Outpatient shoulder arthroplasty presents potential clinical benefits but also risk without perioperative optimization. Length of stay depends largely on surgeon preferences, and a large single-surgeon cohort may provide insight into optimal strategies and costs for outpatient shoulder arthroplasty. A single-surgeon cohort of 472 anatomic and reverse shoulder arthroplasties performed between 2017 and 2020 was retrospectively reviewed. Cases were stratified by those who did or did not undergo same-day discharge. The 90-day readmission, discharge to post-acute care, cost, and 45 patient/case factors were examined. Two hundred fifty (53%) underwent same-day discharge, with the proportion of outpatient cases increasing over time to nearly 80%, with no significant difference in 90-day readmissions. Revision cases often underwent same-day discharge, whereas fractures were typically admitted. The cost was significantly higher for inpatients, with implants accounting for 52%. Surgeons may safely transition a substantial proportion of shoulder arthroplasties to same-day discharge with some reassurance regarding cost savings and 90-day readmissions. (Journal of Surgical Orthopaedic Advances 32(4):263-269, 2023).