The number of people working on after they qualify for state pension has nearly doubled to 1.4 million over the last 18 years.
According to the Office for National Statistics, women are most likely to stay in work, usually in a part-time job.
12 per cent of older people now choose to work on, beyond 65 for men and for women beyond 61 as the female pension age starts to move up in line with men.
Often it's because of pressure to top up the state pension, but many simply choose to stay active and earning.
A large number are part-time or self-employed, though the share in full time work could grow now that employers have been forced to scrap compulsory retirement ages.
Women make up nearly two thirds of those working on, most frequently as cleaners, administration assistants, care workers and in shops.
Jobs topping their list for men are farming and driving taxis.