The Westchester Medical Center says it cannot accept insurance purchased through the state health exchange in Westchester, Rockland and Putnam counties.
CEO Michael Israel says the reimbursements are too low to cover the costs of the services it offers as a teaching hospital.
The Journal News says patients and lawmakers are expressing outrage.
Westchester Medical Center used to be a public hospital. After years of red ink, it became a public benefit corporation 15 years ago.
It still uses public land and buildings, and its employees are part of the state pension system.
Montefiore, which has a teaching hospital in the Bronx, is accepting six out of the seven exchange plans available in Westchester County.
Memorial Sloan-Kettering Cancer Center is accepting two plans available in Westchester and Rockland.
(c) 2012 AP