100Green E.ON Next (August 2026)
Overview
This is a close comparison: choose E.ON Next for its app experience and lower-priced tracker, or 100Green for stronger customer service and 100% green energy.
E.ON Next edges ahead overall due to its highly rated apps and a significantly cheaper tracker tariff. 100Green performs better on customer service metrics, ranking first in Citizens Advice data, and offers 100% green gas and electricity for households willing to pay a premium.
About 100Green and E.ON Next
Who is 100Green?
100Green is an independent energy supplier based in Hertfordshire. Set up in 2001 as Green Energy UK, it is one of the UK's oldest green energy suppliers. The family-run business chooses to grow at a pace that matches its green energy supply rather than chasing a large market share. What sets it apart is that it offers 100% green gas as standard alongside renewable electricity. It also uses in-house staff to answer phone calls instead of automated systems or chatbots.
Who are E.ON Next?
E.ON Next is the retail brand of E.ON UK, which is owned by the German energy group E.ON SE. Launched in 2020 to replace the legacy E.ON brand and take on customers from npower, it is now one of the UK's largest energy suppliers. It runs its customer service on the Kraken platform to help manage accounts. The company offers a wide range of tariffs, as well as discounts on home energy technology such as solar panels, heat pumps, and electric vehicle chargers.
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Tariffs and pricing
The cheapest deals from both suppliers are effectively identical under our assumptions, showing an annual difference of just £3. 100Green's lowest-priced option is the Exclusive Spring 100% Green 12M August 27, a 12-month fixed tariff at £1,749 a year with no exit fees. In comparison, E.ON Next's cheapest deal is the Next Fixed 24m v57, a 24-month fixed tariff costing £1,746 a year, which carries a £200 exit fee.
For households looking beyond fixed deals, E.ON Next is notably cheaper. Its Next Pledge Tracker 12m v12 tracker tariff costs £1,747 a year, requiring a 12-month term and a £50 exit fee. Conversely, 100Green's Sparkling SVT standard variable tariff costs £1,976 a year, though it has no fixed term and no exit fee.
Tariff Options
100Green
100Green offers standard variable and fixed-rate tariffs, alongside a range of specialist options for electric vehicles and homes with flexible energy habits.
E.ON Next
E.ON Next provides standard variable and fixed tariffs, as well as tracker tariffs and specialist plans for electric vehicles, heat pumps, and solar panels.
Customer reviews
Both suppliers maintain strong Trustpilot scores. 100Green holds a 4.6 out of 5 rating based on a low volume of 1,539 reviews, with 74% of customers awarding five stars. E.ON Next has a 4.5 out of 5 rating from a much larger volume of 219,212 reviews, matching the 74% five-star share.
Review summaries indicate that 100Green customers appreciate helpful staff and quick responses during interactions. E.ON Next users frequently highlight polite and efficient issue resolution, although some reviewers mention concerns regarding pricing and incorrect advice.
In the annual Which? survey, 100Green achieves 72 out of 100, while E.ON Next scores 66 out of 100. 100Green leads on customer service, scoring 4 out of 5 compared to E.ON Next's 2 out of 5. It also performs better in complaints handling, receiving 12 out of 15 versus E.ON Next's 8 out of 15.
However, E.ON Next scores highly for helping those who need it, achieving 9 out of 10, whereas 100Green scores 4 out of 10 in this category. E.ON Next also leads on smart meters, scoring 8 out of 10 compared to 100Green's 6 out of 10. Both suppliers show weakness in the switching process, where 100Green receives just 1 out of 5 and E.ON Next receives 2 out of 5.
Apps and digital experience
E.ON Next provides highly rated applications across both major platforms. Its iOS app scores 4.8 out of 5 from 49,000 ratings, and the Google Play version holds a 4.3 out of 5 rating from 16,070 ratings. Recent iOS release notes for E.ON Next indicate recent updates focused on bug fixes and performance enhancements.
100Green's apps record very low scores, although these stem from small sample sizes. The iOS app has a 1.1 out of 5 rating from 21 ratings, while the Google Play app scores 1.2 out of 5 from 30 ratings. Because these samples fall below 50 ratings, they are difficult to compare directly against a supplier with tens of thousands of reviews and may not fully reflect current overall quality. Recent sampled feedback for 100Green suggests the app is basic and difficult to use.
