Energy firm iSupply to pay £1.5m after overcharging customers

The cap came into force on 1 January this year and sets maximum rates that suppliers are allowed to charge their default-tariff customers.

But from January to March, iSupply overcharged 4,400 customers £36,270 in total. And from April to September, 25 customers were collectively overcharged by £53.

Energy regulator Ofgem says senior iSupply staff were aware of the rule breach in January but didn't report it, with a whistleblower later coming forward.

Ofgem says it has decided not to take formal enforcement action after iSupply took steps to address its failings and the fact it will pay £1.5 million into the regulator's 'voluntary redress fund', a kitty that goes towards charities, trusts and third-party organisations that help energy consumers.

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What does Ofgem say?

Ofgem's director of conduct and enforcement Anthony Pygram said: "If a licensee breaches the rules, it quickly needs to tell Ofgem and put things right for its consumers. However, iSupply has admitted it failed to do so in this instance."

He added: "The action we have taken against iSupply sends a strong message that all suppliers must treat their customers fairly, and quickly address known harm so that customers are protected, or face the consequences."

What does iSupply say?

Monica Collings, co-chief executive of iSupply, said: "Our expectation is that we will always provide a high-quality service to all customers. Naturally, I feel very disappointed that earlier this year we didn't manage to do that.

"We have apologised to affected customers and made amends where they were negatively impacted. We have also worked very hard to improve our capabilities, hugely reinforcing our compliance resource and expertise to ensure this or similar issues can't be repeated."