Characterize the early trajectories of financial functioning in adults with history of childhood ADHD and use these trajectories to project earnings and savings over the lifetime. Data were drawn from a prospective case-control study (PALS) following participants with a rigorous diagnosis of ADHD during childhood (N = 364) and demographically matched controls (N = 240) for nearly 20 years. Participants and their parents reported on an array of financial outcomes when participants were 25 and 30 years old. At age 30, adults with a history of ADHD exhibited substantially worse outcomes than controls on most financial indicators, even when they and their parents no longer endorsed any DSM symptoms of ADHD. Between ages 25 and 30, probands had exhibited considerably slower growth than controls in positive financial indicators (e.g., monthly income) and substantially less reduction than controls in indicators of financial dependence (e.g., living with parents), indicating worsening or sustained deficits on nearly all measures. When earnings trajectories from age 25 to age 30 were extrapolated using matched census data, male probands were projected to earn $1.27 million less than controls over their working lifetime, reaching retirement with up to 75% lower net worth. The financial deficit of adults with history of childhood ADHD grows across early adulthood. Projections based on early financial trajectories suggest very large cumulative differences in earnings and savings. With or without persistence of the DSM symptoms, the adult sequela of childhood ADHD can be conceptualized as a chronic condition often requiring considerable support from others during adulthood. (PsycINFO Database Record (c) 2020 APA, all rights reserved).