Two out of three people believe they will have to work past 65, mainly because they do not expect to have enough money to retire, research finds.
According to a study by Portus Consulting, more than one in ten (11%) expect to work beyond 76 while one in 20 says they will never stop working.
Almost three quarters (74%) of those who expect to stay in work fear they will not be able to afford to retire, while 13% expect to still be supporting their children financially.
The research shows that half of people over 65 and currently working are doing so because they do not have enough money to live on.
Just two out of five surveyed believed they would have adequate income in retirement.
On a more positive note, 26% of those who expect to work beyond 65 say they would do so because they enjoy working, and don't want to become bored if they retire.
Steve Watson, commercial director at Portus Consulting said the demographics of the UK workforce were changing, which had implications for employers in terms of the range of benefits they offered.
He said: "An older workforce will want greater access to advice or guidance on how to use their pension savings while still at work, and it can also have huge implications for the provision of medical and critical insurance cover."