OBJECTIVE: To describe the COVID-19 pandemic's impact on acute appendicitis management on children and young people (CYP). DESIGN: Retrospective cohort study. SETTING: All English National Health Service hospitals. PATIENTS: Acute appendicitis admissions (all, simple, complex) by CYP (under-5s, 5-9s, 10-24s). EXPOSURE: Study pandemic period: February 2020-March 2021. Comparator pre-pandemic period: February 2015-January 2020. MAIN OUTCOME MEASURES: Monthly appendicectomy and laparoscopic appendicectomy rate trends and absolute differences between pandemic month and the pre-pandemic average. Proportions of appendicitis admissions comprising complex appendicitis by hospital with or without specialist paediatric centres were compared. RESULTS: 101 462 acute appendicitis admissions were analysed. Appendicectomy rates fell most in April 2020 for the 5-9s (-18.4% (95% CI -26.8% to -10.0%)) and 10-24s (-28.4% (-38.9% to -18.0%)), driven by reductions in appendicectomies for simple appendicitis. This was equivalent to -54 procedures (-68.4 to -39.6) and -512 (-555.9 to -467.3) for the 5-9s and 10-24s, respectively. Laparoscopic appendicectomies fell in April 2020 for the 5-9s (-15.5% (-23.2% to -7.8%)) and 10-24s (-44.8% (-57.9% to -31.6%) across all types, which was equivalent to -43 (-56.1 to 30.3) and -643 (-692.5 to -593.1) procedures for the 5-9s and 10-24s, respectively. A larger proportion of complex appendicitis admissions were treated within trusts with specialist paediatric centres during the pandemic. CONCLUSIONS: For CYP across English hospitals, a sharp recovery followed a steep reduction in appendicectomy rates in April 2020, due to concerns with COVID-19 transmission. This builds on smaller-sized studies reporting the immediate short-term impacts.