Background: Deinstitutionalization research shows better services and outcomes relative to institutional life but has not compared formerly institutionalised and never-institutionalised service users. Methods: We used propensity score matching (PSM) to match formerly institutionalised and never-institutionalised participants on six personal characteristics. Data came from the 2018 to 2019 National Core Indicators In-Person Survey. We excluded current institution residents, and states with 25% + of missing data on former institutionalisation. Results: Overall, 15.5% of participants in the 29-state full sample had lived in an institution for 1 year or more. Findings from the PSM sample showed that former-institution residents were more likely to use congregate living arrangements and less likely to live with family. They experienced more loneliness, less support-related choice, and had a consistent pattern of disability service-focused social connections. Conclusions: Many former institution residents remain disadvantaged relative to matched peers. There is a need to identify factors to enhance services and outcomes following deinstitutionalization.