Citizens Advice figures show that 770,000 Britons missed repayments as they failed to properly manage their debt.
“We are very concerned about the numbers of people who are missing payments,” said Citizens Advice chief executive David Harker.
“Missing payments on mortgages or secured loans could lead to arrears and possibly repossession.”
Last month financial experts from Moneyfacts.co.uk and the Post Office expressed concern at the risks people are taking with repayments and repossession.
Younger people were deemed to be most at risk of repossession in the new report, with an eighth of 21 to 24-year-olds missing at least one repayment in the past year.
Citizens Advice give debt advice on how to budget and Mr Harker said that there is a “clear need” for more people to be aware of the risks of taking on financial commitments.