Objectives: We evaluated the relationship between ageism and social networks as well as ageism and thwarted belonging using the framework of the relational ageism theory among a sample of older adults in the United States. Method: Volunteers 65 and older were recruited to participate in a survey through Research Match. Demographics, social network, thwarted belongingness, and ageism were examined. Data were analyzed using hierarchical logistic regression analysis. Results: 454 individuals from more than 30 states participated in the current study. Study results demonstrated that internalized and relational ageism significantly predicted thwarted belonging and social network. Conclusion: Findings present pathways for understanding associations between ageism and social networks as well as ageism and thwarted belonging. This study has important implications for the development of social risk factors associated with high levels of ageism.