Objective: Previous studies looking at emergency department (ED) crowding and delays of care on outcome measures for certain medical and surgical patients excluded trauma patients. The objectives of this study were to assess the relationship of trauma patients’ ED length of stay (EDLOS) on hospital length of stay (HLOS) and on mortality; and to examine the association of ED and hospital capacity on EDLOS.Methods: This was a retrospective database review of Level 1 and 2 trauma patients at a single site Level 1 Trauma Center in the Midwest over a one year period. Out of a sample of 1,492, there were 1,207 patients in the analysis after exclusions. The main outcome was the difference in hospital mortality by EDLOS group (short was less than 4 hours vs. long, greater than 4 hours). HLOS was compared by EDLOS group, stratified by Trauma Injury Severity Score (TRISS) category (< 0.5, 0.51-0.89, > 0.9) to describe the association between ED and hospital capacity on EDLOS.Results: There was no significant difference in mortality by EDLOS (4.8% short and 4% long, p = .5). There was no significant difference in HLOS between EDLOS, when adjusted for TRISS. ED census did not affect EDLOS (p = .59), however; EDLOS was longer when the percentage of staffed hospital beds available was lower (p < .001).Conclusions: While hospital overcrowding did increase EDLOS, there was no association between EDLOS and mortality or HLOS in leveled trauma patients at this institution.