Readmission rates in postoperative patients are an important health economic and clinical challenge faced in the modern NHS, with financial levies attached. In America since 2013, hospitals have been faced with ‘readmission penalties’ deducted from Medicare reimbursements. This was the inspiration behind this multi-institutional comparison of 30-day postoperative complication and readmission rates between open retropubic radical prostatectomy (RRP) and robot assisted laparoscopic radical prostatectomy (RALRP). Authors utilised the National Surgical Quality Improvement Program (NQIP) database for 2011. The NQIP is a national, multi-institutional, validated and comprehensive database that reports surgical complications with data collected preoperative through 30 days postoperatively. All laparoscopic prostatectomy cases were excluded, and therefore, of the 5471 cases analysed, 4374 (79.9%) and 1097 (20.1%) underwent RALRP and RRP, respectively. The overall complication rate for RRP patients was 23.2% and RALRP was 5.62%. The surgical complication rate for RRP was 3.37% and RALRP was 0.91%. RRP patients were more likely to be readmitted, suffer increased overall complication rates and increased surgical site complications (wound dehiscence, superficial and deep infection). RRP patients were more likely to suffer non-surgical site complications, including myocardial infarction, pneumonia, blood transfusion requirements and sepsis. Rates of perioperative venous thromboembolism and cardiac arrest were comparable. Operating room time was shorter for RRP and re-operation rates did not significantly differ between cohorts (1.09% vs. 0.96%). RRP and RALRP experienced different readmission rates (5.47% vs. 3.48%, respectively). The authors concluded that age, operative time, and undergoing RRP were significant predictors of readmission on multivariate analysis. Important data, regarding a number of variables including preoperative anti-platelet therapy, tumour characteristics and the experience of surgeons involved, is missing. Nonetheless, this study is further evidence that patients undergoing RALRP have fewer complications and readmissions compared to the traditional open RRP approach.