Of the expected £85bn of debt in 2018, secured debt such as mortgages account for some £73bn of the total.

According to the Centre for Economics and Business Research (CEBR), nearly 40% of 65-74-year-olds with an interest-only mortgage will struggle when the capital repayment is due.

However, secured debt is not the only burden of retirees.

The Key Retirement study found that 26%, or just over one in five of over-70s are using three or more credit cards to support their living costs – with one in 10 holding outstanding balances for more than a year.

The study also showed that one in seven of over-65s rely on credit cards to supplement their retirement income.

Yet, post retirement debt was not fuelled by over-spending.

Rather, it was a combination of inadequate saving, the launch of pension freedoms, and unexpected bills which meant pensioners needed to rely on borrowing in retirement.

‘Debt is a silent source of worry’

The survey used a sample of 3,000 adults aged 55 and over, split between those aged 55 to 65 still in work, retirees aged 65 to 70, and retirees above 70.

Over half of those surveyed (55%) said they had to use credit cards to pay for unexpected bills, with car repairs being the most common issues followed by emergency house repairs.

“A comfortable stress-free retirement is what we all want but debt is increasingly a silent source of worry for too many retirees,” said Alvin hall, independent financial expert.

Dean Mirfin, chief product officer at Key Retirement, added: “The issue of debt in retirement isn’t discussed as openly as it should be.

“However, not only is it a problem, it’s a growing one.

“Pensioners worried about debt are not alone. We are all living longer and that means our savings have to last longer and we have to plan more carefully. Helping out family can also rapidly cut retirement funds while pension freedoms make it easier to access cash.”