The purpose of the study was to estimate the burden to families of raising a child with attention-deficit/hyperactivity disorder (ADHD). Data were drawn from a longitudinal sample recruited in western Pennsylvania. When participants were between 14 and 17 years old, parents completed a questionnaire assessing economic burden over the course of raising their children. Domains of economic burden to families included direct costs related to child’s behaviors (excluding treatment expenses) and indirect costs related to caregiver strain. On average, participants with ADHD incurred a total economic burden over the course of child development that was more than five times greater compared to youths without ADHD (ADHD = $15,036 per child, Control = $2,848 per child), and this difference remained significant after controlling for intellectual functioning, oppositional defiant symptoms, or conduct problems. Parents of participants with ADHD were more likely to have changed their job responsibilities or been fired and reported lower work efficiency. The current evaluation of economic burden to individual families extends previous estimates of annual societal cost of illness (COI) of ADHD. Our rough annual estimate of COI for ADHD in children and adolescents is $124.5 billion (2017 US Dollars). Findings underscore the need for interventions to reduce the costly dysfunctional outcomes in families of children with ADHD.