So Energy

So Energy is a relatively small energy firm. Its fixed tariffs are 100% renewable and it says 'customer service is at the heart of everything we do'.

Set up in 2015, it now has more than 300,000 customers after merging with ESB Energy in 2021.

So Energy sells only 100% renewable electricity and gives customers a say in where it sources the electricity from – you can use an online poll on So Energy's website to vote for wind, solar, hydro or biomass.

See if you could spend less by using our free tool to compare energy prices.

So Energy score 

We combine the results of our customer survey with an in-depth assessment of companies' behind-the-scenes practices and policies to give you an overall view. 

Take a look at our table below to see our score breakdown for So Energy:

Here's how So Energy's customer and policy assessments break down:

Find out how So Energy compares with other energy suppliers – click to see our full results of the best and worst energy companies.

So Energy customer review

So Energy came in ninth place out of 16 energy companies in our poll of 9,025 members of the public, having slipped down somewhat from fifth position the previous year.

It received average three-star ratings for most aspects of service with the exception of accessibility and value for money, where it received two stars for each.  

Customer feedback in our survey was somewhat mixed. One said: 'Service is great but onetime I had a problem it was a real struggle to get things resolved.' Another added: '''Every time I have contacted them, the issue has been solved within a matter of minutes and excellent communication'.

Which? verdict on So Energy

• Pros: Customers rate it fair for most aspects of service; good at supporting vulnerable customers in our assessment
• Cons: Very poor complaints performance

Our So Energy supplier assessment

In October 2023 we looked at four aspects of suppliers' business practices and procedures: 

• customer service - including how and when you can get in touch, and the quality of self-service help online
• how well they deal with complaints - how many complaints suppliers get and how quickly they resolve them
• supporting customers who need it - including web accessibility, those in vulnerable situations, in financial difficulty, who use prepayment meters, and those who need materials in languages besides English 
• smart meter targets performance in 2022 (the most recent).

We did this using a combination of the responses to a survey we sent to suppliers and our own assessments.

So Energy came bottom of the table in our supplier assessment with a score of 54%. The best supplier, Utility Warehouse, scored 26 percentage points above this with 80%. 

While it did okay at supporting vulnerable customers, scoring eight points out of 10, it came in last place for complaints performance, where it received just four out of 10 points, and it was joint-last for customer service.

So Energy customer service

Its customers gave So Energy an average three stars for customer service in our survey – the best supplier, Octopus, was rated five stars.  

So Energy did much worse in our supplier assessment of its customer service than in our survey, with 7 points out of 15, making it one of the lowest-scoring suppliers in this section.

So Energy common complaints

In our survey, 8% of So Energy customers said they had made a formal complaint during the last 12 months. This is higher than Octopus Energy's 2%, but lower than Boost's 18%.

As well as scoring lowest overall in the Which? assessment, So Energy received the fewest points for handling complaints.

Can I join So Energy with a prepayment meter?

No, So Energy does not accept customers with prepayment meters at the moment. 

Find out whether prepayment energy is right for you.

Does So Energy sell renewable electricity?

So Energy buys some renewable electricity directly from generators. It doesn’t generate renewable electricity itself.

In August 2023, we asked energy companies for information on a range of sustainability criteria. We awarded them points based on their responses as well as information published on their websites, including the annual Fuel Mix Disclosure (FMD). Aspects we scored included how much of the electricity they supply is renewable and whether they generate renewable energy or buy it directly from generators.

In 2022/23 100% of So Energy's fuel mix was renewable.

10% of So Energy customers' electricity use is bought directly from renewable generators that do not receive government subsidies. It does not sell green gas. 

When we compared energy companies on their green credentials in November 2023, So Energy scored 45%. This places it in the bottom half of our table of the 17 companies rated.

Find out more about the differences between energy companies’ renewable electricity and how So Energy compares to others.