The objectives were to examine clinical characteristics, length of recovery, and the prevalence of delayed physician-documented recovery, compare clinical outcomes among those with sport-related concussion (SRC) and non-sport-related concussion (nSRC), and identify risk factors for delayed recovery. Included patients (8-18 years) were assessed ≤14 days post-injury at a multidisciplinary concussion program and diagnosed with an acute SRC or nSRC. Physician-documented clinical recovery was defined as returning to pre-injury symptom status, attending full-time school without symptoms, completing Return-to-Sport strategy as needed, and normal physical examination. Delayed physician-documented recovery was defined as >28 days post-injury. Four hundred and fifteen patients were included (77.8% SRC). There was no difference in loss of consciousness (SRC: 9.9% vs nSRC: 13.0%, p = 0.39) or post-traumatic amnesia (SRC: 24.1% vs SRC: 31.5%, p = 0.15) at the time of injury or any differences in median Post-Concussion Symptom Scale scores (SRC: 20 vs nSRC: 23, p = 0.15) at initial assessment. Among those with complete clinical follow-up, the median physician-documented clinical recovery was 20 days (SRC: 19 vs nSRC: 23; p = 0.37). There was no difference in the proportion of patients who developed delayed physician-documented recovery (SRC: 27.7% vs nSRC: 36.1%; p = 0.19). Higher initial symptom score increased the risk of delayed physician-documented recovery (IRR: 1.39; 95% CI: 1.29, 1.49). Greater material deprivation and social deprivation were associated with an increased risk of delayed physician-documented recovery. Most pediatric concussion patients who undergo early medical assessment and complete follow-up appear to make a complete clinical recovery within 4 weeks, regardless of mechanism.