BACKGROUND: Subcutaneous infliximab may provide multiple benefits over intravenous formulations. However, there is uncertainty about the relative efficacy in inflammatory bowel disease (IBD). AIM: To evaluate the relative efficacy of intravenous versus subcutaneous infliximab in patients with IBD using clinical response, clinical remission, and endoscopic remission outcomes at 30- and 54-week outcomes. METHODS: We conducted a systematic review and network meta-analysis with results up to August 2024. We calculated comparative efficacy using surface under the cumulative ranking curve (SUCRA), posterior probability, and contrast plots. RESULTS: A total of 9 studies with 2519 patients met the selection criteria for inclusion; 33.6% (846/2519) of patients had Crohn's disease and 66.4% (1673/2519) had ulcerative colitis. Via SUCRA analysis, subcutaneous infliximab was ranked first in all comparisons. Via posterior probability modelling, there was strong or very strong evidence of superiority with subcutaneous over intravenous infliximab for clinical response (30-week outcomes), clinical remission (30- and 54-week outcomes), although with moderate evidence for clinical response at 54 weeks, and no evidence of any difference for endoscopic remission (54 weeks). Via contrast plot analysis, no comparison reached statistical significance. CONCLUSION: Subcutaneous infliximab is associated with high efficacy rates in IBD. Subcutaneous infliximab may offer clinical benefit above the intravenous formulation. This should provide patients and clinicians with confidence in using subcutaneous infliximab in IBD. Further head-to-head trials are needed to confirm the relative efficacy between these formulations.