Background On December 20, 2019, the minimum age for purchasing tobacco in the US was raised nationally to 21 years. We evaluated this law (Tobacco 21 [T21]) 1 year after implementation. We also compared states with versus without T21 policies during 2019 to explore potential equity impacts of T21 policies. Methods We examined shifts in tobacco access among 6th through 12th graders using the National Youth Tobacco Survey. To explore equity of state T21 policies among youths and young adults, the associations with tobacco use were explored separately for race and ethnicity by using data from the 2019 Behavioral Risk Factor Surveillance System (for persons aged 18 to 20 years) and the 2019 Youth Risk Behavior Survey (for high school students). Results The overall percentage of 6th to 12th graders perceiving that it was easy to buy tobacco products from a store decreased from 2019 (67.2%) to 2020 (58.9%). However, only 17.0% of students who attempted buying cigarettes in 2020 were unsuccessful because of their age. In the 2019 BRFSS, those aged 18 to 20 years living in a state with T21 policies had a lower likelihood of being a current cigarette smoker (adjusted prevalence ratio [APR], 0.58) or smoking cigarettes daily (APR, 0.41). Similar significant associations were seen when analyses were restricted to only non-Hispanic White participants but not for participants who were non-Hispanic Black, non-Hispanic Asian, Hispanic, or of other races or ethnicities. Consistent findings were seen among high school students. Conclusion Greater compliance with the federal T21 law is needed as most youth who attempted buying cigarettes in 2020 were successful. Comparative analysis of states with versus states without statewide T21 policies in 2019 suggest the policies were differentially more protective of non-Hispanic White participants than other participants. Equitable and intensified enforcement of T21 policies can benefit public health.