<h3>BACKGROUND CONTEXT</h3> Navigation (NAV) has been increasingly utilized to treat degenerative disease, with improvements in radiographic accuracy and positive clinical outcomes, despite increased OR time. Short-term outcomes research in degenerative populations has demonstrated fewer adverse events and reoperations with NAV. However, short-term analysis on treating adult deformity with NAV is limited, particularly using large nationally-represented cohorts. This is the first large-scale database study to compare short-term outcomes in adult deformity with and without NAV. <h3>PURPOSE</h3> To evaluate for 30-day readmission, reoperation, and morbidity, predictors of outcomes, and value per unit of time for adults undergoing deformity fusion with and without NAV. <h3>STUDY DESIGN/SETTING</h3> Retrospective database study using the 2005-2018 NSQIP datasets. <h3>PATIENT SAMPLE</h3> Adults who underwent posterior deformity surgery, who were identified in the NSQIP datasets using CPT codes 22800-22804 and were excluded if they had anterior, nonelective or lesion-related surgery. <h3>OUTCOME MEASURES</h3> Primary outcomes were 30-day readmission, reoperation, overall morbidity. Secondary outcomes were specific complications and total mean RVUs and RVUs per minute for NAV and conventional cases. Predictors of primary outcomes were also evaluated for. <h3>METHODS</h3> Univariate and multivariate regression analyses were used to compare readmission, reoperation, morbidity, and specific complications between NAV and conventional surgery, and to control for significant predictors and baseline differences between patients. Reoperation reasons were obtained from ICD and CPT codes for reoperation provided by NSQIP, if available. <h3>RESULTS</h3> Of 3,600 NSQIP patients with deformity surgery from 2005-2018, 3,190 met inclusion and exclusion criteria (161 with NAV). Patients were similar at baseline. NAV cases had greater OR time (405 vs 320 min) and RVUs (81.3 vs 69.7) (p<0.001), and were more likely to have pelvic fixation (26.1 vs 13.4%) and osteotomy (50.3 vs 27.7%) (p<0.001). In univariate analysis, NAV had greater reoperation (9.9 vs 5.2%, p=0.011), morbidity (57.8 vs 46.8%, p=0.007), and transfusion (52.2 vs 41.8%, p=0.010) rates. Readmission was similar (11.9 vs 8.4%). In multivariate analysis, NAV independently predicted reoperation (OR=1.792, p=0.048, CI95: 1.004-3.197), but no longer predicted morbidity or transfusion. Most reoperations were wound and hardware-related. Rehabilitation discharge (OR=1.852) and hospital stay (OR=1.056) predicted reoperation (p<0.001). Female gender (OR=1.335, p=0.004), OR time (OR=1.006, p<0.001), RVUs (OR=1.004, p=0.033), pelvic fixation (OR=1.818, p<0.001), and osteotomy (OR=1.481, p=0.001) predicted morbidity. Smoking was protective of morbidity (OR=0.649, p<0.001). <h3>CONCLUSIONS</h3> Despite controlling for patient-related and procedural factors, NAV independently predicted a 79% increased-odds of reoperation, but no longer predicted morbidity or transfusion. Readmission was similar between groups. This is most likely explained, in part, by greater OR time and transfusion, which are known risk factors for infection. Reoperation most frequently occurred for wound and hardware-related reasons, suggesting NAV carries an increased-risk of infectious-related events beyond increased OR time. Further, we identified factors associated with poorer outcomes, which can be targeted in at-risk patients. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.