Shared living arrangements can provide housing, economies of scale, and other instrumental support and may become an important resource in times of economic constraint. But the extent to which such living arrangements experience continuity or rapid change in composition is unclear. Previous research on extended-family households tended to focus on factors that trigger the onset of coresidence, including life course events or changes in health status and related economic needs. Relying on longitudinal data from 9,932 households in the Survey of Income and Program Participation (SIPP), the analyses demonstrate that the distribution of economic resources in the household also influences the continuity of shared living arrangements. The results suggest that multigenerational households of parents and adult children experience greater continuity in composition when one individual or couple has a disproportionate share of the economic resources in the household. Other coresidential households, those shared by other kin or nonkin, experience greater continuity when resources are more evenly distributed.