Introduction: Severe asthma in children is heterogeneous, and many remain poorly controlled despite optimized therapy . Asthma remission, a long-term outcome beyond symptom control, has gained attention. Low-dose azithromycin shows immunomodulatory effects in adults, but pediatric evidence across phenotypes is limited. Objective: To evaluate effectiveness and safety of add-on low-dose azithromycin in children with severe asthma and explore phenotype-specific remission outcomes. Methods: This real-world observational study included children with severe asthma diagnosed by GINA criteria. Patients received add-on azithromycin 10 mg/kg, three times weekly , for 3 months alongside standard therapy; remission was assessed over 12 months. Patients were classified as T2-high or T2-low based on clinical features and inflammatory markers (blood eosinophils, FeNO, IgE). Primary outcome: clinical remission, defined as no exacerbations, no oral corticosteroids in the preceding 6 months, and ACQ-5 ≤1 at 12 months. Secondary outcomes: clinical remission plus lung function remission (postbronchodilator FEV₁ ≥80% predicted or decline ≤5%) and complete remission (clinical + lung function remission plus sputum eosinophils