BACKGROUND AND AIMS: This study compares the effectiveness of different biologic therapies and sequences in patients with inflammatory bowel disease [IBD] using real-world data from a large cohort with long exposure. METHODS: Demographic, disease, treatment, and outcome data were retrieved for patients in the UK IBD BioResource. Effectiveness of treatment was based on persistence free of discontinuation or failure, analysed by Kaplan-Meier survival analysis with inverse probability of treatment weighting to adjust for differences between groups. RESULTS: In total, 13 222 evaluable patients received at least one biologic. In ulcerative colitis [UC] first-line vedolizumab [VDZ] demonstrated superior effectiveness over 5 years compared to anti-tumour necrosis factor [anti-TNF] agents [p = 0.006]. VDZ was superior to both infliximab [IFX] and adalimumab [ADA] after ADA and IFX failure respectively [p < 0.001 and p < 0.001]. Anti-TNF therapy showed similar effectiveness when used as first-line treatment, or after failure of VDZ. In Crohn's disease [CD] we found significant differences between first-line treatments over 10 years [p = 0.045], with superior effectiveness of IFX compared to ADA in perianal CD. Non-anti-TNF biologics were superior to a second anti-TNF after first-line anti-TNF failure in CD [p = 0.035]. Patients with UC or CD experiencing TNF failure due to delayed loss of response or intolerance had superior outcomes when switching to a non-anti-TNF biologic, rather than a second anti-TNF. CONCLUSIONS: We provide real-world evidence to guide biologic selection and sequencing in a range of common scenarios. Our findings challenge current guidelines regarding drug selection after loss of response to first anti-TNF treatment.