BACKGROUND: A temporal relationship between vedolizumab and new-onset spondyloarthritis (SpA) has been suggested. AIMS: We evaluated the relationship between vedolizumab initiation and development of new-onset SpA in patients with inflammatory bowel disease (IBD) through serial clinical evaluation and magnetic resonance imaging (MRI). METHODS: A single-centre prospective observational study of 24 patients with IBD. Patients were eligible if they had active ulcerative colitis or Crohn's disease (CD), were initiating vedolizumab, had no prior history of arthritis or SpA and were suitable for serial MRI. A rheumatologist performed clinical evaluation prior to the first dose and 8 and 24 weeks. Axial MRI was evaluated by a blinded central reader and performed at baseline 8 and 24 weeks. RESULTS: Nine tumor necrosis factor (TNF) inhibitor-naive patients (4 male; mean age 53.2 years; 6 UC; 3 CD) and eight TNF inhibitor-experienced patients (7 male; mean age 48 years; 3 UC; 5 CD) completed all assessments. No patients developed new features of axial arthritis or features of peripheral SpA (inflammatory oligoarthritis, enthesitis, dactylitis, or psoriasis (nail, body, or scalp)). Both groups demonstrated a good intestinal response. CONCLUSION: Vedolizumab initiation did not induce new features of axial or peripheral SpA after 24 weeks of treatment in TNF inhibitor-experienced or TNF inhibitor-naive patients with IBD.