Low levels of serum vitamin D have been linked to numerous musculoskeletal and nonmusculoskeletal conditions. Vitamin D deficiency appears relatively high among various patient subpopulations, including patients with fracture nonunion. We conducted a retrospective study to determine the prevalence of vitamin D deficiency and insufficiency in a large population of patients with orthopedic trauma. The study included all patients who were over age 18 years, had no risk factors for vitamin D deficiency, and were treated for an acute fracture at a Level 1 trauma center. Between January 2009 and September 2010, 889 trauma patients had recorded serum 25-hydroxyvitamin D levels. Overall prevalence of combined vitamin D deficiency/insufficiency was 77%; prevalence of vitamin D deficiency alone was 39%. There were no statistically significant (P < .05) age or sex differences among the population. There did not appear to be a seasonal difference. Vitamin D deficiency and insufficiency in acute orthopedic trauma patients appear very common. Further investigation is needed to fully understand the clinical significance.