Octopus Energy So Energy (August 2026)
Overview
Octopus Energy is our recommended supplier for its outstanding customer service and highly rated apps, though So Energy currently offers cheaper tariffs.
Octopus Energy scores higher across the customer service and app metrics in this comparison, including ratings from Citizens Advice and Which?. So Energy currently provides cheaper fixed and variable tariffs, which may suit households prioritising upfront costs, though Octopus performs better across broader service categories.
About Octopus Energy and So Energy
Who are Octopus Energy?
Octopus Energy started in 2015 with backing from Octopus Group. Led by founder Greg Jackson, the company grew quickly by building its own billing and customer service platform called Kraken. Today, it is the UK's largest energy supplier. It focuses on smart technology and zero-carbon energy. What sets it apart is its wide range of smart tariffs, which reward customers for using energy at cheaper, greener times of day.
Who are So Energy?
So Energy launched in 2015 as an independent supplier focused on green energy. In 2021, ESB, the Irish state electricity company, acquired a majority stake in So Energy, which then merged with ESB Energy. Today, it is one of the UK's domestic energy suppliers. It focuses on simple pricing and renewable power. What sets it apart is that it lets customers vote on which types of renewable energy the company buys, such as wind, solar, hydro, or biomass.
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Tariffs and pricing
So Energy provides the lowest-priced tariff in this comparison. Its variable So Green Tracker 24m costs £1,687 a year, requiring a 24-month contract and a £190 exit fee. In contrast, Octopus Energy’s most affordable option is the Flexible Octopus variable tariff at £1,792 a year, which operates without a fixed term or exit fees.
For households seeking fixed rates, So Energy again offers the cheaper option. The So Heron 18m tariff is priced at £1,829 a year, carrying an 18-month term and a £190 exit fee. Octopus Energy’s lowest-priced fixed alternative, the Octopus 12M Fixed July 2026 v5, costs £1,841 annually on a 12-month contract with a £100 exit fee.
Tariff Options
Octopus Energy
Octopus Energy offers standard variable and fixed-term energy plans. It also provides smart and specialist tariffs designed for households with electric vehicles, heat pumps, or solar panels.
So Energy
So Energy provides standard variable and fixed-term tariffs. It also offers smart and specialist options for households with electric vehicles or those wanting personalised rates based on their energy use.
Customer reviews
On Trustpilot, Octopus Energy holds a 4.8-star rating based on 837,814 reviews. It secures a 90% five-star share, with 3% of users leaving a one-star rating. Feedback often highlights helpful staff and quick responses, although some customers report delays regarding email replies.
So Energy maintains a 4.5-star rating across 30,220 Trustpilot reviews. This includes a 73% five-star share and a 12% one-star share. While users note competitive pricing and helpful staff, a portion of reviews cite billing issues and inconsistent information.
In the annual Which? energy survey, Octopus Energy scores 74 out of 100, ahead of So Energy’s 60. Octopus receives 10 out of 10 for helping those who need it, whereas So Energy scores 7 out of 10. Furthermore, Octopus scores 8 out of 15 for complaints handling (compared to So Energy's 5 out of 15) and 5 out of 10 for smart meters (compared to So Energy's 2 out of 10).
App quality and features
Octopus Energy records over 1,000,000 installs on Google Play and 249,000 ratings on the App Store. The software scores 4.8 on iOS and 4.4 on Google Play. Recent iOS feedback is mixed; some users highlight the interface's simplicity, while others experience difficulties with billing and meter reading submissions.
So Energy's app scores 4.7 on iOS and 4.6 on Google Play, though these figures stem from smaller samples of 197 and 127 ratings, respectively. This lower volume makes direct comparison with Octopus Energy's extensive feedback difficult. Recent updates to the So Energy app have focused on general bug fixes and improvements.
Customer service and support
Citizens Advice data shows Octopus Energy scoring 3.67 out of 5, placing it 4th overall. So Energy ranks 12th with a score of 2.86 out of 5. Both companies maintain formal vulnerability commitments registered with Citizens Advice to assist households requiring additional support.
Call centre wait times are comparable between the two providers. So Energy averages 1 minute 6 seconds, while Octopus Energy averages 1 minute 17 seconds. For written communication, So Energy responds to 91.3% of emails within two days, compared to 86.1% for Octopus.
So Energy reports an average social media response time of 5 minutes 51 seconds; equivalent data is not currently available for Octopus Energy. Both suppliers keep their main phone lines open on weekdays and closed during the weekend.
Complaints and performance
Both suppliers' figures cover the first quarter of 2026. Octopus Energy received far fewer complaints than So Energy, with 538 complaints per 100,000 customers compared to So Energy's 1,573.
When it comes to fixing problems, So Energy was slightly faster. It solved 46% of complaints by the end of the next working day, while Octopus Energy solved 43%. So Energy also resolved more complaints within eight weeks, reaching 88% compared to 80% for Octopus Energy.
Why do customers complain?
For Octopus Energy, the main reason for complaints was customer service. To help with this, the supplier has grown its teams and set up a training academy for its staff. Other common complaints were about billing, payment issues, and smart meters. To help customers struggling with payments, Octopus Energy has put £40 million into a support fund.
So Energy's most common complaints were about payment issues, which made up 24% of its total. Customer service and billing issues were also common reasons for customers to complain. Debt and debt-related disconnections made up 13% of its complaints.
Octopus Energy wins this category because it receives far fewer complaints overall, even though So Energy is slightly faster at resolving the complaints it does get.
