Abstract Background The COVID-19 pandemic has had a large impact on regular healthcare provision in the Netherlands. During the first wave, healthcare in children was strongly reduced due to safety regulations and reduced hospital capacity for non-COVID care. This, and fear of COVID-19 could have led to delayed inflammatory bowel disease (IBD) healthcare, and delayed or even missed diagnoses. This has already been demonstrated in adult IBD patients in the Netherlands1, but not yet in the paediatric population. This is of importance, as in children, diagnostic delay is associated with higher rates of strictures, fistulising complications, and growth delay2. Therefore, this study aims to determine the impact of COVID-19 on IBD-related procedures and new IBD diagnoses in children in the Netherlands. Methods In this nationwide retrospective cohort study, a search was conducted in the nationwide pseudonymized pathology registry of the Netherlands (PALGA), with complete national coverage. Using retrieval terms for ulcerative colitis, Crohn’s disease, IBD unclassified and corresponding synonyms, all IBD related pathology reports (resection specimens or intestinal biopsies) from January 2018 to December 2020 in children age 1–18 were selected. Patients with a recognized diagnosis of IBD were eligible for inclusion, which was scored independently by two authors based on all reports. All IBD-related procedures (endoscopies and intestinal resections) were identified. Monthly frequencies of procedures and new IBD diagnoses during the COVID-19 pandemic in the Netherlands (March 11, 2020 – December 31, 2020) were compared to the average monthly frequencies of 2018–2019. Results After exclusion of non-IBD related reports, 2161 IBD-related procedures were identified between January 2018 and December 2020. The average number of monthly IBD procedures in 2018–2019 was 59.8, whereas in 2020 this was 60.6 procedures per month, reflecting a 0.8% increase (Figure 1). In 2020, the number of new IBD diagnoses was 456, similar to the ...