Does Rural–Urban Mobility Improve the Well-Being of Rural Older Adults? Evidence from Changing Living Arrangements in China

Population ageing and rural–urban transformation are reshaping the living arrangements of older adults in China, with important implications for health equity, later-life well-being, and the social sustainability of rural–urban development. Using the China Longitudinal Aging Social Survey (CLASS), this study examines how changing living arrangements affect the multidimensional well-being of rural older adults. Four living arrangements—rural–urban mobility co-residence, left-behind living, urban co-residence with children, and rural co-residence with children—are identified, and a double machine learning approach is employed to address nonlinearities and high-dimensional confounding. The results show that, compared with left-behind living, rural–urban mobility co-residence significantly improves the well-being of rural older adults. However, this mobility dividend is accompanied by multidimensional trade-offs: it improves mental health, living conditions, and health behaviors while negatively affecting physical health, social participation, and economic security. Rural co-residence also generates significant well-being gains, suggesting that relocation to urban areas is not the only pathway to improving later-life well-being. Moreover, the benefits of rural–urban mobility co-residence vary substantially with family characteristics, particularly children’s gender composition and educational attainment. Mechanism analyses further reveal a dual effect of mobility: it enhances well-being by strengthening intergenerational support and facilitating self-development, but may simultaneously increase intergenerational contribution and weaken social identification. These findings highlight the importance of social integration of mobile older adults, local elderly-care services, and family support in reducing inequalities in later-life well-being among mobile older adults.