Objectives: This prospective cohort study aimed to investigate whether there are differences in health outcomes among persons with mild or moderate injuries who were hospitalised compared with those not hospitalised following a road traffic crash. Setting: Sydney Metropolitan, New South Wales, Australia. Participants: Persons aged ≥18 years involved in a motor vehicle crash were surveyed at baseline (n=364), and at 12 (n=284) and 24 months (n=252). A telephone-administered questionnaire obtained information on a range of socioeconomic, and preinjury and postinjury psychological and heath characteristics of all participants. Primary outcome measure: Participants who reported admission to hospital for 24 h or more (but less than 7 days) after the crash were classified as being hospitalised; those admitted for less than 24 h were classified as non-hospitalised. Results: Around 1 in 5 participants (19.0%) were hospitalised for ≥24 h after the crash. After adjusting for age and sex, hospitalised participants compared with those not hospitalised had approximately 2.6 units (p=0.01) lower Short Form-12 Physical Component Summary (SF-12 PCS) scores (poorer physical well-being) and approximately 4.9 units lower European Quality of Life visual analogue scale (EQ-VAS) scores (p=0.05), 12 months later. After further adjusting for education level, whiplash, fracture and injury severity score, participants who were hospitalised had approximately 3.3 units lower SF-12 PCS (p=0.04), 12 months later. The association with EQ-VAS did not persist after multivariable adjustment. No significant differences were observed between the 2 groups in health outcomes at 24-month follow-up. Conclusions: These findings indicate that long-term health status is unlikely to be influenced by hospitalisation status after sustaining a mild/moderate injury in a vehicle-related crash.