Few studies provide information about the clinical correlates of economic costs in pediatric anxiety disorders. This study uses baseline data from a randomized trial involving 209 children and adolescents with clinical anxiety to examine clinical and demographic correlates of direct and indirect costs. Measured costs included the direct costs of mental health services and the indirect costs resulting from children’s missed school and parents’ missed work. Validated measures of anxiety and depression severity and of internalizing and externalizing behaviors were reported by youth, their parents, and independent evaluators. Seventy-two percent of youth (n = 150) had positive costs. Among these youth, the mean annual total cost was $6405 (sd = $11,674), of which $5890 represented direct cost and $4658 represented indirect cost. Higher average costs were correlated with greater child anxiety and depression severity (p < 0.001). Most pediatric anxiety disorders result in substantial individual and family costs, and costs may increase rapidly with elevated anxiety severity and depressed mood.