Best and worst energy suppliers 2023

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Who are the best energy suppliers?

Each year, Which? releases the results of their annual survey, highlighting both the best and worst energy suppliers in the UK, as rated by customers. Let's take a look at the five highest rated energy suppliers in 2021:

Outfox the Market

Founded in 2017, Outfox the Market is a relative newcomer to the energy supply market in the UK, but it’s quickly gained popularity and this year it topped Which?’s customer satisfaction table for the very first time.

With an overall customer satisfaction score of 82%, it was the only supplier in this year’s survey to score 5 stars for two different categories – bill accuracy and value for money. In fact, Outfox the Market was the only supplier to be rated 5 out of 5 for value for money, and this is evident in the fact that they offer some of the cheapest tariffs in the country.

What’s more, Outfox the Market gets its energy from 100% renewable sources, making it a so-called ‘green’ energy supplier. It also received four stars for bill clarity and customer service.

Octopus Energy

Octopus Energy is another smaller energy supplier, but having topped Which?’s customer satisfaction tables for the last two years running, it’s fast becoming a household name in the UK. It may have been knocked off its perch this year by Outfox the Market, but Octopus Energy continues to perform extremely well and was rated the second-best energy supplier overall in 2021.

It received an overall customer satisfaction score of 80%, being rated 5 stars for bill accuracy and 4 stars for each other category. Octopus Energy is also relatively new to the UK market, being founded in 2016, but it has quickly gained in popularity to now boast over 1.5 million domestic customers, supplying 100% renewable energy.

Avro Energy

Avro Energy got the same star ratings for each category in 2021 as Octopus Energy, but received a slightly lower overall customer satisfaction score of 76%. That being said, it still came out as the third-best rated energy supplier in the UK.

Another small, independent energy supplier, Avro Energy was established back in 2015. It has slowly but steadily attracted a growing customer base, and today it supplies gas and electricity to over 100,000 homes across the country.

People’s Energy

Receiving an average customer satisfaction score of 75%, the fourth best energy supplier in the UK according to Which? is People’s Energy. This is another small energy supplier specialising in providing 100% renewable gas and electricity. What makes this supplier stand out from the rest, however, is that it claims to be not-for-profit, promising to give the majority of the money it makes back to its customers through cheaper bills.

Just like other highly-rated suppliers, People’s Energy scored 5 stars for its bill accuracy. It was also rated four stars each for its bill clarity and value for money.

Pure Planet

Another highly-rated independent energy supplier, Pure Planet has been named in the top 5 suppliers by Which? in both years that it’s been included in the survey. Although performing slightly worse than last year, it still gained a respectable overall customer satisfaction score of 74%.

It received 5 stars out of 5 for its bill accuracy, and four stars each for bill clarity and value for money. Pure Planet is also considered a 100% renewable energy supplier. However, somewhat surprisingly for a company with high customer service ratings, it is a digital-only firm which means all complaints and customer queries are handled exclusively online.

Here is a list of the 10 best energy suppliers in the UK for 2021, according to the Which? survey:

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Who are the worst energy suppliers?

The most notable firms with bad customer scores were E.ON, SSE, British Gas, EDF Energy, Npower, and Scottish Power, otherwise known as the Big Six energy suppliers. None of them featured in the top 10 energy suppliers. In fact, these 6 companies were all in the bottom 7.

Npower was once again the lowest ranked of the six big firms, with an overall satisfaction score of just 54%. British Gas scored best out of the Big Six with customer satisfaction score of 62%, closely followed by EDF Energy with a score of 61%. None of the Big Six rated five stars in any category, where smaller companies excelled in bill accuracy and customer service.

Here is a list of the 10 worst energy suppliers in the UK for 2021, according to the Which? survey:

How are they ranked?

Which? runs an annual survey of around 8,000 energy users to find out which energy suppliers are providing the best service. Customer scores are calculated from how satisfied customers are and how likely they are to recommend their energy supplier. Consumers are also asked to rate the following:

• Bill accuracy
• Clarity of bills
• Customer Service (both on the phone and online)
• How they handle complaints
• Digital tools
• Value for money

These help to calculate the star ratings of each supplier. Each supplier is given a percentage rating which is what their final position is based on.

What to do if you’re unhappy with your energy supplier

Before you lodge any complaints with your energy supplier, be sure to have contacted them first. A lot of the time, problems can be sorted out with one phone call. If problems persist then send a letter or an email to your supplier, with all of your details and account number, outlining the problems. For added impetus include any photos, bills or paperwork that may be relevant. If you still don’t receive any help from your energy supplier, then you can contact the Citizens Advice Consumer Service and they will advise you on how to proceed.

For full details on the process, read our guide on how to complain about your energy supplier. 

You will usually always save money by switching energy suppliers; however, this will depend on whether there are exit fees. To work out whether it is worth switching, find the best energy deal for you by comparing energy providers and subtract the exit fee from the savings you would make by switching. If it works in your favour, make the switch.

Many homes will never have switched energy suppliers, as it can be complicated and takes time. If you have never switched your gas or electricity supplier, or not switched in the last couple of years, you'll almost certainly save money by moving to a different deal. The switching process is straightforward and could save you a lot of money in the long run.