Purpose Bariatric surgery is recognized as the treatment of choice for class III obesity (body mass index ≥40) and has been increasingly recommended for obese patients. Prior research has suggested an excess of deaths due to suicide following bariatric surgery, but few large long-term follow-up studies exist. We examined postbariatric surgery suicides by time since operation, sex, age, and suicide death rates as compared with US suicide rates. Methods Medical data following bariatric operations performed on Pennsylvania residents between January 1, 1995 and December 31, 2004 were obtained from the Pennsylvania Health Care Cost and Containment Council. Matching mortality data from suicides between September 1, 1996 and December 28, 2006 were obtained from the Division of Vital Records, Pennsylvania State Department of Health. Results There were 31 suicides (16,683 operations), for an overall rate of 6.6/10,000; 13.7 per 10,000 among men and 5.2 per 10,000 among women. About 30% of suicides occurred within the first 2 years following surgery, with almost 70% occurring within 3 years. For every age category except the youngest, suicide rates were higher among men than women. Age- and sex-matched suicide rates in the US population (ages 35-64 years) were 2.4/10,000 (men) and 0.7/10,000 (women). Conclusions Compared with age and sex-matched suicide rates in the US, there was a substantial excess of suicides among all patients who had bariatric surgery in Pennsylvania during a 10-year period. These data document a need to develop more comprehensive longer-term surveillance and follow-up methods in order to evaluate factors associated with postbariatric surgery suicide.