Stevie C.Y. Yap, Ivana Anusic and Richard Lucas of Michigan State University studied the data of thousands of participants in a long-running, national British survey.
They set out to find whether personality helps people adapt to major life events including marriage.
The researchers found personality traits such as conscientiousness or neuroticism did not help people deal with losing a job or having a baby.
"Past research has suggested that personality is important in how people react to important life events," Yap said in a statement. "But we found that there were no consistent effects of personality in how people react and adapt to these major events."
They also found in general, similar-aged participants who did not get married showed a gradual decline in happiness as the years passed, but those who were married largely bucked this trend.
The study was published online in the Journal of Research in Personality.