BACKGROUND The aim of this study was to prospectively duplicate previous retrospective findings showing that prestorage leukoreduction blunts the detrimental effect of aging on banked packed red blood cells transfused after injury. METHODS Over 19 months, trauma patients transfused with ≥4 U of packed red blood cells and surviving ≥24 hours were followed. The age of each unit was collected. RESULTS The cohort consisted of 153 patients. All models showed no association between advancing blood age and the likelihood of developing multiple-organ dysfunction syndrome or infections, regardless of whether the mean age of blood was analyzed as a continuous variable, as a percentage of blood received that was <14 days old, or as a dichotomized value >14 or <14 days old. CONCLUSIONS This prospective study duplicates previous retrospective findings of an abrogation of the detrimental effects of advancing mean packed red blood cell age on outcomes after trauma by performing prestorage leukoreduction.