Working over-65s up by a third
The number of people over the age of 65 who are in work has increased by a third in the past few years to more than a million, with older staff saying they enjoy working.
Most over-65s in work also benefit from social interaction with other age groups, said Saga.
Since May 2010, the number of workers aged 65 or more has risen from 800,000 to 1.068 million, an employment rate for the age group of 10%, the highest since comparable records began in 1992.
The employment rate for 50 to 64-year-olds has topped 68%, also a record, official data have shown.
Tim Pethick of Saga, which offers services to the over-50s, said: "Employment is not a zero-sum game, and while the number of over-50s in work is rising faster than the other age groups, the over-50s have not been squeezing young people out of the job market.
"The number of employed over-50s remains far lower than the number of employed 16 to 49-year-olds, and for older people, once they become unemployed, they find it much harder than other age groups to get back into work.
"Our research has shown that while some people have had to continue working longer than they might otherwise have planned, 88% have done so because they enjoy working and feel they benefit from the social interaction with other age groups."
Saga said the latest figures showed that 3.5% of all employed people in the UK were 65 or older, a 0.3% increase on a year ago.
Older people are more likely to get trapped in long-term unemployment than their younger colleagues if they lose their jobs, said the report.
Saga added that the number of workers over the age of 50 has been steadily rising, from just over eight million when the coalition Government was formed in 2010, to almost 8.9 million by October this year.
"The data suggests that businesses have turned to older workers, perhaps valuing their skills, experience and conscientious attitudes," said Saga.
But the report noted that many older people were postponing retirement because they needed to earn money, amid falling living standards.
The total number of people in work has topped 30 million for the first time on record.