The Ipsos-Reid survey of people aged 50 or more found 62 per cent of the retired respondents had chosen the time when they left the workforce.
The poll also found 20 per cent of retired respondents had only a month's warning or less, while 42 per cent had less than six months notice before they retired.
By contrast, 85 per cent of the working boomers said they expected to have a choice about the timing of their retirement.
Health was cited as the main reason for the timing of retirement, ahead of having enough money or being unhappy at work.
The poll was limited to people with household assets of at least $100,000 and conducted by Ipsos Reid for RBC Royal Bank from Feb. 24 to March 12.
Note to readers: This is a corrected story. An earlier version said nearly 30 per cent of retired respondents said they didn't have a choice about their retirement date.
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