BACKGROUND While ileal pouch anal anastomosis (IPAA) is the recommended way to restore intestinal continuity after total proctocolectomy, straight ileoanal anastomoses (SIAA) are still selectively performed, especially in the pediatric population. In case of SIAA failure, conversion to IPAA is possible, but reports on its outcomes are scarce. METHODS We retrospectively analyzed our prospectively collected database on pelvic pouches, and identified patients with a SIAA that was converted to IPAA. Our aim was long-term functional outcomes. RESULTS Twenty-three patients were included (14 females, median age at SIAA 15 years, median age at conversion to IPAA 19 years). The indication for SIAA was ulcerative colitis in 17 (74%) cases, indeterminate colitis in 2 (9%) cases, and familial adenomatous polyposis in 4 (17%) cases. The indication for IPAA conversion was incontinence/poor quality of life in 12 (52%) cases, sepsis in 8 (35%) cases, anastomotic stricture in 2 (9%) cases, and prolapse in one (4%) case. The majority were diverted at IPAA conversion (22, 96%). Three (13%) patients never had stoma closure, due to patient wishes, failed healing of vaginal fistula, and pelvic sepsis, respectively. After a median follow up of 109 months (28-170), pouch failure occurred in 5 additional patients. Overall pouch survival was 71% at 5 years. Median quality of life was 8/10, of health 8/10, and of energy 7/10. Median satisfaction with surgery was 9.5/10. CONCLUSIONS Conversion of SIAA to IPAA leads to acceptable long-term outcomes and good quality of life, and can safely be offered to patients with problems related to SIAA. METHODS IV.