Importance: Best practices for antibiotic use after facial plastic and reconstructive procedures have been the subject of much debate, and there is a need for large-scale data to guide further development of evidence-based guidelines for antibiotic use in this setting. Objective: To assess patterns of postoperative antibiotic prescriptions and infection rates after nasal and oculoplastic procedures. Design, Setting, and Participants: A retrospective population-based cohort study was conducted using IBM MarketScan Commercial and Medicare Supplemental research databases of 294039 patients who underwent facial plastic surgery procedures between January 1, 2007, and December 31, 2015. Patients were excluded if they were younger than 18 years, lacked continuous insurance coverage for 1 year before and after the procedure, or underwent additional procedures on the surgery date of interest. Statistical analysis was performed from January 1, 2007, to December 31, 2016. Main Outcomes and Measures: Primary outcomes were antibiotic prescription patterns in the immediate postoperative period and rates of postoperative infectious complications. Explanatory variables included patient demographics, procedure type, and relevant comorbidities, which were used in multivariable logistic regression analysis. Results: Of the 294039 patients who met inclusion criteria (55.9% women and 44.1% men; mean [SD] age, 54.0 [18.6 years]), 45.2% filled prescriptions for postoperative antibiotics, including 55.3% of patients undergoing nasal procedures and 14.7% of patients undergoing oculoplastic procedures. Superficial surgical site infections occurred in 1.6% of patients, while deep surgical site infections occurred in 0.3% of patients. On multivariable logistic regression, patients receiving postoperative antibiotics were at significantly decreased risk of postoperative infections (nasal procedures: adjusted odds ratio [aOR], 0.144 [95% CI, 0.102-0.203]; oculoplastic procedures: aOR, 0.254 [95% CI, 0.104-0.622]) compared with those who did not receive postoperative antibiotics. Increased duration of postoperative antibiotics was not associated with reduced rates of infectious complications (nasal procedures: aOR, 1.000 [95% CI, 0.978-1.022]; oculoplastic procedures: aOR, 1.024 [95% CI, 0.959-01.092]). Despite being more likely to experience postoperative infections, patients with a history of tobacco use (aOR, 0.806 [95% CI, 0.747-0.870]), immunodeficiency (aOR, 0.774 [95% CI, 0.737-0.813]), or type 1 or 2 diabetes (aOR, 0.810 [95% CI, 0.772-0.850]) were less likely to be prescribed antibiotics than those without these conditions. Conclusions and Relevance: Postoperative antibiotic prescriptions were associated with reduced rates of infections after facial plastic surgery. This study highlights the role of population-level data in the development of best practices for postoperative antibiotic use and identifies the need for additional examination of antibiotic use patterns and recommendations for populations at increased risk for postoperative wound infection.