While many consumers struggle with debt, some of them could be owed money by their energy providers.
A study by Go Compare has found 55 per cent of UK bill payers are actually in credit with their providers, due to overpaid bills.
The average amount owed back is £80, with 13 per cent due over £100, money that some may need badly as they battle to maintain credit repayments.
Moreover, only 22 per cent of those overcharged contacted their supplier to seek refunds, with 51 per cent taking no action and hoping the problem would solve itself over time.
Head of home services at the site Mark Greening said: "While direct debits are an efficient method of paying household bills, the way suppliers calculate bills can lead to customers paying more than they need to."
The news comes after a series of announcements of price hikes by leading energy firms in recent weeks.
EDF was the latest supplier to do this, announcing price rises of 10.8 per cent for both gas and electricity.
By James Francis