Octopus Energy So Energy (July 2026)
Overview
Octopus Energy wins on customer service and app ratings, though So Energy currently offers cheaper tariffs.
Octopus Energy scores higher across customer service metrics, app ratings, and independent reviews. Meanwhile, So Energy currently provides cheaper fixed and variable tariffs, though it ranks lower in overall service evaluations.
About Octopus Energy and So Energy
Who are Octopus Energy?
Set up in 2015 and backed by the Octopus Group, Octopus Energy grew by taking on households from closed suppliers and buying Bulb and Shell Energy UK. Today, it is the UK's largest domestic energy supplier. It manages accounts using its own software platform called Kraken.
Who are So Energy?
Set up in 2015, So Energy merged with ESB Energy in 2021 and is now an established UK domestic supplier. It focuses on simple tariffs and renewable energy, letting customers vote each year on the type of UK renewable energy generation they want the company to invest in.
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Tariffs and pricing
So Energy provides the cheaper overall deal with its So Elk 24m fixed tariff, priced at £1,638 a year. In comparison, the cheapest option from Octopus Energy is a 12-month fixed deal costing £1,697 a year. The So Energy tariff secures rates for 24 months, whereas the Octopus Energy contract lasts for 12 months.
Households looking for a flexible tariff will also find So Energy to be the cheaper option. Its So Green Tracker tariff is estimated at £1,744 a year, compared to £1,792 a year for the Flexible Octopus standard variable tariff. Flexible Octopus has no exit fee, while So Green Tracker has a 12-month term and a £100 exit fee.
Leaving a fixed deal early incurs a penalty with either provider. So Energy applies a £190 exit fee on its cheapest fixed tariff, while Octopus Energy charges £100.
Tariff Options
Octopus Energy
Octopus Energy offers standard variable and fixed-term tariffs, as well as a wide range of smart and specialist tariffs for homes with electric vehicles, heat pumps, solar panels, and battery storage.
So Energy
So Energy offers a range of standard variable, tracker, and fixed-term tariffs, alongside a specialist smart tariff for electric vehicle owners.
Customer reviews
Octopus Energy holds a higher Trustpilot score of 4.8 from a large volume of reviews, compared to So Energy's 4.5. The majority of Octopus Energy reviews (90%) are five-star. So Energy receives 73% five-star ratings alongside a 12% share of one-star reviews.
Feedback for Octopus Energy frequently highlights efficient staff and quick response times. While many users note helpful service, a minority report issues regarding phone line quality or unanswered calls.
So Energy reviews often mention professional staff and clear tariff explanations. Conversely, some customers express frustration over the automated call handling system and extended wait times to speak with an agent.
In the annual Which? survey, Octopus Energy achieves a score of 74 out of 100, whereas So Energy scores 60. Octopus Energy also records higher marks in specific Which? categories, including 8 out of 15 for complaints handling and 10 out of 10 for help for those who need it.
App quality and features
Both suppliers provide highly rated applications on the App Store, where Octopus Energy scores 4.8 and So Energy scores 4.7. Octopus Energy maintains a significantly larger user base, recording over 1,000,000 Android installs compared to 10,000+ for So Energy.
On Google Play, So Energy achieves a slightly higher score of 4.6 compared to 4.4 for Octopus Energy. This metric, however, is drawn from a much smaller pool of ratings.
A recent sample of iOS reviews for So Energy averages 3.8 stars; users often praise the simple design but occasionally note issues when submitting meter readings. Both suppliers actively maintain their software and have released updates very recently.
Customer service and support
Octopus Energy places 4th in the Citizens Advice table, achieving an overall score of 3.67 out of 5. So Energy ranks 12th with a score of 2.86 out of 5.
So Energy answers customer service calls slightly faster, recording an average wait time of 1 minute 6 seconds compared to 1 minute 17 seconds for Octopus Energy. Additionally, So Energy responds to a higher proportion of emails within two days (91.3%) than Octopus Energy (86.1%).
Both suppliers maintain formal vulnerability commitments registered with Citizens Advice. Phone lines for Octopus Energy are closed at weekends, and So Energy similarly operates on weekdays only.
Complaints and performance
In Q4 2025, Octopus Energy received 495 complaints per 100,000 customers. It resolved 45% of these by the end of the next working day, and 79% within eight weeks. The main reasons for complaints were payment issues, billing, and smart billing. To help fix these issues, Octopus expanded its Octo Assist Fund with £15m and tightened back billing rules so customers are not charged for energy used more than 12 months ago. So Energy’s complaints figure covers Q2 2025, so the two complaint-rate figures are not a like-for-like head-to-head comparison.
Green Energy Comparison
Octopus Energy
Octopus Energy offers 100% zero-carbon electricity. Based on Citizens Advice data from early 2026, its electricity fuel mix is a mostly renewable mix, with some nuclear. The company invests directly in wind and solar power through its own generation business, Octopus Energy Generation. It also helps customers move away from fossil fuels by installing heat pumps, solar panels, and electric vehicle chargers. Through the Octopus Fan Club, customers living near specific wind turbines get cheaper electricity when the turbines are spinning.
So Energy
So Energy backs its fixed tariffs with renewable electricity certificates (REGOs). Based on Citizens Advice data from early 2026, its electricity fuel mix is a mostly renewable mix, with some fossil fuels and a small amount of nuclear and other sources. The company lets customers vote on the type of UK-based renewable energy generation they want it to invest in.[1]
Our verdict
| If you care most about | Choose |
|---|---|
| The lowest annual cost on our assumptions | So Energy |
| Overall customer service | Octopus Energy |
| A well-rated mobile app | Octopus Energy |
| A greener fuel mix | Octopus Energy |
Octopus Energy wins on customer service and app ratings, though So Energy currently offers cheaper tariffs.
