Purpose: To analyze commercial payer differences in the average costs and readmission rates between inpatient open hysterectomies and three types of outpatient hysterectomies: laparoscopic, laparoscopic assisted, and vaginal. Design/Methodology: A retrospective claims data analysis was conducted using the 2012 and 2013 Truven Health Analytics MarketScan Commercial Claims and Encounter Database. The study was limited to women 18-64 years old who had pharmacy coverage, 12 months of commercial insurance coverage in 2012, and at least 1 month in 2013. Readmission costs were capped at $100,000 and outpatient hysterectomy costs were adjusted to be on the same basis as open costs based on the portion of cancer cases, geographic region, and risk profile. Results: There were 21,926 hysterectomy cases meeting our criteria. Total average allowed costs for the day of surgery and 30 days following surgery were statistically significantly higher for inpatient open hysterectomies than outpatient hysterectomies (cost differences of $1,270 for laparoscopic, $2,764 for assisted laparoscopic, and $4,582 for vaginal; P<.001 for all comparisons). Readmission rates within 30 days following surgery were statistically significantly higher for inpatient open hysterectomies (3.05 per 100 cases) than those for outpatient laparoscopic (2.10 per 100 cases; P<.001) and assisted laparoscopic (2.17 per 100 cases; P=.01) hysterectomies, but not for vaginal hysterectomies (2.46 per 100 cases; P=.16). Conclusion: Inpatient open hysterectomies have statistically significantly higher average allowed costs than outpatient laparoscopic, laparoscopic assisted, and vaginal hysterectomies and statistically significantly higher readmission rates than outpatient laparoscopic and laparoscopic-assisted hysterectomies.