Mathematics literacy is crucial in many STEM fields, yet Black and Hispanic students are less likely to achieve high math proficiency. While previous literature investigated potential factors to mitigate racial or gendered disparities in mathematics literacy, few studies attended to the conditions under which the causal interpretation of the results obtained can be established. Guided by intersectionality theory and causal decomposition analysis, we examined the degree to which disparities in mathematics literacy (a) exist at the intersection of race and gender and (b) can be reduced by hypothetical interventions that equalize school socioeconomic status (SES) or opportunity to learn (OTL) across groups. We found large racial/ethnic differences in math literacy favoring Asians and whites and much smaller gender differences. We also found that equalizing school SES may reduce disparities for Black and Hispanic males and females; equalizing OTL may reduce disparities for Black and Hispanic males as well as Asian males and females; compared to white males. Our findings suggest that interventions that target specific race–gender groups are required to reduce disparities in math literacy.