Background Trauma centers are designated to provide systematized multidisciplinary care to injured patients. Effective trauma systems reduce patient mortality by facilitating the treatment of injured patients at appropriately resourced hospitals. Several U.S. studies report reduced mortality among patients admitted directly to a level I trauma center compared with those admitted to hospitals with less resources. It has yet to be shown whether there is an outcome benefit associated with the ''level of hospital'' initially treating severely injured trauma patients in Australia. This study was designed to determine whether the level of trauma center providing treatment impacts mortality and/or hospital length of stay. Methods Outcomes were evaluated for severely injured trauma patients with an Injury Severity Score (ISS)[15 using NSW Institute of Trauma and Injury Management data from 2002-2007 for our regional health service. To assess the association between trauma centers and binary outcomes, a logistic regression model was used. To assess the association between trauma centers and continuous outcomes, a multivariable linear regression model was used. Sex, age, and ISS were included as covariates in all models. Results There were 1,986 trauma presentations during the 6-year period. Patients presenting to a level III trauma center had a significantly higher risk of death than those presenting to the level I center, regardless of age, sex, ISS, or prehospital time. Peer review of deaths at the level III center identified problems in care delivery in 15 cases associated with technical errors, delay in decision making, or errors of judgement. Conclusion Severely injured patients treated at a level III center had a higher mortality rate than those treated at a level I center. Most problems identified occurred in the emergency department and were related to delays in care provision. This research highlights the importance of efficient prehospital, in-hospital, and regional trauma systems, performance monitoring, peer review, and adherence to protocols and guidelines.