When is membership in a social category considered a legitimate basis for treating peopledifferently? We compared two dimensions of social categorization that are central to debatesabout inequality and differential treatment: social class and race/ethnicity. In Study 1 (N =677 Swiss and U.S. students), participants evaluated a teacher who admitted vs. excluded aborderline student from an advanced track because of his working-class vs. racial/ethnicminority background. Differential treatment based on social class was judged more acceptablethan differential treatment based on race/ethnicity, regardless of whether it benefited orharmed the student. Open-ended responses suggested that social class elicited reasoning aboutunequal opportunities, whereas race/ethnicity elicited concerns about discrimination. Study 2(N = 2,777 U.S. adults) was consistent with these explanations: Social class disparities inresources were perceived as larger, but racial categories were perceived as more entitative andmeaningful. Study 3 (General Social Survey, 1975–2024) extended the asymmetry betweensocial class and race to attitudes about government assistance: Americans saw class-relatedfactors as more important than race for getting ahead in life and were correspondingly moresupportive of government assistance targeting poor than Black people. Taken together, thesefindings suggest that social class is a more permissible basis for differential treatment thanrace/ethnicity, an asymmetry that tracks how the two categories are perceived: race/ethnicityas a more coherent identity, and social class as a marker of individuals’ circumstances andopportunities.