Objective Proper use of automobile seat belt in a motor vehicle crash is associated with reduced morbidity and mortality, shorter hospital stays, reduced resource utilization, and fewer missed work days. Seatbelt compliance nationwide is 86%. This study was undertaken to identify factors associated with noncompliance with seatbelt use among admitted patients following a motor vehicle crash. Results Among 766 participants, the overall rate of seatbelt noncompliance was 32% (N = 245). Some participants met the legal limit of intoxication (80 mg/dl) (N = 119 patients; 22%). Drug use was high among this population, including THC (30%), opiates (29%), benzodiazepines (24%), cocaine (10%), and methamphetamine (10%). Patients who did not wear seat belts were more likely to be male (62.4% no seat belt vs. 51.8% seat belt), intoxicated (30.5% vs. 17.0%), screen positive for cocaine (18.2% vs. 4.7%), THC (37.7% vs. 24.2%), and methamphetamine (15.6% vs. 5.9%). We did not detect significant differences by seat belt use with respect to ethnicity, mode of arrival, day of week, opiate use, or benzodiazepine use. Conclusions In this study, 32% of patients in motor vehicle crashes were not compliant with seat belt use. Noncompliance with seat belt use was higher among patients who were male, younger age, intoxicated, or who had positive screens for cocaine, THC, or methamphetamine.