© 2015, The Society for Surgery of the Alimentary Tract. Objective: The objective of this study is to characterize UC patients undergoing RP and identify causes and risk factors for readmission.Design: A retrospective review of a prospectively maintained institutional database was performed. Postoperative readmission rates and reasons for readmission were examined following RP. Univariate and multivariate analyses were performed to evaluate for risk factors associated with readmission.Results: Of 533 patients who met our inclusion criteria, 18.2 % (n = 97) were readmitted within 30 days while 22.7 % (n = 121) were readmitted within 90 days of stage I of RP. Younger patient age (OR 1.825, 95 % CI 1.139–2.957), laparoscopic approach (OR 1.943, 95 % CI 1.217–3.104), and increased length of initial stay (OR 1.155, 95 % CI 1.090–1.225) were all associated with 30-day readmission. The most common reason for readmission was dehydration/ileus/partial bowel obstruction, with 10 % of patients readmitted for this reason within 30 days.Conclusions: Patients undergoing restorative proctocolectomy are at high risk for readmission, particularly following the first stage of the operation. Novel treatment pathways to prevent ileus and dehydration as an outpatient may decrease the rates of readmission following RP.Background: Postoperative readmissions increase costs and affect patient quality of life. Ulcerative colitis (UC) patients are at a high risk for hospital readmission following restorative proctocolectomy (RP).