Objective: The purpose of this study was to examine 3-month neuropsychological outcomes following mTBI (GCS 13–15) in participants with and without positive CT scans. Method: 321 participants with mTBI (GCS score >12) from the prospective multicenter Transforming Research and Clinical Knowledge (TRACK-TBI) study were included in the current analyses, 44% of whom had positive CT scans acquired at the Emergency Department. Participants received a 3-month follow up assessment on neuropsychological measures including Trail Making Test (TMT), WAIS-IV Processing Speed (PSI) Index, and California Verbal Learning Test (CVLT). Psychiatric and TBI history, and post-concussion symptoms (Rivermead Post-Concussion Symptoms Questionnaire–RPQ) were also obtained. Results: Using ANOVA, the CT+ group demonstrated significantly lower PSI scores (F = 4.46, p < .01), CVLT Total Learning Trials 1–5 (F = 28.04, p < .001), CVLT Short Delay Free Recall (F = 21.26, p < .01), and CVLT Long Delay Free Recall (F = 26.62, p < .01) scores compared to the CT- group. Differences remained after controlling for age, psychiatric history and prior TBI. Conclusion(s): Individuals with mTBI are often conceptualized homogeneously with respect to severity and recovery. However, results demonstrate variability within this group at 3-months post-injury. Those who were CT+ had poorer neurocognitive performance relative to those who were CT-, even after accounting for demographic and pre-injury factors. This underscores the heterogeneity within individuals with mTBI and highlights the importance of serial follow-up including neurocognitive measures.