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Energy company reviews

iSupply Energy

By Sarah Ingrams

Article 17 of 33

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iSupply Energy

iSupplyEnergy has sold energy to domestic customers since 2012. iSupply 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, iSupply was bought by European gas and electricity giant Vattenfall in June 2017.

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

iSupply 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 joint 23rd place out of 30 energy companies rated by 7,429 members of the public in the annual Which? energy supplier satisfaction survey – the biggest of its kind. It shares 23rd position with Eon and EDF Energy

iSupply Energy's customer score of 57% is four percentage points below the average across all 30 companies in our survey (61%). Our top scorer was Octopus Energy, at 80%. Solarplicity was last, at 44%.

iSupplyEnergy score breakdown

The table below shows the breakdown of iSupply's score from our latest survey. Keep reading to find out more about what its customers think of it, and to compare iSupply's fuel mix to 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: this meant it received the highest rating of five stars out of five. Only 10 companies in the survey, including iSupply, got five stars in this category. 

Helping customers understand and reduce their energy use also received a better-than-average score of four stars. 

However, other categories did not do so well. 

Billing, both its accuracy and clarity, were given just a three-star rating. This isn't the worse score on the table but it isn't the best either. This is reflected in the rather mixed comments from existing customers. One respondent said that 'information is clearly displayed', while another explained that 'it's all done online and it isn't always easy to check.'

Its customer-service offering also seems 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. 

The energy supplier is an online-based company. Although its website is simple to use, iSupply doesn't offer any live-chat facilities. 

These comments also reflect iSupply Energy's published complaints data. Although it received a relatively low number of complaints overall in the first six months of last year, it also had one of the worst rates for resolution. Only 19% of complaints received were resolved within two working days. This was one of the worst rates of all the energy companies investigated. 

The best energy firms resolve close to 90% of their complaints in the same time period.

Not everyone is unhappy though; many customers feel like they are getting an OK service and don't have too many issues to comment on. 

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: Needs to address how it solves complaints

iSupplyEnergy electricity sources

iSupply in the news

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

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

If you were overcharged, iSupply Energy should have refunded you. Plus it must pay 1.5million for its failings.

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

April: iSupply Energy 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 have been overcharged, iSupply will refund and compensate you. If you have been undercharged, you won’t have to repay anything but your costs will increase when you’re put onto the correct tariff.

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

June: iSupply announced that it had been acquired by Vattenfall, the Swedish energy group. Vattenfall is one Europe's largest generators of renewable energy and it supplies more than seven million gas and electric customers in Northern Europe.

iSupply will continue to supply its more than 120,000 gas and electricity customers in the UK as an owned subsidiary of the energy company.

Fed up with high bills and slack customer service? Use Which? Switch to find the cheapest gas and electricity.