One of the Big Six energy suppliers has said it writes off four times as much "bad debt" every year as the funds it retains from closed customer accounts.
A statement from SSE said it takes "all reasonable steps" to return money to customers and always views "any credit as theirs", adding:
No matter how much time passes, if they come forward and we can identify an outstanding credit, we will return it to them.
We're happy to work with anyone who has legitimate suggestions for how we can find customers more easily and efficiently.
However, the reality is that the bad debt we have had to write off in recent years is about four times the amount of credit that couldn't be returned, so this is not a situation that benefits us.
More top news
On English votes for English laws Ed Miliband is damned if he does and damned if he doesn't.
School fees, pricey private medical care and the fear of interest rate rises mean even those on £200,000 are feeling the pinch.
Overnight it will be cooler and fresher but most places will stay dry with a nippy start to Sunday.