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Energy company reviews


By Sarah Ingrams

Article 16 of 34

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iSupplyEnergy has sold energy to domestic customers since 2012. It says its mission is to 'rebuild trust in an industry that is long overdue a change'.

iSupplyEnergy is based in Bournemouth, Dorset. It has three simple tariffs, including a prepayment option. You can only switch to iSupplyEnergy online.

Previously a British-owned supplier, iSupplyEnergy was bought by European gas and electricity giant Vattenfall in June 2017.

Initially, iSupplyEnergy only offered electricity tariffs. It began supplying gas as well from December 2015. 

iSupplyEnergy also provides 100% renewable electricity. 

You can find out how iSupplyEnergy's prices compare with your current deal by finding the cheapest gas and electricity with Which? Switch now.

iSupplyEnergy customer score

iSupplyEnergy comes in 23rd place out of 35 energy companies rated by 8,355 members of the public in the annual Which? energy supplier satisfaction survey – the biggest of its kind. 

iSupplyEnergy's customer score of 64% is just one percentage point above the average across all 35 companies in our survey (63%). Our top scorer was Octopus Energy, at 83%. Together Energy was last with a customer score of 48%.

iSupplyEnergy score breakdown

The table below shows the breakdown of iSupplyEnergy's score from our latest survey. Keep reading to find out more about what its customers think of it, and to compare iSupplyEnergy's fuel mix with the UK average.

Find out how iSupplyEnergy compares with other energy companieswe reveal the full results of the best and worst energy companies.

Which? verdict on iSupplyEnergy

iSupplyEnergy has competitive rates and customers seemed largely happy with its value for money, receiving a respectable rating of four stars out of five. 

Customer service also received a credible four stars, and a number of customers took the time out to comment on this area. One said: 'I've always received a prompt and helpful response,' while another commented 'they are simple, clear and reliable'.

But it was its billing accuracy that impressed the most: 89% of its customers said it was good or excellent, compared with 83% on average across all companies included. 

However, the clarity of bills didn't fare so well, and was rated just three out of five stars. 

Its digital tools also seem to be a cause for frustration based on customers' comments. However, due to the lack of responses, we are unable to give it a rating. This is the same for complaints handling too. 

It is an online-based company. iSupplyEnergy doesn't offer any live-chat facilities. 

These comments also reflect iSupplyEnergy's published complaints data. Although it received a relatively low number of complaints overall in the first six months of last year, it wasn't the fastest to resolve them. It solved half or less of the complaints it received within two working days. 

The best energy firms resolve more than 80% of their complaints in the same time period.

In order for a company to be nearer the top of our table, its customers need to extremely satisfied with the service they're getting. 

Pros: It offers competitive electricity and gas tariffs

Cons: Comments indicate that it needs to address its digital tools

iSupplyEnergy electricity sources

iSupplyEnergy in the news

December: iSupplyEnergy overcharged around 4,400 customers on default tariffs energy regulator Ofgem announced.

The price of these tariffs is limited by a price cap but iSupply charged some homes too much between January and September 2019.

If you were overcharged, iSupplyEnergy should have refunded you. Overall it must pay £1.5m for its failings.

Ofgem said that senior employees knew about the breach but did not report it. It also found that iSupplyEnergy did not issue refunds in a ‘timely manner’. Ofgem found out thanks to a whistleblower.

April: iSupplyEnergy will pay £28,000 to customers as a result of breaching the prepayment meter price cap. Ofgem investigated after iSupply reported a system error which overcharged 2,039 customers and undercharged 5,500.

The error meant that prepayment keys didn't update some meters with the most recent rates.

If you were overcharged, iSupplyEnergy should have issued you a refund and compensation. If you were undercharged, you won’t have had to repay anything but your costs will have increased when you’re put on to the correct tariff.

March: iSupply increased the price of its variable energy tariff by 7%. This means that customers will have sees £76 on average added to their annual bill.
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