- Cedarcrest Hospital (psychiatric) – Newington
- Elmcrest Hospital (psychiatric) – Portland (Saint Francis Hospital and later Hartford Hospital operated psychiatric facilities at the campus following Elmcrest's closure; the site was vacant as of 2014.)
- Hospital of Saint Raphael – New Haven (incorporated into Yale New Haven Hospital as the Saint Raphael Campus)
- Knight Hospital (psychiatric) – Mansfield (closed in 1993, now part of the Depot Campus of the University of Connecticut
- Newington Children's Hospital – Newington (relocated to Hartford as Connecticut Children's Medical Center)
- Norwich State Hospital (psychiatric) – Preston
- Park City Hospital (Bridgeport) – Bridgeport
- Seaside Regional Center (psychiatric) – Waterford
- St. Joseph's Medical Center (Stamford) – Stamford (after the hospital building was torn down, the Tully Medical Center of Stamford Hospital was built on the same site)
- Uncas on Thames Hospital – Norwich (state-owned tuberculous and specialty hospital)
- Winsted Memorial Hospital – Winsted – Emergency department service provided at the site by Charlotte Hungerford Hospital
- "Membership Listing". Connecticut Hospital Association.
- "Connecticut Hospitals". American Hospital Directory. Retrieved April 30, 2020.
- "Uncas-on-thames Hospital Closing, A Victim Of Medicine's Changing Face". The Hartford Courant. 3 January 1995. Retrieved 16 September 2018.