Importance: The predictors of postoperative complications after paramedian forehead flaps (PMFF) are unknown. Objective: To determine whether preoperative factors can predict post-PMFF complications. Design, Setting, Participants: A retrospective review of 1438 adults from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database who underwent PMFF between 2010 and 2018. Main Outcomes and Measures: Surgical complications, medical complications, and all-cause mortality. Results: Of the 1438 patients, 75 experienced postoperative complications (5.2%). Of these, 36 developed isolated surgical complications (2.5%), 29 developed isolated medical complications (2.0%), and 8 developed concurrent surgical and medical complications (0.5%). Of the three mortalities (0.2%), one patient developed concurrent surgical and medical complications. A dirty or infected wound classification was the strongest predictor of postoperative complications (odds ratio [OR] 13.5; confidence interval [95% CI] 3.4-49.5). In contrast, the likelihood of postoperative complications decreased significantly with outpatient procedures (OR 0.4; 95% CI 0.2-0.8). Conclusions and Relevance: A dirty or infected wound classification is the strongest predictor of postoperative complications after PMFF.