Big Six this year, in 22nd position. Its customer score is just four percentage points different to Npower and Scottish Power’s however, showing that customers find that there’s little to choose between them.

See our Big Six energy companies guide for full details about each firm.

Who's bottom of the Which? energy survey?

Small firm Solarplicity is the worst energy supplier in our 2019 survey, according to its customers.

Spark Energy and joint-placed Npower and Scottish Power complete the bottom three positions. Spark Energy was also in the bottom three last year. Since then it has gone bust and been bought by Ovo Energy. So we’ll be keeping an eye out to see if customers’ opinions improve.

Our survey shows the importance of customer service. Nearly half (49%) of lowest-ranked energy firm Solarplicity’s customers rated its customer service poor or very poor. Plus a third (34%) said they’d had a problem with its customer service in the last two years.

Most popular way to contact your energy supplier

Although you can contact most energy companies by email, live chat and social media, the majority of us still choose to pick up the phone to speak with our energy company.

We conducted snapshot undercover investigations to reveal how long customers have to wait for their phone calls to be answered by a human being. We also contacted energy suppliers via live chat (if they offered it) or email or online form (if they didn’t offer live chat) to find out how long it takes to get a response that isn’t an automated acknowledgement.

In our latest investigation in September and October 2019, we contacted energy suppliers a total of 852 times. We made 432 phone calls to 36 energy companies, sent 420 emails, online form requests and live chat messages.

Which energy companies are quickest?

Answering the phone quickly is not impossible. So Energy managed to answer calls to its customers in just 38 seconds on average, making it the fastest energy supplier to put us through to a human. 

Overall there were five firms that put us through to a human in under a minute on average this year, and another four kept us waiting less than two minutes on average.

In contrast Scottish Power kept callers in our snapshot investigation waiting on the phone for 21 minutes, 24 seconds on average.

So Energy vs Scottish Power: customer service telephone waiting times

Read our story on energy company customer waiting times 2019, which includes how promptly companies responded to live chat and whether it’s worth emailing if you need a speedy response.

We can help you save money on your energy bills. Use our independent free switching site, Which? Switch, to find the cheapest energy deal.