Despite associations between ethnic-racial identity processes (i.e., exploration and resolution) and positive psychosocial outcomes among adolescents, limited empirical research investigates longitudinal associations between these processes and civic beliefs. To address this gap in the literature, this research explored whether changes in ethnic-racial identity exploration and resolution predicted civic beliefs among adolescents. Participants included 400 Latinx (n = 121; 47.1% girls) and Black American (n = 279; 52.0% girls) adolescents in the 6th (n = 210), 7th (n = 113) and 8th Grades (n = 74). Neither initial levels nor changes in ethnic-racial identity exploration predicted civic beliefs across four time-points of the study, or across two years of middle school. Adolescents who demonstrated greater increases in ethnic-racial identity resolution across two years of middle school were likely to have greater civic beliefs by the end of the two years, as compared to adolescents who had smaller increases in resolution. These results suggest that adolescents who have an increasingly clear sense of their ethnic-racial selves may have greater access to cognitive and socioemotional resources that promote their development of beliefs on the need to advance the well-being of their communities.