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By Sarah Ingrams

Article 17 of 31

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Small energy firm Iresa paid its customers interest on any credit balance built up. Iresa has now ceased trading. Find out more about the firm in our Iresa review.

Iresa, a relatively new independent gas and electric supplier, claimed its focus and aim was price and quality of service.  

But on the 27 July, Iresa ceased trading. On 1 August, energy regulator Ofgem announced that Octopus Energy would take on Iresa's 90,000 customers. Iresa customers' credit will be protected and their gas and electricity supply will not be affected. Ofgem told customers to take a meter reading, not to switch, and to wait until the Octopus Energy contacted them by 14 August.

Back on the 27 June 2018, industry regulator Ofgem extended a ban on Iresa accepting new energy customers indefinitely. It first imposed the ban in March, and in May 2018, Ofgem said Iresa ‘has not taken adequate steps to meet the requirements’. In June Ofgem said the ban would continue for the 'foreseeable future' until Iresa's customer service shows 'significant improvement'. Ultimately, Iresa risked losing its licence to supply gas and electricity if it does not improve.

At the time, we advised prospective Iresa customers to give it a miss. 

About Iresa

Iresa began trading in 2016, due - it says - to recognising a need to cut down on operational costs and pass these savings on to its customers. Iresa wants to targets low-energy users. 

It had two tariffs available and both at a very competitively price. Iresa also paid an interest of 4.5% on any balance built up. 

Iresa is based in Nottingham and grew its customer base quickly since launching. This is the first year we have included Iresa in our annual satisfaction survey.

You can find out how Iresa's prices compare with your current deal - use Which? Switch to find the cheapest gas and electricity.

Iresa customer score

Iresa came 16th out of 31 energy firms rated by 8,761 customers in our annual Which? energy company satisfaction survey.

'The account is easy to set up.'

Iresa customer

Its customer score of 64% was nine percentage points above the average for British Energy companies. It beat all of the Big Six firms, but sat just within the bottom half of our table.

Iresa customer score breakdown

Below we show the breakdown of Iresa’s score from our latest survey. Scroll down to find out more about what it was like to be an Iresa customer, and to see what actually goes into its fuel mix.

Find out how Iresa compares with other energy companiesclick to see the full results of the best and worst energy companies.

Which? verdict on Iresa

In our customer survey results, carried out before Ofgem banned it from taking on new customers and it went bust, it finished just below the middle of our table, in sixteenth position. Iresa received very mixed reviews from its customers.

The Nottingham-based business launched in 2016 with the goal of reducing energy bills, especially for low-energy users. Iresa said it had created its own technology to run the business in order to offer these cheaper deals.

There were two tariffs available and both were very competitive. You could opt for electricity only and dual fuel, but there was no gas-only option.

In 2017, Iresa's Flex4 12 month fixed tariff was one of the cheapest dual fuel deals on the market at £834. There was no exit fee charged if you wanted to leave this fixed tariff.

Iresa also paid interest on any credit balance built up, at a rate of 4.5%. This, plus offering a cheap tariff, helps explain why customers rated Iresa five stars out of five for value for money.

'Iresa pays a good monthly rate of interest on credit balances.'

Iresa customer
Iresa also scored highly for its billing accuracy - with four stars out of five. You can manage your account online.

'Iresa seems to be very efficient. It sends emails each month for requesting readings, saying the bill is ready to view and advising the date that monthly payment will be requested from my bank. All a week before it is due.'

Iresa customer

Iresa was not part of the Warm Home Discount. Unlike larger firms, it's not compulsory for smaller firms to offer the scheme, which provides a one-off payment to those struggling to pay their energy bills. Although some small firms do offer it, such as Bristol Energy.  

If you want to switch, it takes around 30-35 days but payment will come out beforehand – typically around two weeks after choosing your tariff.

Customer service

Iresa only scored three stars out of five in our survey for online customer service. We didn't receive enough survey responses to give Iresa's phone service a star rating. However, bad customer service was repeatedly commented on by respondents in our survey. 

One Iresa customer told us: ‘It takes you over an hour to get to the top of the telephone queue, then sometimes you get cut off. If you email them it can take several months for them to reply.’ While another said: ‘They take a long time to respond, if at all.’

'Try emailing them or messaging from their website. They don't respond until it is too late to do anything.'

Iresa customer

This reflected the news that Iresa stopped taking on new customers on two occasions in the last two years, after energy regulator found that customers were struggling to get hold of Iresa. It was under investigation by the regulator and banned from taking on new customers indefinitely from June 2018. Then in late July, it went bust. 

Pros: Very competitive prices and interest on accounts in credit.

Cons: Customers are not happy with customer service. 

Iresa electricity sources

As Iresa was a new supplier it had not disclosed its fuel mix.

Iresa in the news


August: Octopus Energy will take on all of Iresa's 90,000 customers, Ofgem announced. It'll honour customers' credit balances, contact them by 14 August, and complete the switchover by 21 August. In the mean time customers should take a meter reading and wait until they are contacted.

July: Iresa ceased trading on the 27 July. Ofgem reassured Iresa customers their credit and supply would be protected.

June: The ban on Iresa taking on new customers was extended ‘indefinitely’ by Ofgem. The regulator said Iresa had reduced call waiting times and shown signs of improvement in complaints handling and how it handles vulnerable customers. But it has not made enough progress on its customer email backlog. The ban will remain in place until Ofgem ‘sees a significant improvement’.

May: Ofgem said that Iresa ‘has not taken adequate steps to meet the requirements’ of its order in March which demanded improvement in phone and email response times, addressing customers’ concerns and recognising customers in vulnerable situations in order to help them. Iresa is still forbidden from taking on new customers before 27 June 2018.

March: Iresa was banned from taking on new customers until it resolves customer service issues. Energy regulator Ofgem also forbade Iresa from increasing customers' direct debits or asking for one-off payments. Iresa must make improvements over the next three months. If it fails, it ultimately risks losing its license to sell gas and electricity. Find out what Iresa must do to improve.

February: Energy regulator Ofgem begun investigating Iresa’s customer service. It opened the probe shortly after Which? reported that Iresa customers faced big unexpected payments.

Ofgem will look into whether Iresa broke rules including about treating customers fairly on the phone and when handling complaints, giving customers in debt enough notice that a repayment was being taken, establishing that customers in debt were able to pay, letting customers switch supplier, and rules around refunding customers promptly.


April: Iresa shut its doors to new customers after Ofgem became aware that current customers were struggling to get in contact with the supplier when they had any queries or complaints. Ofgem informed Iresa they would need to resolve the problem and explain how it would be easy for customers to contact them in the future.

Iresa has now reopened its doors to new customers.

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