OBJECTIVE: Addressing cost-related unmet health needs is critical to ensuring positive health outcomes in adolescence. Promoting insurance coverage is a common strategy for reducing cost-related unmet health needs, but public insurance programs and private insurance differ in the number and types of no-cost services provided, and groups with higher average poverty rates such as immigrants and racial and ethnic minorities may be more negatively impacted by healthcare costs. This study examined the relationship between insurance type and adolescents' cost-related unmet health needs overall and by race and ethnicity and whether parents are immigrants. METHODS: We used nationally representative cross-sectional data from the 2018-2021 Medical Expenditure Panel Survey Household Component. We conducted multivariable logistic regression analysis adjusting for other explanatory variables. We analyzed data for the full sample, by race and ethnicity, and by parents' immigrant designation (US-born, mixed immigrant type, and foreign-born). RESULTS: The sample included 11,493 adolescents aged 10-17 (weighted n = 32,320,725). In the overall analysis, adolescents with public insurance were less likely to have cost-related unmet health needs than those with private insurance. In the sub-sample analyses, this finding only was significant for adolescents with US-born parents and Non-Hispanic Black adolescents. CONCLUSIONS: These findings indicate that for some but not all groups of adolescents, public insurance is more beneficial than private insurance in terms of reducing cost-related unmet health needs. Additional research is needed to understand the reasons for these group-level differences and to develop strategies to ensure all adolescents have access to affordable health care.