Among the many factors contributing to the SES-achievement gap, executive function (EF) skills have received a considerable amount of attention, given their role in supporting academic skill development. While recent work has demonstrated that global EF constructs mediate SES-achievement relations, less attention has been paid to unpacking the role of specific EF components in linking SES to achievement. Data from the NICHD Study of Early Child Care and Youth Development (N = 1273) were analyzed to assess direct and indirect associations between SES indicators, preschool EF skills, and first-grade math and reading achievement. Using path analysis, we found parent education and working memory to be uniquely and most predictive of both achievement domains. Further, after controlling for baseline academic skills, verbal ability, and other child- and family-level covariates, only working memory mediated the association between parent education and children’s math achievement. These findings offer a comprehensive look at the specific mechanisms through which socioeconomic disadvantage contributes to children’s academic development and provide an initial step towards generating more precise targets for policies and interventions aimed at closing the achievement gap. (author abstract)