BackgroundThis study aimed to examine the differences in relationships among social capital components, health status, sociodemographic characteristics, and subjective well-being (SWB) among older adults in institutionalized versus non-institutionalized care environments.MethodsA cross-sectional survey was conducted involving 1,037 older adults aged 65-95 years from nine communities and nine nursing homes across three regions of Zhejiang Province, China. Social capital and SWB were assessed using the Social Capital Scale and the Memorial University of Newfoundland Scale of Happiness (MUNSH), respectively. Propensity score matching (PSM, 1:1, caliper width 0.02) was applied to balance key sociodemographic characteristics and health status between community-dwelling and nursing home residents. Multivariable linear regression was utilized to analyze the relationships among social capital components, health status, sociodemographic factors, and SWB in both groups.ResultsPSM identified 290 older adults in community dwellings and a comparable group (n = 290) in nursing homes. Comparative analysis showed that nursing home residents demonstrated lower SWB. Multivariable linear regression revealed that social connection, trust, and cohesion were positively associated with SWB in both groups. However, social participation was only significantly linked with community dwellings residents. Both groups showed a positive relationship between SWB and self-rated health, but the number of chronic conditions did not show a significant link with SWB. Additionally, higher income (>= 3000 RMB) and a middle school education linked to higher SWB among community-dwelling older adults, whereas family structure, specifically being not in union and having three or more children, was associated with lower SWB in the nursing home group.ConclusionSocial capital and health status showed a strong and consistent association with SWB in both groups. Strengthening social connections, trust, and cohesion, along with maintaining positive health perceptions, is expected to enhance the well-being of older adults, particularly for those in institutional settings. Notably, differences in how sociodemographic factors influence SWB across settings. These findings indicate the necessity for tailored interventions that address the unique needs of each care environment to promote healthier aging experiences.