OBJECTIVE: To perform an econometric analysis to examine the influence of procedure volume, variation in hospital accounting methodology, and use of various analytic methodologies on cost of robotically assisted hysterectomy for benign gynecologic disease and endometrial cancer. METHODS: A national sample was used to identify women who underwent laparoscopic or robotically assisted hysterectomy for benign indications or endometrial cancer from 2006 to 2012. Surgeon and hospital volume were classified as the number of procedures performed before the index surgery. Total costs as well as fixed and variable costs were modeled using multivariable quantile regression methodology. RESULTS: A total of 180,230 women, including 169,324 women who underwent minimally invasive hysterectomy for benign indications and 10,906 patients whose hysterectomy was performed for endometrial cancer, were identified. The unadjusted median cost of robotically assisted hysterectomy for benign indications was $8,152 (interquartile range [IQR] $6,011-10,932) compared with $6,535 (IQR $5,127-8,357) for laparoscopic hysterectomy (P<.001). The cost differential decreased with increasing surgeon and hospital volume. The unadjusted median cost of robotically assisted hysterectomy for endometrial cancer was $9,691 (IQR $7,591-12,428) compared with $8,237 (IQR $6,400-10,807) for laparoscopic hysterectomy (P<.001). The cost differential decreased with increasing hospital volume from $2,471 for the first 5 to 15 cases to $924 for more than 50 cases. Based on surgeon volume, robotically assisted hysterectomy for endometrial cancer was $1,761 more expensive than laparoscopy for those who had performed fewer than five cases; the differential declined to $688 for more than 50 procedures compared with laparoscopic hysterectomy. CONCLUSION: The cost of robotic gynecologic surgery decreases with increased procedure volume. However, in all of the scenarios modeled, robotically assisted hysterectomy remained substantially more costly than laparoscopic hysterectomy.