Octopus Energy leads this comparison based on the available data. It achieves higher marks across customer reviews, Citizens Advice rankings, and Which? scores.
So Energy may suit households prioritising lower costs, as it currently provides cheaper fixed and variable tariffs. However, its lower service scores and higher exit fees place it behind Octopus Energy in overall metrics.
- Higher Trustpilot and Citizens Advice scores
- Highly rated apps with a large user base
- Offers 100% zero-carbon electricity
- Higher prices on its cheapest fixed and variable tariffs
- Phone lines closed at weekends
- Cheaper fixed and variable tariffs
- Faster average call centre wait times
- Responds to more emails within two days
- Lower Citizens Advice score
- Higher exit fee on its cheapest fixed deal
- Higher proportion of one-star Trustpilot reviews
Frequently asked questions
Which supplier is better overall?
Octopus Energy performs better across most independent metrics, including Trustpilot, Citizens Advice, and Which? scores. However, So Energy currently offers cheaper fixed and variable tariffs.
Which supplier has the cheaper fixed tariff?
So Energy offers the cheaper fixed deal. Its So Elk 24m tariff costs £1,638 a year and fixes prices for 24 months. Octopus Energy's cheapest fixed deal costs £1,697 a year and lasts for 12 months.
Do customers prefer Octopus Energy or So Energy?
Octopus Energy has higher customer satisfaction scores. It holds a 4.8 Trustpilot rating with 90% five-star reviews, while So Energy scores 4.5 and has a higher share of one-star reviews.
Are the Octopus Energy and So Energy apps easy to use?
Yes, both suppliers offer highly rated apps. Octopus Energy scores 4.8 on the App Store with a much larger user base, while So Energy scores slightly higher on Google Play, though from fewer ratings.
Which supplier answers the phone faster?
So Energy answers calls slightly faster, with an average wait time of 1 minute 6 seconds compared to 1 minute 17 seconds for Octopus Energy, according to Citizens Advice data.
Should I switch to Octopus Energy or So Energy?
If you want the cheapest possible price, So Energy currently offers lower rates. If you prefer a supplier with strong customer service and independent review scores, Octopus Energy is the better choice.
Do Octopus Energy and So Energy charge exit fees?
Yes, both suppliers charge exit fees on their fixed tariffs. So Energy charges £190 on its cheapest fixed deal, while Octopus Energy charges £100. Flexible Octopus has no exit fee, while So Green Tracker has a £100 exit fee.
What do Which? scores say about these suppliers?
Octopus Energy scores 74 out of 100 in the annual Which? survey and is a Recommended Provider. So Energy scores 60 out of 100.
What are the opening hours for Octopus Energy and So Energy?
Both suppliers are closed at the weekend. Octopus Energy is open Monday to Thursday from 9am to 5pm, and Friday from 9am to 4pm. So Energy is open on weekdays from 9am to 5pm.
What changed this month
This month, So Energy's cheapest tariff term changed from a variable tariff to a 24-month fixed deal, Octopus Energy's cheapest tariff term changed from a variable tariff to a 12-month fixed deal, and So Energy's iOS app days since last update rose from 8 to 22. There were 37 other data changes this month — see the full changelog below for details.
Data changes this month (46)
Octopus Energy
- Trustpilot reviews807,247 → 821,111
- iOS app ratings count244,000 → 245,000
- iOS app days since last update25 → 9
- Play Store rating4.4444447 → 4.4341745
- Play Store ratings count46,777 → 46,873
- Play Store days since last update25 → 11
- Play Store positive ratings %87 → 86.7
- Play Store negative ratings %9.8 → 10
- Play Store neutral ratings %3.2 → 3.3
- Play Store net-positive %77.2 → 76.7
- Citizens Advice rank3 → 4
- Citizens Advice score3.78 → 3.67
- Complaints per 10,000 customers21.8 → 21.3
- Avg call centre wait time72 → 77
- Emails responded within 2 days %90.4 → 86.1
- Cheapest variable tariff£1,566.25 → £1,792.32
- Cheapest fixed tariff£1,691.36 → £1,697.05
- Cheapest tariff£1,566.25 → £1,697.05
- Cheapest tariff exit fee£0 → £100
- Cheapest tariff termvariable → 12 months
So Energy
- Trustpilot reviews29,346 → 29,771
- iOS app ratings count165 → 170
- iOS app days since last update8 → 22
- iOS sampled reviews avg starsnow available (3.8)
- iOS sampled positive reviews0 → 3
- iOS sampled negative reviews0 → 2
- Play Store rating4.6237626 → 4.6
- Play Store ratings count105 → 118
- Play Store days since last update24 → 22
- Play Store negative ratings %4.8 → 4.3
- Play Store neutral ratings %3.8 → 4.3
- Play Store net-positive %86.5 → 87
- Citizens Advice rank11 → 12
- Citizens Advice score2.7 → 2.86
- Complaints per 10,000 customers64.2 → 57.1
- Avg call centre wait time90 → 66
- Avg social media response timenow available (351)
- Emails responded within 2 days %86.8 → 91.3
- Cheapest variable tariff£1,582.51 → £1,744.17
- Cheapest fixed tariff£1,670.24 → £1,637.61
- Cheapest tariff£1,582.51 → £1,637.61
- Cheapest tariff exit fee£0 → £190
- Cheapest tariff termvariable → 24 months
- Tariff count7 → 5
- Fixed tariffs available6 → 3
- Variable tariffs available1 → 2
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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.