Service and support
100Green ranks 1st in the Citizens Advice table with an overall score of 4.33 out of 5. E.ON Next also performs well, ranking 3rd with a score of 3.71 out of 5. Both suppliers respond to approximately 91% of emails within two days, and each maintains formal vulnerability commitments registered with Citizens Advice.
For telephone support, 100Green answers calls in an average of just 7 seconds. E.ON Next takes longer, recording an average wait time of 2 minutes 3 seconds. 100Green operates its phone lines on weekends from 9am to 1pm, whereas E.ON Next is closed on Saturdays and Sundays.
Complaints and performance
Both suppliers have shared their complaints data for the first quarter of 2026. 100Green received 144 complaints for every 100,000 customers. E.ON Next received 780 complaints for every 100,000 customers.
We do not have data to show how quickly 100Green fixes complaints. E.ON Next sorted out 50.6% of its complaints by the end of the next working day. It fixed 90.5% of complaints within eight weeks.
Main reasons for complaints
100Green has not published the main reasons why its customers complain. E.ON Next lists its top five reasons for complaints as:
- Customer service (33.87%)
- Payments (13.7%)
- General billing and meter reading issues (11.82%)
- Debt and debt-related disconnections (8.49%)
- Smart billing and meter reading issues (7.32%)
Green Energy Comparison
100Green
100Green supplies a 100% renewable electricity mix. Rather than just buying certificates to match the energy its customers use, the supplier buys power directly from independent UK renewable generators, including wind, solar, and hydro sites. It also supplies 100% green gas made from organic waste through anaerobic digestion, rather than offsetting fossil gas. Every unit of its green gas is certified by the Green Gas Certification Scheme.
E.ON Next
E.ON Next supplies a mostly renewable electricity mix, with some fossil fuels and a small amount of nuclear and other sources. It offers 100% renewable electricity through its Next Gust tariff, backed by Renewable Energy Guarantees of Origin (REGO) certificates alongside some direct supply agreements. For customers wanting a dedicated green option, it offers a specific tariff backed by UK wind generators. The company also invests in local decarbonisation projects and partners with the Woodland Trust to support ancient woodlands.[1]
Our verdict
| If you care most about | Choose |
|---|---|
| The lowest annual cost on our assumptions | Either |
| Overall customer service | 100Green |
| A well-rated mobile app | E.ON Next |
| A greener fuel mix | 100Green |
This is a close comparison: choose E.ON Next for its app experience and lower-priced tracker, or 100Green for stronger customer service and 100% green energy.
E.ON Next may suit households looking for a digital-first experience, offering highly rated mobile apps and a tracker tariff that is significantly cheaper than 100Green's variable option. While its customer service wait times are longer, it still performs well enough to rank 3rd in Citizens Advice data.
Alternatively, 100Green may appeal to those who prioritise customer service and environmental benefits. It ranks 1st in the Citizens Advice table, answers calls in an average of just 7 seconds, and supplies 100% green gas and electricity, which may justify the higher variable rates for some customers.
Households seeking lower variable prices and a well-rated app experience may find E.ON Next more suitable. Those who prefer to avoid exit fees on fixed deals and prioritise a strong customer service record may find 100Green to be the better option.
- Ranks 1st in Citizens Advice data
- Average call wait time of just 7 seconds
- Offers 100% green gas and electricity
- No exit fees on its cheapest fixed tariff
- Variable tariff is significantly more expensive
- App ratings are very low, though based on a small sample
- Scores lower on Which? for helping those who need it
- Much cheaper tracker and variable options
- Highly rated apps on both iOS and Android
- Ranks 3rd in Citizens Advice data
- Scores 9 out of 10 for helping those who need it (Which?)
- £200 exit fee on its cheapest fixed tariff
- Customer service phone lines are closed at weekends
- Longer average call wait time than 100Green
Frequently asked questions
Which supplier is better overall, 100Green or E.ON Next?
This is a close comparison. E.ON Next may suit households prioritising highly rated mobile apps and a lower-priced tracker, while 100Green may suit those prioritising top-ranked customer service and 100% green energy.
