OBJECTIVE Nontraumatic spinal cord injury (SCI) represents a significant proportion of individuals admitted for SCI rehabilitation; however, there is limited literature regarding their outcomes. As our society continues to age and nontraumatic injuries present with greater frequency, further studies in this area will become increasingly relevant. The objective of this study was to compare outcomes of patients with nontraumatic SCI with those with traumatic SCI after inpatient rehabilitation. METHODS A longitudinal study with matched block design was used comparing 86 patients with nontraumatic SCI admitted to a SCI rehabilitation unit and 86 patients with traumatic SCI admitted to regional model SCI centers, controlling for age, neurologic level of injury, and American Spinal Injury Association impairment classification. Main outcome measures included acute and rehabilitation hospital length of stay, FIM scores, FIM change, FIM efficiency, rehabilitation charges, and discharge-to-home rates. RESULTS Results indicate that when compared with traumatic SCI, patients with nontraumatic SCI had a significantly (P < 0.01) shorter rehabilitation length of stay (22.38 vs. 41.35 days) and lower discharge FIM scores (57.3 vs. 65.6), FIM change (18.6 vs. 31.0), and rehabilitation charges ($25,050 vs. $64,570). No statistical differences were found in acute care length of stay, admission FIM scores, FIM efficiency, and community discharge rates. CONCLUSIONS The findings indicate that patients with nontraumatic SCI can achieve rates of functional gains and community discharge comparable with traumatic SCI. Whereas patients with traumatic SCI achieved greater overall functional improvement, patients with nontraumatic SCI had shorter rehabilitation length of stay and lower rehabilitation charges. These findings have important implications for the interdisciplinary rehabilitation process in the overall management and outcome of individuals with nontraumatic SCI.