BACKGROUND: Thousands of neurosurgical emergencies are transferred yearly to tertiary care facilities to assume a higher level of care. Several studies have examined how neurosurgical transfers influence patient outcomes, but characteristics of potentially avoidable transfers have yet to be investigated. OBJECTIVE: To identify whether potentially avoidable transfers represent a significant portion of transfers to a tertiary neurosurgical facility. METHODS: In this cohort study, we evaluated 916 neurosurgical patients transferred to a tertiary care facility over a 2-year period. Transfers were classified as potentially avoidable when no neurosurgical diagnostic test, intervention, or intensive monitoring was deemed necessary (n 180). The remaining transfers were classified as justifiable (n 736). The main outcomes and measures were age, sex, diagnosis, insurance status, intervention, distance of transfer, length of hospital and intensive care unit stay, mortality, discharge disposition, and cost. RESULTS: Nearly 20% of transfers were identified as being potentially avoidable. Although some of these patients had suffered devastating, irrecoverable neurological insults, many had innocuous conditions that did not require transfer to a higher level of care. Justifiable transfers tend to involve patients with nontraumatic intracranial hemorrhage and cranial neoplasm. Both groups were admitted to the intensive care unit at the same rate (approximately 70% of patients). Finally, the direct transportation cost of potentially avoidable transfers was $1.46 million over 2 years. CONCLUSION: This study identified the frequency and expense of potentially avoidable transfers. There is a need for closer examination of the clinical and financial implications of potentially avoidable transfers.