How do the fixed tariffs compare between 100Green and E.ON Next?
The cheapest fixed deals from both suppliers are effectively identical under our assumptions. 100Green's cheapest fixed option costs £1,749 a year for 12 months with no exit fees. E.ON Next offers a 24-month fixed deal at £1,746 a year, which carries a £200 exit fee.
What do Trustpilot reviews say about 100Green and E.ON Next?
Both suppliers receive strong feedback on Trustpilot. 100Green has a 4.6 out of 5 rating, with customers praising its helpful staff and service. E.ON Next scores 4.5 out of 5, with many reviewers highlighting polite and efficient staff, though some mention concerns about pricing and incorrect advice.
Are the E.ON Next and 100Green apps easy to use?
E.ON Next offers highly rated apps, scoring 4.8 out of 5 on iOS and 4.3 out of 5 on Android. 100Green's apps receive very low ratings of 1.1 out of 5 on iOS and 1.2 out of 5 on Android, though these scores are based on very small samples of under 50 ratings each.
Which supplier answers the phone faster, 100Green or E.ON Next?
100Green is much faster at answering calls, with an average wait time of just 7 seconds according to Citizens Advice data. In contrast, E.ON Next customers wait an average of 2 minutes 3 seconds.
Should I choose 100Green or E.ON Next?
If you want the cheapest variable tariff and highly rated mobile apps, E.ON Next is the better choice. However, if you value a strong customer service record, short call wait times, and 100% green gas, 100Green is an excellent option.
Do 100Green and E.ON Next charge exit fees?
This depends on the tariff. 100Green's cheapest fixed tariff has no exit fees. E.ON Next's cheapest fixed deal carries a £200 exit fee, and its tracker tariff has a £50 exit fee.
Do 100Green and E.ON Next open on weekends?
100Green opens its customer service lines on Saturdays and Sundays from 9am to 1pm. E.ON Next is closed on weekends, with phone lines open Monday to Thursday from 9am to 5pm, and Friday from 9am to 4pm.
Do 100Green and E.ON Next offer green energy?
Yes. 100Green offers 100% renewable electricity and 100% green gas as standard on all its tariffs. E.ON Next provides 100% renewable electricity as standard for homes, and also offers a specific fixed tariff backed entirely by UK wind energy.
Do 100Green and E.ON Next support smart meters?
Yes, both suppliers support smart meters. In the annual Which? survey, E.ON Next scores 8 out of 10 for its smart meter service, while 100Green scores 6 out of 10.
What changed this month
This month, 100Green's play store days since last update rose from 15 to 38, 100Green's iOS app updates in last 90 days rose from 0 to 3, and E.ON Next's iOS sampled positive reviews fell from 1 to 0. There were 18 other data changes this month — see the full changelog below for details.
Data changes this month (28)
100Green
- Trustpilot reviews1,511 → 1,539
- iOS app ratingnow available (1.1)
- iOS app ratings countnow available (21)
- iOS app days since last updatenow available (38)
- iOS app updates in last 90 days0 → 3
- iOS sampled reviews avg starsnow available (1)
- iOS sampled negative reviews0 → 3
- Play Store days since last update15 → 38
- Avg social media response time55 → no longer available
- Cheapest fixed tariff£1,671.16 → £1,748.8
- Cheapest tariff£1,671.16 → £1,748.8
E.ON Next
- Trustpilot reviews211,533 → 219,212
- iOS app ratings count48,000 → 49,000
- iOS app days since last update9 → 4
- iOS sampled positive reviews1 → 0
- iOS sampled negative reviews1 → 0
- iOS sampled neutral reviews0 → 1
- Play Store rating4.3445005 → 4.324643
- Play Store ratings count15,798 → 16,070
- Play Store days since last update9 → 5
- Play Store positive ratings %83.5 → 82.6
- Play Store negative ratings %13.7 → 14.2
- Play Store neutral ratings %2.8 → 3.2
- Play Store net-positive %69.8 → 68.4
- Cheapest fixed tariff£1,733 → £1,745.58
- Cheapest tariff£1,733 → £1,745.58
- Cheapest fixed tariff exit fee£100 → £200
- Cheapest fixed tariff term12 months → 24 months
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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.