reast cancer is the second leading cause of cancer-related death in American women, with more than 4 million women living with the diagnosis and more than 300,000 new diagnoses each year in the United States. 1 Given the enormous burden of this disease, there is a continued need for timely detection, optimized treatment, and preserved quality of life after treatment. [2][3][4] To reduce the need for radiation therapy and lower rates of recurrence, surgical management Background: Patients undergoing immediate breast reconstruction with tissue expanders are frequently admitted after surgery for monitoring and pain control, which introduces additional costs and risks of nosocomial infection. Same-day discharge could conserve resources, mitigate risk, and return patients home for faster recovery. The authors used large data sets to investigate the safety of same-day discharge after mastectomy with immediate postoperative expander placement. Methods: A retrospective review was performed of patients in the National Surgical Quality Improvement Program database who underwent breast reconstruction using tissue expanders between 2005 and 2019. Patients were grouped based on date of discharge. Demographic information, medical comorbidities, and outcomes were recorded. Statistical analysis was performed to determine efficacy of same-day discharge and identify factors that predict safety. Results: Of the 14,387 included patients, 10% were discharged the same day, 70% on postoperative day 1, and 20% later than postoperative day 1. The most common complications were infection, reoperation, and readmission, which trended upward with length of stay (6.4% versus 9.3% versus 16.8%), but were statistically equivalent between same-day and next-day discharge. The complication rate for later-day discharge was statistically higher. Patients discharged later had significantly more comorbidities than same or next-day discharge counterparts. Predictors of complications included hypertension, smoking, diabetes, and obesity. Conclusions: Patients undergoing mastectomy with immediate tissue expander reconstruction are usually admitted overnight. However, same-day discharge was demonstrated to have an equivalent risk of perioperative complications as next-day discharge. For the otherwise healthy patient, going home the day of surgery is a safe and cost-effective option, although the decision should be made based on the individual patient.