OBJECTIVE: Symptoms of irritable bowel syndrome (IBS) are common in inflammatory bowel disease (IBD) and are believed to reflect ongoing inflammation. Consequently, a low prevalence of IBS-type symptoms in IBD patients with normal inflammatory markers is expected. We aimed to investigate the prevalence of IBS-type symptoms in IBD patients in biochemical remission (evidenced by low fecal calprotectin levels) and the relationship of these symptoms with fecal calprotectin levels. PATIENTS AND METHODS: In this observational, cross-sectional study, we included all adults with a history of IBD who had calprotectin levels less than 200 µg/g during routine follow-up between August 2014 and May 2015 at our hospital. Patients were excluded if calprotectin was measured because of gastrointestinal complaints. All patients were approached by telephone to evaluate the presence of IBS-type symptoms using Rome III questionnaires. Patients fulfilling IBS criteria were subclassified according to bowel habits. RESULTS: In total, 74 patients were included; 33 (45%, 95% confidence interval: 34-56%) fulfilled the IBS criteria. A larger proportion of Crohn's disease patients with IBS-type symptoms had ileal disease compared with Crohn's disease patients without IBS symptoms (55 vs. 24%; P=0.03). Other characteristics were similar between groups. No difference was found in calprotectin levels between patients with and without IBS-type symptoms (P=0.91). The majority of patients with IBS-type symptoms had diarrhea-predominant or mixed-type IBS (64 and 27% of patients with IBS-type symptoms, respectively). CONCLUSION: The prevalence of IBS-type symptoms in IBD patients in biochemical remission is high. A significant proportion of IBS-type symptoms is unrelated to ongoing inflammation and probably reflects 'true IBS'.