PURPOSE: Little is known about opioid use after bariatric surgery among patients who did not use opioids chronically before surgery. Our purpose was to determine opioid use the year after bariatric surgery among patients who did not use opioids chronically pre-surgery and to identify pre-surgery characteristics associated with chronic opioid use after surgery. METHODS: This retrospective cohort study across nine US health systems included 10 643 patients aged 21 years or older who underwent bariatric surgery and who were not chronic opioid users pre-surgery. The main outcome was chronic opioid use the post-surgery year (excluding 30 post-operative days) defined as >/=10 dispensings over >/=90 days or >/=120 total days' supply. RESULTS: Overall, 4.0% (n = 421) of patients became chronic opioid users the post-surgery year. Pre-surgery opioid total days' supply was strongly associated with chronic use post-surgery (1-29 days adjusted odds ratio [OR] 1.89 [95%CI, 1.24-2.88]; 90-119 days OR, 14.29 [95%CI, 6.94-29.42] compared with no days). Other factors associated with increased likelihood of post-surgery chronic use included pre-surgery use of non-narcotic analgesics (OR, 2.22 [95%CI, 1.39-3.54]), antianxiety agents (OR, 1.67 [95%CI, 1.12-2.50]), and tobacco (OR, 1.44 [95%CI, 1.03-2.02]). Older age (OR, 0.84 [95%CI, 0.73-0.97] each decade) and a laparoscopic band procedure (OR, 0.42 [95%CI, 0.25-0.70] vs. laparoscopic bypass) were associated with decreased likelihood of chronic opioid use post-surgery. CONCLUSIONS: Most patients who became chronic opioid users the year after bariatric surgery used opioids intermittently before surgery.