The Shifting Nature of Intergenerational Coresidence in South Korea: 1975-2020

South Korea has undergone profound family transformations over the past five decades, marked by delayed marriage, rapid fertility decline, and rising divorce amid compressed socioeconomic change. Despite extensive scholarship on demographic trends, much less is known about how intergenerational living arrangements have evolved in this context. Using 1% microdata from the Korean censuses (1975–2020), this study examines changes in intergenerational coresidence from both the children’s and parents’ perspective, distinguishing patterns by marital status and exploring variations by age, gender, and educational attainment. We further apply decomposition techniques to disentangle behavioral and compositional contributions to overall trends. Results reveal a shifting nature of intergenerational coresidence: the traditional pattern of married children living with parents has nearly disappeared, driven by both behavioral and compositional changes, while the growing share of unmarried adults has given rise to “two-adult-generation” households. Korea thus exemplifies both transformation and continuity in intergenerational living. These findings call for a reconceptualization of intergenerational coresidence amid Korea’s rapid demographic and social transformation.