[영문]Medicare and Social Security often are assumed to provide universal coverage for the population age 65 and older. Evidence from New York City raises doubts. Data from the Statewide Planning and Research Cooperative System, the Centers for Medicare and Medicaid Services, the Social Security Administration, and the U.S. Bureau of the Census provide evidence that 16% to 20% of New York City residents age 65 and older lack such coverage. Noncoverage is not unique to this city, but it may be particularly common there. Noncoverage is pronounced in, but not limited to, certain immigrant groups. Because the population share covered by Medicare increases with age and most hospitalizations not covered by Medicare are paid by Medicaid, Medicaid gradually may be replacing Medicare as the payer for hospitalizations for a substantial share of the 65+ population in New York City.