Exposure to the suicide of another is common, but the magnitude and effects of such exposure are not well quantified. From a national random telephone survey of U.S. adults, we estimated the 12-month incidence of exposure to suicide and its association with suicidal ideation, planning, and behavior. Of 5,238 respondents, 342 (a weighted 7.0% representing 13.2 million persons) reported knowing a suicide decedent from the previous year. Univariate analysis showed persons reporting such exposure were significantly more likely to describe suicidal ideation and behavior than those unexposed; multivariate analysis showed no association. Though the risk related to suicide exposure may be small, given the magnitude of exposure, it may warrant intervention efforts because of its potential societal impact.