How the scores are worked out
We compare energy suppliers' customer service by looking at data from a number of reliable sources. We publish data about suppliers with more than 25,000 customer accounts.
Data about complaints to third parties
We base our ratings on complaints made to:
the Citizens Advice Consumer Service
the Extra Help Unit
the Energy Ombudsman
Data about customer service, billing and switching
We use data from suppliers to work out:
- their average call centre wait time - except time spent in sales lines
- the number of emails they answered within 2 working days
- their average response time for messages on social media - where they’re contacted more than 5% of the time through social media
- the number of their customers who got a bill based on a meter reading in the past year - except prepayment customers
- the number of switches completed within 15 working days of agreeing the contract
Data about customer guarantees
We base our ratings on suppliers’ membership of the Energy Switch Guarantee and the Vulnerability Commitment.
If a supplier is a member of the Energy Switch Guarantee, they have to meet certain criteria - such as completing 98% of switches within 21 days. Find out more about the Energy Switch scheme on the Energy Switch Guarantee website.
If a supplier is a member of the Vulnerability Commitment, they have to promise to improve their support to vulnerable customers, who might be facing financial difficulties or illnesses. Find out more about the Vulnerability Commitment on the Energy UK website.
Suppliers score 3 points for membership of the Energy Switch Guarantee or the Vulnerability Commitment. If they're a member of both, their score is capped at 5 points. Trial members of the Energy Switch Guarantee score 2 points.
If we don't have data for your supplier
Suppliers are legally required to share the data we use in this rating. They also need to have a referral system to our consumer service.
If they don’t, we score them zero in categories related to these things.
We need suppliers to give us permission to publish data they share with us. If they don’t, you’ll only see a star rating.
How we come up with a star rating
We give energy suppliers a score out of 5 for each category. 5 is excellent and 1 is poor. Then we give them an overall star rating out of 5.
|Number of complaints per 10,000 customers||5 or less||5 to 15||15 to 30||30 to 55||More than 55|
|Average call centre wait time (seconds)||Less than 30s||30s - 90s||90s - 180s||180s - 300s||More than 300s|
|Emails responded to within 2 working days||More than 95%||95 - 80%||80 - 60%||60 - 40%||Less than 40%|
|Average social media response time||Less than 30 mins||30 - 60 mins||1 - 2 hours||2 - 4 hours||More than 4 hours|
|Switches completed within 15 working days||More than 98%||95 - 98%||90 - 95%||80 - 90%||Less than 80%|
|Customers who had accurate bill in the past year|
Suppliers score 3 points each for membership of the Energy Switch Guarantee and membership of the Vulnerability Commitment (up to a maximum of 5 points). Trial members of the Energy Switch Guarantee score 2 points.
Not all categories are equal. Some, like complaints, count more towards the final score than others.
This is how we work out the overall scores.
|Category||Measured as||Counts towards overall score|
|Complaints to third parties||Complaints to third parties||35%|
|Customer service||Average call centre wait time||15%|
|Email response time||10% or 5% if they’re also scored on social media response time|
|Social media response time - if contacted more than 5% of the time through social media||5%|
|Switching||Switches completed within 15 working days||10%|
|Customer guarantees||Membership of a range of schemes||10%|
To measure bill accuracy, suppliers must have been supplying more than 5,000 customer accounts for 12 months.
Some suppliers have mostly customers who pay by prepayment. Suppliers with fewer than 5,000 billed customers do not receive a billing score, and are scored on the other categories only.