How the scores are worked out
We compare energy suppliers' customer service by looking at information from a number of reliable sources.
Information about complaints to third parties
We base our ratings on complaints made to:
- Citizens Advice Consumer Service
- the Extra Help Unit
- the Energy Ombudsman
Information on complaints is only available for suppliers with 50,000 customers or more.
Information about other categories
- customer service and billing comes from the GFK market research survey
- switching comes from Ofgem and suppliers themselves
This information is only available for suppliers with 150,000 customers or more.
Information on the Switching Guarantee comes from Energy UK.
How we come up with a star rating
We give energy suppliers a score out of 5 for each category. 1 is poor and 5 is excellent. Then we give them an overall star rating out of 5.
|Number of complaints per 100,000 customers||50 or less||51 to 100||101 to 350||351 to 550||More than 550|
|Customers who found contacting supplier easy||More than 75%||70-75%||60-69%||51-59%||50% or less|
|Customers who found bills easy to understand||More than 75%||70-75%||60-69%||51-59%||50% or less|
|Switches done in 21 days||98%||90-97%||75-89%||50-74%||Less than 50%|
|Signed up to Switch Guarantee||Suppliers score a 5 if they’re signed up and a zero if they're not.|
Not all categories are equal. Some, like complaints, count more towards the final score than others.
This is because we think the number of complaints a supplier gets is the best indicator of how good their customer service is.
This is how the overall scores are worked out.
|Category||Maximum category score||Counts towards overall score||Stars towards overall rating|
|Complaints to third parties||5 stars||30%||1.5 stars|
|Ease of contact||5 stars||25%||1.25 stars|
|Billing clarity||5 stars||25%||1.25 stars|
|Ease of switching||5 stars||15%||0.75 stars|
|Switch Guarantee||5 stars||5%||0.25 stars|