Green Energy Comparison
Octopus Energy
Octopus Energy supplies 100% zero-carbon electricity as standard. Based on Citizens Advice data from early 2026, its overall fuel mix is largely renewable, with some nuclear. The company invests heavily in green projects. Its generation arm manages £6,800 million in renewable assets, including wind and solar farms. It is also investing around £390 million in US forestry projects to remove carbon from the atmosphere. On top of this, it runs a 'Zero Bills' scheme, which guarantees no energy bills for homes built with specific green technology.[1]
So Energy
So Energy promises 100% renewable electricity on all its fixed-rate tariffs. Based on Citizens Advice data from early 2026, its overall fuel mix is mostly renewable, with some fossil fuels and a small amount of nuclear and other sources. The company supports the shift to net zero by helping customers install green technology at home, such as solar panels and electric vehicle chargers.[2]
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 is our recommended supplier for its outstanding customer service and highly rated apps, though So Energy currently offers cheaper tariffs.
Octopus Energy performs better across the majority of metrics in this comparison, leading in customer reviews, Citizens Advice scores, and app ratings. So Energy provides cheaper fixed and variable tariffs, which may appeal to households focused strictly on price, though its lowest-priced deal requires a 24-month contract and a £190 exit fee.
So Energy may suit households prioritising lower annual costs and who are comfortable with a 24-month contract and exit fees. Conversely, Octopus Energy may be more appropriate for customers who value higher-rated customer service, established app platforms, and flexible variable terms without exit fees.
- Higher Citizens Advice and Which? scores
- 90% five-star share on Trustpilot
- Variable tariff has no exit fees
- More expensive overall and fixed tariffs in this comparison
- Slightly longer average call centre wait time
- Cheaper overall variable tariff
- Cheaper 18-month fixed tariff
- Slightly faster average email response time
- Cheapest tariff carries a £190 exit fee and 24-month term
- Lower Which? and Citizens Advice scores
- App ratings based on very small samples
Frequently asked questions
Which supplier is better overall?
Octopus Energy ranks higher across most of our metrics, particularly in customer service, Trustpilot reviews, and app quality. However, So Energy currently offers cheaper tariffs for households focused purely on price.
Which supplier has the cheapest energy tariff?
So Energy offers the cheapest deal in our comparison with its So Green Tracker 24m variable tariff. However, this comes with a 24-month contract and a £190 exit fee. Octopus Energy's cheapest option is slightly more expensive but has no exit fees.
What do customers say about Octopus Energy and So Energy?
Octopus Energy holds a 4.8-star rating on Trustpilot, with customers frequently praising its helpful staff and quick responses. So Energy has a 4.5-star rating, with positive feedback on pricing but some reports of inconsistent communication.
Are the Octopus Energy and So Energy apps any good?
Octopus Energy's app is highly rated on both iOS and Android, backed by hundreds of thousands of reviews. So Energy's apps also score well, but these ratings are based on fewer than 200 reviews, making them harder to compare.
How quickly do Octopus Energy and So Energy answer the phone?
Both suppliers answer calls quickly. So Energy has an average wait time of 1 minute 6 seconds, while Octopus Energy averages 1 minute 17 seconds according to Citizens Advice.
Should I switch to Octopus Energy or So Energy?
If you want the cheapest available rates and do not mind committing to a longer contract with exit fees, So Energy is a strong option. If you prefer highly rated customer service and no exit fees on variable deals, choose Octopus Energy.
Do these suppliers charge exit fees?
It depends on the tariff. So Energy charges a £190 exit fee on its cheapest variable and fixed deals. Octopus Energy's cheapest variable tariff has no exit fees, but its fixed deals carry a £100 exit fee.
Do Octopus Energy and So Energy offer support for vulnerable customers?
Yes, both Octopus Energy and So Energy have formal vulnerability commitments registered with Citizens Advice to support households that need extra help.
How do the suppliers compare in the Which? energy survey?
Octopus Energy scores 74 out of 100 in the Which? survey, with top marks for helping those who need it. So Energy scores 60 out of 100, ranking lower for complaints handling and smart meter support.
Which supplier is greener?
Octopus Energy provides 100% zero-carbon electricity as standard, made up of renewable and nuclear power. So Energy also focuses on renewables, but its overall fuel mix includes around 27% fossil fuels.
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 Octopus Energy's iOS sampled positive reviews rose from 0 to 1. There were 29 other data changes this month — see the full changelog below for details.
Data changes this month (40)
Octopus Energy
- Trustpilot reviews821,111 → 837,814
- iOS app ratings count245,000 → 249,000
- iOS app days since last update9 → 6
- iOS sampled reviews avg starsnow available (2)
- iOS sampled positive reviews0 → 1
- iOS sampled negative reviews0 → 2
- Play Store rating4.4341745 → 4.3956046
- Play Store ratings count46,873 → 47,091
- Play Store days since last update11 → 2
- Play Store positive ratings %86.7 → 85.5
- Play Store negative ratings %10 → 11
- Play Store neutral ratings %3.3 → 3.5
- Play Store net-positive %76.7 → 74.5
- Cheapest fixed tariff£1,697.05 → £1,841.19
- Cheapest tariff£1,697.05 → £1,792.32
- Cheapest tariff exit fee£100 → £0
- Cheapest tariff term12 months → 0 months
- Tariff count2 → 3
- Fixed tariffs available1 → 2
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.