Background: In 2014, inpatient spinal fusion surgery had the highest aggregate cost of any inpatient surgery performed in the United States, costing 12 billion dollars. As the national health care system seeks to improve valuebased care, there is increased motivation to perform surgery on an outpatient basis. To ensure improved patient outcomes with this transition, patient selection has become increasingly important to identify who would most benefit from outpatient spine fusion, for example. This demands an improved understanding of the demographics of patients who have been receiving outpatient spine fusion on which the spine surgery community can build to improve costeffective care delivered.Methods: The Healthcare Cost and Utilization Project, State Ambulatory Surgery Databases, and Agency for Healthcare Research and Quality databases were queried for demographic data regarding all-cause outpatient spine surgery between 2012 and 2014. Outpatient surgery volume was compared with inpatient surgery volume-which was provided by the State Inpatient Databases.Results: A total of 1,164,040 spine fusion procedures were identified between 2012 and 2014, of which 132,900 procedures were performed as outpatient surgery (11.4%). Of all fusion procedures amongst 18-to 44-year-old patients, 18.4% were outpatient. A larger proportion of white patients, rather than black or Hispanic patients, underwent ambulatory procedures (12.14% vs 9.53% vs 7.46%, respectively); 16.54% of spinal fusion procedures for patients with private insurance was performed on an outpatient basis. Based on patient income, 76% of all outpatient fusions were performed on patients who live in ''not low'' income ZIP codes.Conclusions: There has been a gradual trend toward performing more outpatient spinal fusion procedures over the studied period. This study has also revealed unique trends in the demographics of patients who have received outpatient spine fusion during this time.Level of Evidence: 3.