Energy provider OneSelect has been named the worst provider in the customer service market.
In its latest classification, which ranks customer service levels of energy providers, Citizens Advice, the giant has failed to satisfy households in terms of service and wait times.
The ratings covered a range of measures, including the number of complaints, waiting times, the speed and accuracy of billing, and the fact that switching occurs on time. It comprised 34 companies (serving approximately 99% of the market).
The results, which cover the period from July to September 2018, revealed that OneSelect had underperformed in all categories.
The company joined the market in 2017 as a "low cost" supplier, supplying gas and electricity to around 35,000 households in England and Wales.
Customers have reported problems contacting the company by phone and only about two thirds of their customers received an invoice based on a meter reading last year.
In the results, So Energy has managed to maintain its top spot for the fourth consecutive quarter with a score of 4.7, while SSE ranks second with 4.4 stars, making it best choice among the 6 biggest suppliers.
Octopus Energy performed well, with a score of 4.3, despite the acquisition of 95,000 customers of the default supplier Iresa during the quarter.
E.ON has the lowest ranking of the top 6 energy suppliers. The company slipped from 18th to 20th place, with a current score of 2.9 out of 5.
Gillian Guy, of Citizens Advice, said: "The future price cap will make a real difference to consumers, but it's certainly not the end of history. It is always important to look for the best deals, but also to know where to get good customer service.
"These ratings show that consumers can not afford to make assumptions about the quality of service of an energy provider based on their size or the strength of their brand."
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