AIM: The aim of this study was to describe the incidence of complicated appendicitis during the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic lockdown. METHODS: This was a retrospective study of pediatric patients diagnosed with acute appendicitis in a single pediatric institution that assumed care responsibility for most of the pediatric emergencies during the lockdown period in Madrid (Spain). A control group was made up of the same number of patients diagnosed the previous year. RESULTS: One hundred fifty-one patients diagnosed with acute appendicitis were included (77 during self-quarantine and 74 during the previous year). The incidence of complicated appendicitis was 38.9% versus 28.3%, showing no significant differences. The 2 groups were homogeneous, with no differences in time elapsed between symptom onset and first emergency department visit, laboratory test results, median length of stay, intensive care admissions, or patients correctly diagnosed on their first visit. CONCLUSIONS: COVID-19 (coronavirus disease 2019) self-quarantine has not increased the incidence of complicated appendicitis, and children who developed complicated appendicitis did not have worse clinical outcomes. Parents did not delay presenting for medical attention, and emergency department pediatricians did not fail to diagnose this condition. Reorganization of hospital resources, fast-track treatment protocols for noncomplicated appendicitis, and extended use of home-stay hospitalization for complicated appendicitis could have contributed to these favorable outcomes.