This paper compares the identity-formation processes of Latino students in three different college contexts (a liberal arts college, a research university, and a regional public university). Drawing on ethnographic observations, in-depth interviews, and surveys of members of Latino student organizations, I chart the distinct ways in which Latino students interact with one another and arrive at particular ethnic identities on different campuses. By applying ethnoracialization theory to mesolevel settings, I examine how students respond to external ascription as they co-construct and negotiate their ethnic-racial understandings. I identify three different patterns by which students deploy panethnic boundaries, specifically, as they adopt and define identity labels: inclusive Latino identification signifying solidarity above all, qualified Latino identification mediated through specific organizational membership, and the rejection of panethnic identities. I consider how the organizational context of each campus provides a distinct racial climate that mediates student interactions and potentially shapes the disparate identity outcomes that result. The findings suggest that, beyond providing academic experiences, colleges also provide Latino students with disparate lessons regarding who they are and where they fit in the ethnoracial hierarchy.