To identify which factors are predictive of surgical site infection in upper extremity fractures, and to assess whether the timing of operative debridement influences infection risk.Retrospective database review.Hospitals participating in the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database.Patients in the NSQIP database with fractures involving the upper extremity.Surgical management of upper extremity fracture, including operative debridement for open injuries.Surgical site infection, including both superficial and deep infections.A total of 22,578 patients were identified, including 1,298 patients with open injuries (5.7% of total). The overall wound infection rate was 0.79%. Patients with open injuries were found to have a higher incidence of infection compared to those with closed injuries (1.7% vs 0.7%, p < 0.001). Independent risk factors for 30-day infection included open fracture diagnosis, obesity, smoking, and ASA class > 2 (all p < 0.05). Of patients with open fractures, 79.7% were taken expediently to the operating room. The rate of infection did not differ based on whether surgery was performed expediently or not (1.8% vs 1.1%, p = 0.431).Based on an analysis of the NSQIP database, the overall risk of surgical site infection following intervention for open or closed upper extremity fractures remains low. Risk factors for infection include open injury, obesity, and cigarette smoking. There was no difference in the infection rate based on the urgency of operative debridement.III.