100Green OVO Energy (September 2026)
Overview
There is no single best choice: compare price, service, app and green-energy evidence separately.
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Tariffs and pricing
Annual estimates use the stored consumption assumptions. Check current regional rates, terms and eligibility before switching.
Customer reviews
Each review service uses its own method and scale, so the measures below should be read separately.
App quality and ratings
App-store scores are shown by platform. No winner is declared where either ratings sample is missing or too small.
Service and support
Only like-for-like service measures with data for both suppliers are ranked.
Complaints and performance
Complaint figures are shown with each supplier’s reporting period. No winner is declared when periods differ or one figure is missing.
Green Energy Comparison
Published fuel-mix figures are shown only where both a source URL and reporting period are present in the stored data.
Our verdict
| If you care most about | Choose |
|---|---|
| The lowest annual cost on our assumptions | OVO Energy |
| Overall customer service | 100Green |
| A greener fuel mix | 100Green |
There is no single best choice: compare price, service, app and green-energy evidence separately.
Use the decision table to match the available evidence to the factors that matter most to your household.
- Cheapest variable tariff at £1,762 / year
- 4.6 Trustpilot from 1,559 reviews
- Top-1 Citizens Advice ranking
- 91% of emails answered within 2 days
- 94% of Google Play ratings are negative
- Cheapest variable tariff at £1,611 / year
- 4.7 Trustpilot from 299,269 reviews
- iOS app rated 4.6 out of 5
- 99% of emails answered within 2 days
- 52% of Google Play ratings are negative
Frequently asked questions
Which is cheaper, 100Green or OVO Energy?
On the stored annual-cost assumptions, 100Green is £1,717 and OVO Energy is £1,611. OVO Energy is lower by about £106 a year.
Can 100Green and OVO Energy complaint rates be compared directly?
No direct complaint-rate winner is declared because 100Green and OVO Energy do not both have figures for the same stated reporting period.
Which supplier leads on customer service?
On the comparable customer-service measure used in the decision table, 100Green leads.
Which supplier has the better app evidence?
The supplied data does not support a like-for-like app winner.
Do tariff eligibility rules matter?
Yes. Specialist, time-of-use, EV, heat-pump and export tariffs can have equipment, meter or account requirements. Check the current supplier terms before applying.
Which supplier has the greener evidence?
On the comparable green-energy measure used in the decision table, 100Green leads. This row is based on published fuel-mix percentages.
Which is better overall, 100Green or OVO Energy?
There is no single overall winner in this repaired draft. Price, service, app and green-energy evidence are kept as separate choices in the decision table.
When was this comparison updated?
The structured source payload is for September 2026.
What changed this month
This month, OVO Energy's play store net-positive % fell from 1.3 to -9.2, 100Green's iOS app days since last update fell from 38 to 25, and OVO Energy's iOS app days since last update fell from 37 to 25. There were 26 other data changes this month — see the full changelog below for details.
Data changes this month (32)
100Green
- Trustpilot reviews1,539 → 1,559
- Trustpilot 4-star %12 → 11
- Trustpilot 1-star %7 → 8
- Trustpilot positive reviews %86 → 85
- Trustpilot negative reviews %10 → 11
- Trustpilot net-positive %76 → 74
- iOS app days since last update38 → 25
- Play Store rating1.2413793 → 1.2258065
- Play Store ratings count30 → 32
- Play Store days since last update38 → 26
- Play Store positive ratings %3.4 → 3.2
- Play Store negative ratings %93.1 → 93.5
- Play Store neutral ratings %3.4 → 3.2
- Play Store net-positive %-89.7 → -90.3
- Avg social media response timenow available (55)
- Cheapest variable tariff£1,975.79 → £1,761.9
- Cheapest fixed tariff£1,748.8 → £1,717.28
- Cheapest tariff£1,748.8 → £1,717.28
OVO Energy
- Trustpilot reviews293,863 → 299,269
- Trustpilot 5-star %77 → 78
- Trustpilot 4-star %10 → 9
- iOS app days since last update37 → 25
- Play Store rating3.0206423 → 2.8167422
- Play Store ratings count10,621 → 10,825
- Play Store days since last update37 → 26
- Play Store positive ratings %48.2 → 43.2
- Play Store negative ratings %46.9 → 52.4
- Play Store neutral ratings %4.9 → 4.4
- Play Store net-positive %1.3 → -9.2
- Cheapest variable tariff£1,804.82 → £1,610.88
- Cheapest fixed tariff£1,923.42 → £1,742.03
- Cheapest tariff£1,804.82 → £1,610.88
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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.