Up to now, we know only a little about the causal effect of international migration on partnership stability, with the few existing analyses being restricted to internal migration or international migration from less developed countries to the Global North. Using longitudinal data on German citizens [the German Emigration and Remigration Panel Study plus the German Family Panel (pairfam)], this study contributes to existing literature primarily in two ways: first, by comparing international migrants to nonmigrants at origin and applying the appropriate methods (Entropy Balancing and Discrete Time Proportional Hazards Models), the causal effect of international migration was studied. Second, assessing (non-)mobile German citizens allows looking at these effects in the context of a highly industrialized welfare state. Additional to the general effect of international migration, differences between emigrants and remigrants are studiedwhich has not been done before, except for the Latin American context. To advance our understanding of the underlying mechanisms, the role of further migration characteristics is investigated. Findings show that international migration increases the risk of union dissolution compared to no migration and that the risk of union dissolution is higher for remigrants compared to emigrants. The underlying migration reasons play an additional role in explaining the risk of union dissolution.