Research on multiracial individuals is often cross-sectional, obscuring the fluid nature of multiracial self-categorization across time. Pathways of racial self-identification are developed from a nationally representative sample of adolescents aged 14-18, measured again 5 years later. A significant proportion of multiracial adolescents change racial self-identification across time. Youth who ever report being multiracial are 4 times as likely to switch self-identification as to report consistent multiracial identities. Across this time, more multiracial adolescents either add a racial category (diversify) or subtract one (consolidate) than maintain consistent multiracial self-categorization. Exploratory multinomial analyses show few differences between these pathways on select psychological and social characteristics. Results lend quantitative support to qualitative studies indicating the fluidity of racial self-categorization.