Introduction: This study aimed to examine difference in trauma injuries between bicycle users in winter months compared to summer months. Behavioral variables were also examined to assess seasonal variability, as well as associations with traumas. Methods: This was a retrospective cohort study of all bicycle related traumas presenting to a level I trauma center between the years 1998-2018. All data was collected through a standardized trauma database. Seasonal differences were examined by comparing trauma severity and behavior patterns between patients arriving in the months May-September (summer) and those arriving in November-March (winter). Outcome measures included: Injury Severity Scale, GCS, type of accident, helmet use, demographics and alcohol level. Groups were compared using t-tests and Chi-square analysis as appropriate. Results: A total of 980 bicycle related traumas were analyzed. There were a significantly greater number of injuries in the summer as compared to winter months (879 in summer vs. 101 in winter). While most injuries in both groups were rated in the severe range of the Injury Severity Scale, there were no differences in injury severity, initial GCS, deaths, or head injuries between the two seasons. There were also no differences in drug, alcohol, or helmet use. The only significant difference between seasons was that winter riders were more likely to be male. Overall, helmet use was associated with lower injury severity, less head trauma, and a higher initial GCS. Use of alcohol was associated with less likelihood of wearing a helmet. Conclusion: In conclusion, bicycle use in winter does not appear to be associated with worse outcomes than summer. Public health interventions can continue to encourage winter bicycle use, with the encouragement of helmet use and avoidance of alcohol when cycling as an important protective factor in both seasons.