Background: Dropout from child and adolescent psychotherapy is a common phenomenon which can have negative consequences for the individual later in life. It is therefore important to gain insight on dropout risk factors. Objective: Several potential risk factors [ethnic minority status, a lower socioeconomic status (SES), and higher problem severity] were analyzed in present study. Innovations are that these risk factors were examined for children and adolescents separately, and a distinction was made in termination status between referred patients, dropouts and completers. Methods: For ethnic majority and minority outpatient children (age 5-11, n = 399) and adolescents (age 12-20, n = 352) problem severity, ethnic background, SES, and treatment termination status (completer, dropout, referral) were specified. Multinomial logistic regression models were used as main method of analysis. Results: For children, a Moroccan/Turkish ethnicity and higher externalizing scores were risk factors for being referred. For adolescents, a Surinamese/Antillean ethnicity, being female, being older, and lower parental SES occupation levels were risk factors for dropout. Conclusions: Different dropout risk profiles emerged for children versus adolescents, and for dropouts versus referrals. Also, it depended on the specific ethnic background whether ethnic minority status was a predictor for dropout, and the relationship between SES and termination status differed by whether parental SES occupation or parental SES education were used as SES indicator. Professionals should thus be aware of these potential risk factors for dropout or referral when treating children and adolescents.