'Don't ask, don't get': Big Six energy companies in campaign to reunite former customers with their cash

Energy companies operate on a "don't ask, don't get" basis for those in credit, said Martin Lewis, founder of MoneySavingExpert, so the campaign is welcome news. "In a perfect world energy companies would be proactively writing to every customer address they have where people are owed credit and paying out automatically," said Mr Lewis. "I don’t hold out too much hope for that, but this is at least a step in the right direction."

If a deceased relative was an account holder, then the beneficiary will need to demonstrate their entitlement to any proceeds of their estate if pursuing their closed account.

"Inevitably, there will be some former customers who will not be found and so the major suppliers are announcing what will happen to credit balances from now on. In future, after two years, the credit balance will be used to help vulnerable customers – and suppliers will make it very clear what is happening," Ms Knight said.

The unclaimed credit would amount to at least £65m over five years, she added.

Energy minister Amber Rudd said: "People should rightly be returned money that is theirs and was left behind when they moved house or switched.

"Earlier this year, the Government and Ofgem announced plans to get to the bottom of problems with outstanding credit balances and an agreement was reached with the major energy companies to ensure they automatically refund direct debits to customers who are in credit."

Ofgem said that any failures to deliver on the initiatives announced in today's campaign could trigger further action by the regulator, including enforcement.

In February, Ofgem called on suppliers to tackle three key issues: reuniting individual consumers with their money, using balances that cannot be returned to individuals in a way that would benefit consumers more widely and preventing this issue from happening again.

The Telegraph launched its own Energy Shambles Watch campaign in July to pressure the energy industry into improving its appalling customer service levels. We asked our readers to tell us of their bad experiences. If you have a story to tell, email us at money@telegraph.co.uk.

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