Four out of 10 people aged over 65 are continuing to work in order to boost their income, a survey suggests.
Around 40% of people who have reached the state pension age are continuing to work full-time or part-time, with the average person not expecting to fully retire for at least another five years.
A fifth of those who have continued to work beyond the age of 65 claim they will never retire completely, according to retirement planning group Heartwood.
Nearly a third of pensioners who have continued working said they had delayed their retirement for longer than they had originally planned.
Around 32% said they had decided to stay in work because of falls in the value of their pension, while 27% blamed the higher cost of living for their decision.
But one in four of those questioned said they needed to continue working because they were still supporting their children financially, while 8% were worried about the rising cost of medical care.
Simon Lough, chief executive of Heartwood, said: "While the Government has chosen to position ending the default retirement age as a victory for older people against age discrimination, the sad truth for many is that they're not working through choice but because they can't afford to stop."
ICM questioned 450 people aged 65 and over during July.