Background: Although new persistent opioid use and high-risk prescribing have been recognized as important postoperative complications among younger patients (18–64 years of age), little is known about the incidence for postoperative opioid use among older patients (>65 years of age). Methods: We analyzed a 20% national sample of Medicare Part D claims among beneficiaries >65 years of age who underwent a major or minor surgical procedure between January 1, 2009, and June 30, 2015. We identified patients without an opioid prescription fill in the year before surgery and examined their perioperative and 6-month postoperative opioid prescription fills to examine the incidence of new persistent opioid use and high-risk prescribing. Results: We identified 81,839 opioid naïve patients who underwent surgery and filled an opioid prescription perioperatively. Overall, 9.8% developed new persistent opioid use. Risk factors for new persistent opioid use included major surgery (adjusted odds ratio [aOR] 1.24, 95% confidence interval [CI] 1.17–1.31), more comorbid conditions (aOR 1.71, 95% CI 1.58–1.84), mood disorders (aOR 1.16, 95% CI 1.09–1.24), suicide or self-harm (aOR 1.60, 95% CI 1.05–2.44), substance abuse disorders (aOR 1.38, 95% CI 1.20–1.59), filling an opioid prescription before surgery (aOR 1.67, 95% CI 1.58–1.77), higher amounts of opioids filled (aOR 1.44, 95% CI 1.37–1.52), black race (aOR 1.23, 95% CI 1.12–1.36), and Medicaid eligibility (aOR 1.45, 95% CI 1.35–1.55). Conclusion: About 10% of Medicare beneficiaries who were previously opioid naïve continue to fill opioids past 3 months after surgery. In addition to comorbidities and mental health conditions, new persistent opioid use is associated with surgery type, preoperative opioid fill, high-risk prescribing practices, and sociodemographic factors.