Background: Prospectively and systematically collected real-world data on vedolizumab are scarce. We aimed to assess the long-term clinical effectiveness of vedolizumab in inflammatory bowel disease (IBD). Methods: This study was a prospective, observational, multicentre study. Overall, 286 patients with active IBD were included (Crohn’s disease, n = 169; ulcerative colitis, n = 117). The primary outcomes were clinical response at week 12 and clinical remission at week 52, based on the Harvey Bradshaw Index and the partial Mayo Clinic score. Secondary outcomes included clinical remission at week 12, clinical response at week 52, corticosteroid-free clinical remission at week 52, changes in biochemical measures, and health-related quality of life (HRQoL). Results: At baseline, 88% of the patients were exposed to anti-TNF and 41% of the patients with Crohn’s disease had undergone ⩾1 surgical resection. At week 12, clinical response was 27% and remission 47% in Crohn’s disease; corresponding figures in ulcerative colitis were 52% and 34%. Clinical response, remission and corticosteroid-free remission at week 52 were 22%, 41% and 40% in Crohn’s disease and 49%, 47% and 46% in ulcerative colitis, respectively. A statistically significant decrease in median faecal-calprotectin and C-reactive protein was observed at 12 and 52 weeks in patients with Crohn’s disease and ulcerative colitis. The HRQoL measures Short Health Scale and EuroQol 5-Dimensions improved in both Crohn’s disease and ulcerative colitis patients ( p < 0.001). Clinical disease activity at baseline was inversely associated with clinical remission at week 52. Conclusion: Vedolizumab proved effective for the treatment of refractory IBD in clinical practice.