BACKGROUND Vedolizumab (VDZ), a humanised monoclonal antibody that selectively inhibits alpha4-beta7 integrins is approved for use in adult moderate to severe ulcerative colitis (UC) patients. AIM To assess the efficacy and safety of VDZ in the real-world management of UC in a large multicenter cohort involving two countries and to identify predictors of achieving remission. METHODS A retrospective review of Australian and Oxford, United Kingdom data for UC patients. Clinical response at 3 mo, endoscopic remission at 6 mo and clinical remission at 3, 6 and 12 mo were assessed. Cox regression models and Kaplan Meier curves were performed to assess the time to remission, time to failure and the covariates influencing them. Safety outcomes were recorded. RESULTS Three hundred and three UC patients from 14 centres in Australia and United Kingdom, [60% n = 182, anti-TNF naïve] were included. The clinical response was 79% at 3 mo with more Australian patients achieving clinical response compared to Oxford (83% vs 70% P = 0.01). Clinical remission for all patients was 56%, 62% and 60% at 3, 6 and 12 mo respectively. Anti-TNF naive patients were more likely to achieve remission than exposed patients at all the time points (3 mo 66% vs 40% P < 0.001, 6 mo 73% vs 46% P < 0.001, 12 mo 66% vs 51% P = 0.03). More Australian patients achieved endoscopic remission at 6 mo compared to Oxford (69% vs 43% P = 0.01). On multi-variate analysis, anti-TNF naïve patients were 1.8 (95%CI: 1.3-2.3) times more likely to achieve remission than anti-TNF exposed (P < 0.001). 32 patients (11%) had colectomy by 12 mo. CONCLUSION VDZ was safe and effective with 60% of UC patients achieving clinical remission at 12 mo and prior anti-TNF exposure influenced this outcome.