According to the charity, it gave debt advice to 1.4 million people in the two countries in 2005-06, an increase of 11 per cent on the year before.
Citizens Advice chief executive David Harker was concerned about the findings: “Our debt enquiry figures are deeply worrying.
“They suggest that a growing number of people are getting deeper into unmanageable debt it will be difficult to recover from.”
His comments come as the government reports that insolvencies rose sharply this year as more people struggle with debt and take out an Individual Voluntary Arrangement (IVA) or become bankrupt.
Mr Harker said that there needs to be more people able to give debt advice to allow intervention before repayments become too much of a problem.
He also called for more responsible lending from credit providers to help people avoid taking on debt they cannot afford.