Objective: To evaluate rates of presentation, neuroimaging, therapies, and serious neurologic disorders (SNDs) among children and young adults presenting to the emergency department with headache. Methods: We performed a cross-sectional study of a nationally representative sample survey of visits to US emergency departments between 2002 and 2017. We identified encounters of patients ≤25 years old with chief complaint of headache. We report the rates of presentation, imaging, and treatments and report proportions having concomitant diagnoses of serious neurologic disorders. Results: Among encounters ≤25 years, 2.0% had a chief complaint of headache, with no change in the yearly rates of encounters ( P = .98). Overall, 20.8% had a head computed tomography (CT), with a reduction in performance between 2007 and 2016 ( P < .01). One-quarter (25.2%, 95% confidence interval [CI] 22.2%-28.3%) were given narcotics and 2.5% (95% CI 1.7%-3.2%) had serious neurologic disorders. Conclusion: Overall, 2.0% of emergency department encounters among patients ≤25 years were for headache, with low rates of serious neurologic disorders. CT use appeared to be declining.