ObjectiveTo assess the outcomes, total healthcare utilization, and cost savings for same-day discharge versus inpatient robotic assisted partial nephrectomy (RAPN) and robotic assisted radical nephrectomy (RARN). MethodsWe compared 146 RAPNs and 65 RARNs consecutively performed as same-day discharge (RAPN=21, RARN=9) versus inpatient (RAPN=125, RARN=56) from April 2015 to May 2023 at two academic medical centers. We collected baseline demographics, perioperative characteristics, and 30-day complications. We applied the Time-Driven Activity-Based Costing (TDABC) analysis to compare total costs of RAPN and PARN throughout the cycle of care, including inpatient vs same-day discharge. ResultsBaseline demographics and comorbidities were similar between patients undergoing inpatient versus same-day discharge RAPN and RARN. One Clavien-Dindo grade II complication (3.3%) requiring re-admission due to wound infection for antibiotics occurred after same-day discharge RAPN; no complications occurred after same-day discharge RARN. Two unscheduled office or ED visits (6.7%) occurred after same-day discharge RAPN for surgical-site infection and urinary retention. Same-day discharge versus inpatient RAPN and RARN demonstrated a $3,091 (18%) and $4,003 (25%) overall cost reduction, respectively. ConclusionSame-day discharge RAPN and RARN result in cost savings of 18-25% without a difference in complications, and thereby improves value-based care for appropriately selected patients.