The following study examined the association between race, ethnicity, referral source, and reasons for attrition from substance use treatment in a sample of 72,643 discharges of adolescent youth in the United States from 2014 to 2016. Black and Hispanic adolescents were more likely to be discharged due to incarceration and termination by the facility compared to White adolescents. Adolescents referred by probation, diversion, other juvenile justice organizations, health care providers, community agencies, and individual referrals were significantly more likely to be discharged due to incarceration and terminated by the treatment facility compared to youth who were referred by schools. Findings suggest that enhancing linkage to treatment from systems in the social environment may play a role in attenuating racial and ethnic disparities in rates of attrition from substance abuse treatment among adolescent youth in the United States.