Best and Worst UK Energy Suppliers (2024)

While many people prioritise cost when it comes to choosing an energy supplier, customer service is another key factor when deciding which is the best energy provider for you. In order to identify the best and worst energy providers, we've gathered data from Citizens Advice's most recent customer survey of 16 suppliers—because when people are unhappy with the service they've received, they often complain to Citizens Advice about their experience.

The UK's 9 Best Energy Suppliers

According to data from the three months from October to December 2023, Shell Energy, Outfox the Market, E.ON Energy and ScottishPower were the top 4 energy providers in terms of customer satisfaction. Overall, scores have dropped in the current energy-challenged environment, but have improved in the past quarter; top-rated Shell scored an overall 4.0 stars out of 5. They really stood out for customer commitments, rating 5 out of 5 stars in this category. (See what 'customer commitment' means in the methodology section at the bottom of the article.) In terms of contact waiting time, they achieved 4 out of 5 stars, and in terms of number of complaints, they achieved 3 out of 5 stars.

Outfox the Market, ranked 2nd with an overall score of 3.7 (up from 3.3), also stood out for customer commitment (ranking a perfect 5 stars in this category, like Shell), but did a touch worse when it came to the contact waiting time.

E.ON Energy tied for the #2 spot with a score of 3.7 and Scottish Power came fourth with 3.3 points.

For reference, the average customer rating score was 2.9 stars out of 5 (down from 3.3 stars in 2019 but up from 2.6 stars last quarter). So overall scores have dropped in recent years, but they are now improving. Of the top 5 largest energy suppliers in the UK, E.on, Scottish Power and EDF are the only ones in the top 5 for customer service.

Top 8 Best Energy Suppliers

Rank (1 = best)SupplierFewer complaintsCustomer service contact timesCustomer commitmentsOverall rating
1Shell Energy3454.0
2Outfox The Market3353.7
3E.ON Energy2453.7
5EDF Energy1353.0
6Ovo Energy1353.0
7Co-Operative Energy2253.0
8Octopus Energy2253.0
9Utility Warehouse2433.0

Note, a high ranking doesn't mean that a supplier has the cheapest rates, or that it will even be around. Previously, Affect Energy ranked in the top 5 according to the Citizens Advice data—they subsequently ceased to supply gas to all customers and had their Gas Supply Licence revoked...

The last time we updated this data, Octopus reigned supreme with the top spot bu they've since dropped into the bottom half of suppliers...

The UK's 7 Worst Energy Suppliers

At the other end of the spectrum, the five worst energy suppliers in the study were Utilita (ranked the worst), So Energy and Boost Power. None of these scored higher than 2.3 out of 5 stars for overall customer satisfaction. In total, there were 16 energy companies in the study so the 'worst' is ranked number 16. However, there has been some marginal improvement in this lot, e.g. Utilita previously scored just 1.5 out of 5 stars, and they've improved to 2.0 now.

Worst 8 Energy Suppliers

Rank (16 = worst)SupplierFewer complaintsCustomer service contact timesCustomer commitmentsOverall rating
11E (Gas and Electricity)1432.7
12Good Energy2332.7
13British Gas1252.7
14Boost Power1332.3
15So Energy1152.3

Ofgem, the energy regulator, has stepped in on occasion in an effort to improve customer service at the worst offenders. For instance, six years ago, Iresa was banned from taking on new customers until they implemented measures such as responding to customer emails within five working days, recording all customer complaints and identifying vulnerable (e.g., those in debt) customers. Ofgem was not satisfied with the level of improvement in customer service and threatened to revoke Iresa's licence.

Note: There was not enough data on a number of energy suppliers, in particular the smaller companies; without a full data set across all categories these suppliers were excluded from the study. These suppliers might have landed on the best or worst lists, displacing another energy supplier, but we can't know without the data. Citizens Advice only displayed data for suppliers with over 25,000 customer accounts.

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We compare energy suppliers' customer service data from Citizens advice that looks at data from a number of reliable sources; suppliers with more than 25,000 customer accounts are included.

Complaints received

The complaints rating is based on data from:

  • Citizens Advice Consumer Service
  • Extra Help Unit
  • Energy Ombudsman
  • Advice Direct Scotland

Customer service wait times

The customer service rating regarding contact wait times is based on supplier-supplied data related to:

  • average call centre wait time (excluding time spent in sales lines)
  • proportion of emails answered within 2 working days
  • average response time for social media messages (applies if the company is contacted more than 5% of the time through social media)

Customer commitment

Suppliers can score 3 points for being part of the Energy Switch Guarantee and another 3 points for the Vulnerability Commitment (with a max score of 5, not 6, if they do both). Trial members of the Energy Switch Guarantee score 2 points, not 3.

The 'Energy Switch Guarantee' means suppliers have to meet certain criteria such as completing 98% of switches within 5 working days, the whole transfer between tariffs or suppliers will be handled by the supplier of the tariff you are moving to, you have 14 days to change your mind, and more. Find out more about the Energy Switch scheme on the Energy UK website.

The 'Vulnerability Commitment' means suppliers have to promise to improve their support to vulnerable customers (i.e. those who might be facing financial difficulties or illnesses). Find out more about the Vulnerability Commitment on the Energy UK website.


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