Abstract Background Hospital readmissions are frequent and expensive. Thirty-day readmission rates for adult patients undergoing colectomy are as high as 25%, with inflammatory bowel disease (IBD) being a major risk factor for readmission. We sought to 1) determine the 30-day readmission rate for pediatric patients with ulcerative colitis (UC) undergoing total abdominal colectomy (TAC) between 2012 and 2017 using a national pediatric surgical database and 2) identify risk factors for unplanned readmission in this population. Methods We used the National Surgical Quality Improvement Program-Pediatrics (NSQIP-P) to identify pediatric UC patients undergoing a TAC between 2012 and 2017. The NSQIP-P is a national, multi-center effort by the American College of Surgeons to improve surgical care through standardized collection of patient-level data and longitudinal 30-day monitoring of patients following surgery. We identified patient and procedural data from the index hospitalization and used logistic regression to identify risk factors for 30-day readmission rates, adjusting for confounding factors. Results We identified 489 pediatric UC TAC hospitalizations between 2012 and 2017. Among these, 19% were readmitted unexpectedly to the hospital within 30-days of discharge. Patient demographics and preoperative lab values (hematocrit, albumin) were not associated with risk of readmission. However, TAC procedures that included a proctectomy were at a 2-fold (95% CI, 1.2–3.8) higher risk of 30-day readmission than staged procedures after adjusting for patient demographics, index admission length of stay, operative time, pediatric surgeon, and laparoscopic versus open approach. Conclusion Nearly 20% of annual pediatric UC hospitalizations involving a colectomy result in an unplanned readmission within 30 days of hospital discharge. Notably, TAC procedures that included a proctectomy had significantly higher rates of readmission than those not including a proctectomy. These results can inform risk management strategies aimed at reducing morbidity and hospital readmissions for children with UC.