EDF Energy So Energy (August 2026)
Overview
EDF Energy wins for its strong customer service scores and established app, though So Energy offers a cheaper variable tariff and faster call answer times.
EDF Energy has the higher Trustpilot score and a substantially larger review base. However, So Energy has higher app ratings, a lower variable tariff cost and faster call answering times.
About EDF Energy and So Energy
Who is EDF Energy?
EDF Energy is the UK retail arm of the French state-owned energy group Électricité de France. It was formed in the early 2000s after buying several regional electricity boards and later took over British Energy. Today, it is one of the UK's largest domestic energy suppliers and a major generator of electricity.
Who are So Energy?
So Energy was set up in 2015 as a challenger energy supplier. In 2021, ESB Energy, part of the Irish state-owned ESB Group, bought a majority stake in the business, and the two companies merged. Today, it is a mid-sized supplier that focuses on customer service and renewable energy.
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Tariffs and pricing
So Energy currently provides the cheaper overall option in this comparison. Its So Green Tracker 24m is a variable tariff priced at £1,687 a year, which requires a 24-month contract term and carries a £190 exit fee.
By comparison, EDF Energy's lowest-priced option is the Simply Tracker Sep27. This variable tariff costs £1,755 a year and has no fixed term, though leaving it incurs a £50 exit fee.
For households preferring to lock in their rates, both suppliers offer fixed deals that cost roughly the same under our typical use assumptions. EDF Energy's Simply Fixed 2Yr Aug28 is priced at £1,824 a year for a 24-month term with a £150 exit fee. Alternatively, So Energy's So Heron 18m costs £1,829 a year over an 18-month term, with a £190 exit fee.
Tariff options
EDF Energy tariffs
EDF Energy offers a range of mainstream tariffs, including standard variable and fixed-term deals with terms from 12 to 24 months. It also gives customers specialist options, such as tracker tariffs, electric vehicle tariffs, and export tariffs for homes with solar panels.
So Energy tariffs
So Energy focuses on a streamlined range of standard variable, tracker, and fixed-term tariffs with terms from 12 to 24 months. It also provides a specialist tariff for electric vehicle drivers and an export tariff for households that generate their own electricity.
Customer reviews
EDF Energy holds a higher Trustpilot rating, scoring 4.8 out of 5 from a substantial 243,334 reviews. Within this sample, 83% of reviewers award the supplier five stars, frequently citing polite staff and efficient query resolution.
So Energy achieves a 4.5 out of 5 Trustpilot score based on 30,220 reviews, with 73% of these at five stars. While many users note helpful staff and fair pricing, some report communication delays and unexpected billing charges.
In the annual Which? customer satisfaction survey, the two suppliers achieve comparable results. So Energy receives a score of 60 out of 100, while EDF Energy sits slightly lower at 58 out of 100.
App experience
EDF Energy maintains a highly adopted app, recording over 1,000,000 installs on Google Play. It scores 4.6 out of 5 from 185,000 ratings on iOS, and 4.4 from 50,315 ratings on Android. The supplier recently updated the interface to include quick actions on the home screen for routine account management.
So Energy's app scores slightly higher across both platforms, though these figures rely on a much smaller user base. It holds a 4.7 score on iOS from 197 ratings, and 4.6 on Google Play from 127 ratings. Recent updates have primarily focused on general bug fixes rather than new features.
Customer service and support
In the latest Citizens Advice rankings, the two suppliers perform similarly. EDF Energy scores 2.9 out of 5 to place 11th, while So Energy follows closely with 2.86 out of 5 in 12th position.
So Energy demonstrates faster direct contact times. It answers phone calls in an average of 1 minute 6 seconds, compared to 2 minutes 46 seconds for EDF Energy. Additionally, So Energy replies to 91.3% of emails within two days, edging past EDF Energy's 85.6%.
For social media inquiries, So Energy averages a response time of 5 minutes 51 seconds. EDF Energy does not currently publish its social media response data. Both suppliers maintain formal vulnerability commitments registered with Citizens Advice.
EDF Energy's general support lines operate Monday to Thursday from 8am to 6pm, and Fridays from 8am to 4pm. So Energy is available on weekdays between 9am and 5pm. Neither supplier opens its call centres on weekends.
Complaints and performance
In Q1 2025, EDF Energy received 1,528 complaints per 100,000 customers. It fixed 77% of these by the end of the next working day, and 94% within eight weeks. The most common reason for complaints was customer service at 36%, which covers general service issues. This was followed by payment issues (15%) and billing and meter reading issues unrelated to meter type (15%).
Green energy comparison
EDF Energy
EDF Energy's electricity fuel mix is largely nuclear, with some fossil fuels and renewables. The supplier is heavily involved in building new nuclear power stations in the UK to help the country reach its net zero targets. It backs its relevant tariffs with zero-carbon nuclear electricity rather than relying solely on renewable energy certificates. It does not currently offer a dedicated green tariff or carbon offsetting for its domestic customers.[1]
So Energy
So Energy's electricity fuel mix is a mostly renewable mix, with some fossil fuels. The supplier guarantees that all its fixed tariffs are powered by 100% renewable electricity, backed by Renewable Energy Guarantees of Origin (REGO) certificates. It also lets customers vote each year on which UK-based renewable energy generation it invests in. As well as supplying energy, the company helps customers reduce their carbon footprint by installing green technology like solar panels and home batteries.[2][3]
Our verdict
| If you care most about | Choose |
|---|---|
| The lowest annual cost on our assumptions | So Energy |
| Overall customer service | EDF Energy |
| A well-rated mobile app | So Energy |
| A greener fuel mix | So Energy |
This is a close comparison: EDF Energy has stronger Trustpilot evidence, while So Energy is cheaper on our tariff assumptions and leads on app ratings and fuel mix.
