INTRODUCTION: Open ureteroneocystostomy (UNC) is the gold standard for surgical correction of vesicoureteral reflux (VUR). Beyond single-center reports, there are few published data on outcomes of minimally-invasive (MIS) UNC. Our objective was to compare postoperative outcomes of open and MIS UNC using national, population-level data. METHOD: We reviewed the 1998-2012 Nationwide Inpatient Sample to identify pediatric (≤18 years) VUR patients who underwent either open or MIS UNC. Demographics, National Surgical Quality Improvement Program (NSQIP) complications, length of stay (LOS), and cost data were extracted. Statistical analysis was performed using weighted, hierarchical multivariate logistic regression (complications) and negative binomial regression (LOS, cost). RESULTS: We identified 780 MIS and 75,976 open UNC admissions. Compared with patients undergoing open UNC, patients who underwent MIS UNC were likely to be older (6.2 versus 4.8 years, p < 0.001), publically insured (43 versus 26%, p < 0.001), and treated in recent years (90 versus 46% after 2005, p < 0.001). MIS admissions were associated with a significantly shorter length of stay (1.0 versus 1.8 days, p < 0.001) and higher cost ($9230 versus $6,304, p = 0.002). After adjusting for patient-level confounders (age, gender, insurance, treatment year, and comorbidity), and hospital-level factors (region, bedsize, and teaching status), MIS UNC was associated with a significantly higher rate of postoperative urinary complications such as UTIs, urinary retention, and renal injury (OR 3.1, p = 0.02), shorter LOS (RR 0.8, p = 0.02), and higher cost (RR 1.4, p = 0.008). DISCUSSION: Strengths of this study are its large cohort size, long time horizon, national estimation, and cost data. Most prior studies are case-series limited to the size of the institutional cohort. Our analysis of 76,756 operative encounters revealed that open UNC continues to be performed at far greater frequency than MIS UNC, outpacing the latter modality by nearly 100:1. Children treated with MIS UNC had three times greater odds of developing postoperative urinary complications, and MIS UNC patients incurred average costs per admission that were nearly 1.5 times higher than those of children who underwent open UNC. These children were also likely to be older, publically insured, and treated in more recent years. On the other hand, patients treated with MIS UNC required substantially shorter postoperative hospitalization, with an average LOS roughly half that of open UNC cases. Limitations include the retrospective nature of the administrative database, lack of detailed patient-level data, and no available long-term postoperative outcomes. Compared with open surgery, MIS UNC was associated with shorter LOS but higher costs and possibly higher urinary complication rates.