Seasonal Trends in Emergency Department Visits for Mental and Behavioral Health Conditions Among Children and Adolescents Aged 5–17 Years — United States, January 2018–June 2023

What is already known about this topic? Mental and behavioral health conditions are common among school-aged children in the United States. What is added by this report? Each year, during 2018–2023, among children and adolescents aged 10–17 years, the number and proportion of weekly emergency department visits for eight mental and behavioral health conditions displayed seasonal increases during the fall and spring school semesters relative to the summer period; timing of increases varied by specific condition. What are the implications for public health practice? Systemic changes that prioritize protective factors, such as physical activity, social support, and inclusive school environments, and incorporate preparedness for increases in mental and behavioral health conditions during back-to-school planning might help improve child and adolescent mental health.