Workers are switching careers after being made redundant, want to earn more money, or are bored in their job, new research shows.
A study by the Co-op found that more than half of people over the age of 50 have had at least three different jobs.
The survey of 1,200 adults revealed that being made redundant was the main reason for finding a new profession, although one in seven said they were bored and a similar number wanted to do something more interesting.
The average expected age for retiring was 64, according to the report.
Jenny Atkinson, of the Co-op, said re-training for a different career was a good way to keep minds active.
Work and Pensions Secretary Damian Green said: "Staying in work for longer can have a hugely positive impact on people's lives, not only by boosting their savings but also preserving their physical and mental health.
"Today I'm launching a Fuller Working Lives strategy to help increase the opportunities for older people to remain in work. For many that could be taking up a new career entirely."