En español | Nobody is automatically entitled to Medicare. To qualify you must meet certain requirements.

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You qualify at age 65 or older if:

• You are a U.S. citizen or a permanent legal resident; and
  

• You or your spouse has worked long enough to be eligible for Social Security or railroad retirement benefits — usually having earned 40 credits from about 10 years of work — even if you are not yet receiving these benefits; or
  

• You or your spouse is a government employee or retiree who has not paid into Social Security but has paid Medicare payroll taxes while working.
  

Note: You can qualify for Medicare on your spouse's work record if he or she is at least age 62 and you are at least age 65. You also may qualify on the work record of a divorced or deceased spouse. But under the Defense of Marriage Act, people in same-sex marriages cannot qualify on their spouse's work record.

You qualify under age 65 if:

• You have been entitled to Social Security disability benefits for at least 24 months (which need not be consecutive); or
  

• You receive a disability pension from the Railroad Retirement Board and meet certain conditions; or
  

• You have Lou Gehrig's disease (amyotrophic lateral sclerosis), which qualifies you immediately; or
  

• You have permanent kidney failure requiring regular dialysis or a kidney transplant — and you or your spouse has paid Social Security taxes for a certain length of time, depending on your age.
  

If you do not qualify on your own or your spouse's work record

Provided that you're a U.S. citizen or have been a legal resident for at least five years, you can still get Medicare benefits at age 65 or older by:

• Paying premiums for Part A (hospital insurance). If you have fewer than 30 work credits, you pay the maximum premium, $441 a month in 2013. If you have 30 to 39 credits, you pay less, $243 a month in 2013. If you continue working until you gain 40 credits, you will no longer pay these premiums.
  

• Paying the same monthly premiums for Part B, which covers doctor visits and other outpatient services, as other enrollees pay.
  

• Paying the same monthly premium for Part D prescription drug coverage as others enrolled in the drug plan you choose.
  

You can enroll in Part B without Part A. But if you buy into A, you also must enroll in B. You can get Part D if you're enrolled in either A or B.

Most people receive annual statements from Social Security saying whether they're yet eligible on their work records. If you don't get these statements, or are still not sure if you qualify, call Social Security at 1-800-772-1213.

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