Ethnic and racial minorities in many countries experience worse relative health outcomes and earlier mortality compared to national averages or outcomes of the majority population. Although socioeconomic status often contributes to a portion of ethno-racial health disparities, there are many unanswered questions about the relationship between socioeconomic status and ethno-racial health disparities across contexts. Recent scholarship in the USA has found support for a “diminished returns” effect in which the socioeconomic health gradient is systematically smaller for marginalized groups, yet it is unclear whether this pattern exists in other national contexts. This study tests the interaction between socioeconomic status and ethno-racial minority status in 30 countries across six waves of the European Social Survey. The results include evidence of the diminished returns pattern, particularly for populations with origins in Sub-Saharan Africa and the Middle East. Multilevel mixed-effects models find variation across countries in the interaction between socioeconomic status and ethno-racial minority status. The findings suggest racism and socioeconomic status interact to affect health and health disparities in multiple contexts and highlight the importance of cross-national comparison to further understand variation across countries.