Almost a quarter (22%) of 55 to 64-year-olds have no private pension savings, figures from the Office for National Statistics (ONS) show.
The problem is particularly acute among women aged 55-64 who have not started claiming state pension benefits, with 40% lacking private pension wealth.
The issue was revealed by an analysis of ONS data by Just Group, whose group communications director, Stephen Lowe, said:
"This generation will be retiring over the next 10 years and many hundreds of thousands will be reliant on the State Pension and other benefits.
"While the maximum new State Pension is £168.60 a week, for those who have built up their full entitlement, organisations such as the Joseph Rowntree Foundation put the minimum weekly income required by a single pensioner higher at about £200 and £310 for a couple.
"Even assuming people retiring will get the full State Pension - and only about 44% currently do qualify for the full amount - that is still a significant gap between income and expenditure."
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