Most complained about vitality suppliers REVEALED: See the place yours ranks

Two challenger energy companies have been deemed to have the worst customer service in the industry, according to a Citizens Advice. 

It totted up the number of complaints to Citizens Advice, Advice Direct Scotland and the Energy Ombudsman about each firm, as well as looking at waiting times and customer commitments scores. 

The data took into account all energy firms with at least 25,000 customers.  

Challenger energy brands Rebel Energy and So Energy have the worst customer service, according to the results.  

Rebel Energy came bottom of the list with a score of 2.4 out of 5 with 53 complaints per 10,000 customers between October and December 2024.

Its customers waited 1 minute and 42 seconds on average when they called its helpline, while just 62.9 per cent of emails were responded to within two days.

So Energy scored 2.5 out of 5 with 74.5 complaints per 10,000 customers. Its call waiting time was higher at 2 minutes and 1 second, while 73.5 per cent of emails were answered within 48 hours. 

Energy complaints: Citizens Advice Bureau ranks suppliers’ customer complaints

However, So Energy scored higher than Rebel because it offers a switch guarantee and a vulnerability commitment.

If a supplier is a member of the Energy Switch Guarantee, they have to meet certain criteria, including completing 98 per cent of switches within five working days.

A supplier with a vulnerability commitment promises to improve support to those facing financial difficulties or illnesses.

While it placed in the middle of the rankings overall, British Gas had the second-highest number of customer complaints at 81.3 per 10,000 customers. 

Utility Warehouse topped the list with a score of 3.8 out of 5, scoring highly on its contact waiting time.

Customers calling their helpline waited just 1 minute and 14 seconds, while 99.3 per cent of emails were replied to within 2 days. 

It received 25.3 complaints per 10,000 customers.

Utility Warehouse differs from other energy suppliers in that it also offers customers broadband, mobile and insurance, and allows customers to bundle different services in a single bill.

Rob Harris, chief operating officer of Utility Warehouse, said: ‘We’re proud to be in our customers’ corner, and finishing top of the Citizens Advice energy supplier rankings for the second quarter in a row proves that commitment.

‘It’s testament to our belief in the power of people helping people. Whether that’s partners helping their local communities or our customer service teams helping our customers, we put people first – and it shows.’

Behind Utility Warehouse came fellow challenger Outfox the Market, which launched in 2017, with a score of 3.6 out of 5.

It received fewer complaints than Utility Warehouse with 20.6 per 10,000 customers, but customers were left waiting on the phone for an average of 2 minutes and 6 seconds. 

It responded to 100 per cent of all customer emails within 2 days.

Scottish Power was the highest ranking Big Six energy supplier with a score of 3.6 out of 5 and 46.7 complaints per 10,000 customers in the fourth quarter of 2024.

Customers waited on the phone for 1 minute and 25 seconds on average while 96.1 per cent of emails were responded to within 2 days.

Andrew Ward, chief executive of Scottish Power’s customer business, said: ‘Our teams work tirelessly to improve and enhance our services for all our customers and I’m delighted to see their efforts reflected in this latest Citizen’s Advice research.

‘Looking after our customers is at the heart of everything we do and we’re committed to providing them with the best service possible; not only reducing call waiting times but giving our customers a number of ways to contact us that best suits their individual needs.’ 

Overall, Utilita received the most complaints per 10,000 customers followed by British Gas with 81.3. Good Energy had the fewest number of complaints with 9.7 per 10,000.