To make sound educational decisions, students and their parents have to be informed about the way the educational system works. Such knowledge, however, tends to vary across social groups. This study investigates the differences in education‐related knowledge between native and migrant mothers in the German context. Empirical analyses based on a sample of native German mothers and mothers from Turkey or the former Soviet Union (N = 2076) indicate that migrant mothers know less about the German educational system than their native counterparts. An investigation of the potential sources of these knowledge gaps shows that migrants’ weaker socio‐economic status explains a substantial part of their lower level of knowledge, particularly among families of Turkish origin. Furthermore, migrants’ less profitable social network composition and lower levels of German language skills contribute to their information deficits. Based on these empirical results, the study considers opportunities for improving the knowledge base of migrant parents.