Iresa Energy has been named the worst energy company for customer service amid record complaint levels.

The latest energy star rating table by Citizens Advice ranks Iresa bottom with a score of 0.35 stars out of five for its customer service between January and March 2018.

It had more than 9,000 complaints per 100,000 customers – the worst-ever complaints score recorded by Citizens Advice.

The score is five times higher than the next worst supplier, Toto Energy, which received 1,800 complaints. Toto was criticised earlier this year for transferring customers to Utilita Energy without adequate communication.

Iresa could imminently face an extension on the ban that prevents it taking on new customers or even have its licence revoked if it fails to convince Ofgem it has got its “house in order”.

The company has been unable to take on new customers since March due to the provisional order from Ofgem. It is also subject to a separate longer-term investigation by the regulator, which launched in February.

Citizens Advice suggest the failings of small energy suppliers reveal flaws in the regulation of the industry and demonstrate the need for Ofgem to “tighten” its licensing rules.

Gillian Guy, chief executive of Citizens Advice, said: “Iresa’s low score will come as no surprise for its customers, who have had to put up with continued problems. These include inaccurate billing, long phone queues and even being blocked from switching to a new supplier.

“It’s vital now that Ofgem does more to protect consumers from poor customer service. The regulator’s upcoming review of licensing rules must do two things: make it easier to stop unprepared suppliers from entering the market and take poorly performing companies out of the market faster.”

Other companies near the bottom of the table include Robin Hood Energy, Avro Energy and Spark Energy.

At the other end of the scale, So Energy came top of the class for the second consecutive quarter with a score of 4.8 stars.

SSE was the best performing of the largest six energy suppliers, scoring 4.25 stars out of five.

Rob Salter-Church, Ofgem interim executive director, said: “All suppliers must provide customers with good service, including acting quickly and effectively to sort things out wherever problems occur. Where suppliers fail to do so, Ofgem will step in and take strong action.

“We have already imposed a provisional order on Iresa and have warned them that its licence could be revoked unless it puts its house in order.

“We recently began a review of our approach to licensing suppliers to ensure that appropriate protections are in place against poor customer service and financial instability and will update on progress in late summer.”

Lewis Shand Smith, chief Ombudsman at Ombudsman Services, said: “We’ve received a growing number of complaints about Iresa over the past 12 months. As with any supplier we see struggling to manage complaints, we have been helping Iresa to improve its processes and we have been actively informing Ofgem of the issues and progress made.

“We will continue to support Iresa with its efforts to improve customer service and reduce consumer detriment, but understand that this is a frustrating time for any current customers.”

Iresa declined to comment.

Supplier Star rating January to March 2018
So Energy 4.8
Engie 4.3
E (Gas and Electricity) 4.3
SSE 4.25
British Gas 4.1
Bristol Energy 4.05
Green Network Energy 4.05
Bulb Energy 3.85
EDF Energy 3.85
Tonik Energy 3.85
Octopus Energy 3.8
Ovo Energy 3.55
Utility Warehouse 3.45
First Utility 3.4
Npower 3.4
Scottish Power 3.3
Co-operative Energy 3.2
Flow Energy 3.1
Eon 2.95
Ecotricity 2.95
PFP Energy 2.85
Good Energy 2.55
iSupply 2.4
Economy Energy 2.3
Extra Energy 2.3
Green Star Energy 2.2
Utilita 2.2
Spark Energy 2
Avro Energy 1.7
Robin Hood Energy 1.7
Toto Energy 1.6
Iresa 0.35

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