Associations between adolescent civic and organized activities (volunteering, standard political, social movement, school/community, religious) and civic beliefs (comprised of should, obligation, and respect judgments) were examined. Cross‐sectional models (N = 703, Mage = 15.87) indicated domain specificity between adolescent civic beliefs and behaviors. Longitudinal models (n = 219, Mage = 15.39) indicated that adolescents' standard political beliefs predicted greater levels of standard political involvement one year later, and school/community activities predicted greater standard political beliefs a year later. Youth volunteering predicted lower standard political beliefs, and standard political involvement predicted lower community service beliefs one year later. Findings support the assessment of adolescent sociomoral civic beliefs and demonstrate how civic experiences and civic beliefs can mutually promote each other during adolescence.