Among many in the research, policy, and practice communities, the application of sex offender registration and notification (SORN) to juveniles who sexually offend (JSO) has raised ongoing concerns regarding the potential collateral impacts on youths’ social, mental health, and academic adjustment. To date, however, no published research has systematically examined these types of collateral consequences of juvenile SORN. Based on a survey of a national sample of treatment providers in the United States, this study investigates the perceived impact of registration and notification on JSO across five key domains: mental health, harassment and unfair treatment, school problems, living instability, and risk of reoffending. Results indicate that treatment providers overwhelmingly perceive negative consequences associated with registration with an incremental effect of notification indicating even greater concern across all five domains. Providers’ demographics, treatment modalities, and client profile did not influence their perceptions of the collateral consequences suggesting that provider concern about the potential harm of SORN applied to juveniles is robust. Policy implications are discussed.