Despite widespread support for democracy among citizens in Latin America, rising polarization over recent decades raises questions about whether such dynamics erode pluralist norms among ordinary citizens. While recent scholarship argues that polarization in the region is largely elite-driven it remains unclear whether, and under what conditions, this polarization diffuses to the mass public and undermines citizens’ commitment to core democratic principles, including minority rights. This paper addresses this gap by examining the relationship between ideological extremism, mass polarization, and social intolerance in Latin America. I argue that citizens who locate themselves at the ideological extremes are more likely to reject outgroups as neighbors and to tolerate violations of minority rights. Crucially, I propose that country-level ideological polarization conditions this relationship: in more polarized contexts, politics becomes increasingly organized around group boundaries, amplifying the exclusionary tendencies of ideological extremism. Drawing on Latinobarómetro survey data across seventeen countries, we exploit both individual-level variation in ideological self-placement and country-level variation in ideological polarization to assess how extremism and polarization jointly shape attitudes toward ethnic minorities, immigrants, sexual minorities, and religious dissenters. Using multilevel models, the results show that ideological extremism is a strong predictor of social intolerance, and that this effect is significantly stronger in highly polarized environments. The case of Venezuela, where approximately one-third of respondents self-identify at the far right of the scale, serves as a critical case illustrating how extreme mass ideologies, embedded in a deeply polarized political environment, can translate into widespread intolerance even under conditions of democratic deterioration. These findings contribute to debates on democratic backsliding by demonstrating that polarization is not only an elite strategy but also a mass-level process with normative consequences. When extremism and polarization converge, citizens become more tolerant of violations of minority rights, thereby lowering the social and political costs of democratic erosion.