Yes, NYSHIP requires retirees to enroll in Medicare Parts A and B once they are retired and eligible for Medicare. Medicare becomes your primary insurance (Medicare pays first) at that point. Your covered dependents must also enroll when eligible (i.e., they turn age 65). NYSHIP will not provide any benefits for coverage available under Medicare if you or a dependent are eligible for Medicare coverage that is primary but fails to enroll when eligible. You will then be responsible for the full cost of services that Medicare would have covered.