Niggling feelings of exclusion are significantly more likely than bullying to lead to job dissatisfaction, health problems and resignation.
"We've been taught that ignoring someone is socially preferable - if you don't have something nice to say, don't say anything at all," said Professor Sandra Robinson, who co-authored the study.
"But ostracism actually leads people to feel more helpless, like they're not worthy of any attention at all."
Robinson’s surveys found that people consistently rated workplace ostracism as both less inappropriate and harmful than harassment.
But studies of the actual results of ostracism conflicted with perceptions.
A statistical analysis of turnover amongst staff at a Canadian university also backed this up.
Those who had reported feeling isolated at work were significantly more likely to have quit three years down the track than those who had claimed to feel harassed.
"There is a tremendous effort underway to counter bullying in workplaces and schools, which is definitely important. But abuse is not always obvious," said Robinson.
"There are many people who feel quietly victimized in their daily lives, and most of our current strategies for dealing with workplace injustice don't give them a voice."
Silent ostracism may be more harmful than outright bullying when it comes to mental wellbeing at work, say researchers from the University of British Columbia’s Sauder School of Business.