To evaluate how the introduction of robotic-assisted surgery affects treatment-related morbidity and cost of endometrial cancer (EC) staging.We retrospectively reviewed the records of consecutive patients with stage I-III EC undergoing surgical staging between 2007 and 2012 at our institution. Costs (from surgery to 30days after surgery) were set based on the Medicare cost-to-charge ratio for each year and inflated to 2014 values. Inverse probability weighting (IPW) was used to decrease the allocation bias when comparing outcomes between surgical groups.We focused our analysis on the 251 EC patients who had robotic-assisted surgery and the 384 who had open staging. During the study period, the use of robotic-assisted surgery increased and open staging decreased (P0.001). Correcting group imbalances by using IPW methodology, we observed that patients undergoing robotic-assisted staging had a significantly lower postoperative complication rate, lower blood transfusion rate, longer median operating time, shorter median length of stay, and lower readmission rate than patients undergoing open staging (all P0.001). Overall 30-day costs were similar between the 2 groups, with robotic-assisted surgery having significantly higher median operating room costs ($2820 difference; P0.001) but lower median room and board costs ($2929 difference; P0.001) than open surgery. Increasing experience with robotic-assisted staging was significantly associated with a decrease in median operating time (P=0.002) and length of stay (P=0.003).The implementation of robotic-assisted surgery for EC staging improves patient outcomes. It provides women the benefits of minimally invasive surgery without increasing costs and potentially improves patient turnover.