We build on cross‐national research to examine the relationships underlying estimates of relative intergenerational mobility in the United States and Great Britain using harmonized longitudinal data and focusing on men. We examine several pathways by which parental status is related to offspring status, including education, labor market attachment, occupation, marital status, and health, and perform several sensitivity analyses to test the robustness of our results. We decompose differences between the two nations into that part attributable to the strength of the relationship between parental income and the child's characteristics and the labor market return to those child characteristics. We find that the relationships underlying these intergenerational linkages differ in systematic ways between the two nations. In the United States, primarily because of the higher returns to education and skills, the pathway through offspring education is relatively more important than it is in Great Britain; by contrast, in Great Britain the occupation pathway forms the primary channel of intergenerational persistence.