EDF Energy is one of the UK's largest suppliers, supported by an established app and high Trustpilot ratings. It may suit households looking for a provider with a long track record of positive reviews across hundreds of thousands of customers.
Alternatively, So Energy may be a suitable option if your priority is lower pricing and faster contact times. It currently provides a cheaper variable tariff and answers calls more than a minute faster on average, provided you are comfortable with the high exit fee on its lowest-priced deal.
- High Trustpilot score based on a large volume of reviews
- Lower exit fee on its cheapest variable tariff
- Widely used app with regular updates
- Higher cost for its cheapest variable tariff
- Longer average call wait times
- Cheaper overall variable tariff
- Faster average phone and email response times
- Includes 100% renewable electricity on green tariffs
- Lower overall Trustpilot score
- High £190 exit fee attached to its cheapest variable tariff
- App store ratings rely on very small sample sizes
Frequently asked questions
Who is better, EDF Energy or So Energy?
This is a close comparison: EDF Energy has the higher Trustpilot score, while So Energy has the cheaper variable tariff, faster phone response times and higher app ratings.
Which supplier has the cheapest tariff?
So Energy currently offers the cheaper overall deal with its So Green Tracker 24m variable tariff at £1,687 a year. EDF Energy's cheapest option is the Simply Tracker Sep27 variable tariff at £1,755 a year.
Which supplier has better customer reviews?
EDF Energy has a higher Trustpilot score of 4.8 out of 5 from over 243,000 reviews. So Energy scores 4.5 out of 5 from just over 30,000 reviews.
Does EDF Energy or So Energy have a better app?
So Energy has slightly higher app ratings, scoring 4.7 on iOS and 4.6 on Android, but these are based on fewer than 200 ratings. EDF Energy's app scores 4.6 on iOS and 4.4 on Android, but is based on hundreds of thousands of ratings.
Which supplier is easier to contact?
So Energy answers calls faster, taking 1 minute 6 seconds on average compared to EDF Energy's 2 minutes 46 seconds. So Energy also replies to a higher percentage of emails within two days.
Should I switch to EDF Energy or So Energy?
If you want a highly rated app and strong customer service scores, EDF Energy is the better choice. If you prefer a cheaper variable tariff and faster call answer times, So Energy is a strong alternative.
Do EDF Energy and So Energy charge exit fees?
Yes, both suppliers charge exit fees on their cheapest tariffs. So Energy charges £190 on its cheapest variable deal, while EDF Energy charges £50 on its cheapest variable option.
Are EDF Energy and So Energy fixed tariffs similar in price?
Yes, their cheapest fixed deals are effectively identical in price. EDF Energy's cheapest fixed tariff costs £1,824 a year, while So Energy's costs £1,829 a year.
Do both suppliers offer green energy?
So Energy offers a green tariff backed by 100% renewable electricity. EDF Energy does not currently list a dedicated green tariff in the data we compared.
Are EDF Energy and So Energy open on weekends?
No, neither supplier is open on weekends. EDF Energy is open Monday to Friday, closing at 6pm most days and 4pm on Fridays. So Energy is open weekdays from 9am to 5pm.
What changed this month
This month, So Energy's play store days since last update rose from 22 to 46, So Energy's iOS app days since last update rose from 22 to 45, and EDF Energy's iOS app updates in last 90 days rose from 0 to 3. There were 28 other data changes this month — see the full changelog below for details.
Data changes this month (36)
EDF Energy
- Trustpilot reviews234,962 → 243,334
- iOS app ratings count182,000 → 185,000
- iOS app days since last update754 → 6
- iOS app updates in last 90 days0 → 3
- Play Store rating4.4540496 → 4.4256063
- Play Store ratings count49,305 → 50,315
- Play Store days since last update20 → 7
- Play Store positive ratings %87.2 → 86.3
- Play Store negative ratings %9.1 → 9.8
- Play Store neutral ratings %3.7 → 3.9
- Play Store net-positive %78.1 → 76.5
- Cheapest fixed tariff£1,692.77 → £1,824.37
- Cheapest tariff£1,692.77 → £1,754.76
- Cheapest tariff exit fee£150 → £50
- Cheapest tariff term24 months → 0 months
So Energy
- Trustpilot reviews29,771 → 30,220
- Trustpilot negative reviews replied %99 → 100
- iOS app ratings count170 → 197
- iOS app days since last update22 → 45
- iOS app updates in last 90 days3 → 2
- iOS sampled reviews avg stars3.8 → 3.67
- iOS sampled positive reviews3 → 2
- iOS sampled negative reviews2 → 1
- Play Store rating4.6 → 4.62
- Play Store ratings count118 → 127
- Play Store days since last update22 → 46
- Play Store positive ratings %91.3 → 92
- Play Store negative ratings %4.3 → 3.2
- Play Store neutral ratings %4.3 → 4.8
- Play Store net-positive %87 → 88.8
- Cheapest variable tariff£1,744.17 → £1,687.08
- Cheapest fixed tariff£1,637.61 → £1,828.88
- Cheapest tariff£1,637.61 → £1,687.08
- Cheapest fixed tariff term24 months → 18 months
- Tariff count5 → 6
- Variable tariffs available2 → 3
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Written by
Rob Gibbs
Hi, I'm Rob, and I run Energy-Review.co.uk. I initially started this project in 2018 when I was looking to switch energy suppliers and found there wasn't a website that provided simple, data-backed reviews on all the suppliers available. Since then, I have spent a lot of time (too much, some may say!) looking at all publicly available data about each supplier and writing reviews using this information. These reviews are updated as regularly as possible, and any data is backed up by a source where necessary. I have also started writing guides on various energy-related topics, which hopefully you will find useful. If you find any issues, please use our contact form to let us know.