More than 40 per cent of homeowners over 65 years old have interest-only mortgages, according to research from More 2 Life.
The lender says 41 per cent of the age group have such a loan. Within that, nearly 40 per cent are 65-74 years old and the remainder are over 75.
More 2 Life also says the growth in average unsecured debt levels for over 75s was higher than for any other age group.
For the 75-84 age group, average unsecured debt rose 201 per cent from £162 in 2006-2008 to £487 in 2012-2014.
For the over-85 age group, debt levels rose 218 per cent from £36 to £115 over the same time periods.
More 2 Life managing director Dave Harris says: “This new research shows that the number of interest-only mortgages among older homeowners will continue to be an issue as these begin to mature in the next decade.
“Demand for alternative later life lending on this scale has the potential to double the equity release market this year alone.
“For many of these individuals without an alternative capital repayment strategy, retirement lending and in particular lifetime mortgages will be the solution to their finances.”