The Basic Rule: Age 65 or Older, or Disability or End-Stage Renal Disease

You can enroll in Medicare if you are 65 or older, or if you are under 65 and have been receiving Social Security disability benefits for 24 months, or if you have end-stage renal disease (ESRD) or amyotrophic lateral sclerosis (ALS). Most people fall into the first group. The age threshold is 65 for everyone — there is no variation by state or income.

If you are not yet 65, you do not automatically may have access to. Being unemployed, having a low income, or having a serious illness does not open Medicare to you unless you also meet one of the disability or disease conditions listed above. This is a common source of confusion: Medicare is not a poverty program or a general health insurance program for people under 65.

Key Takeaways

  • You must be 65 or older, or under 65 and receiving Social Security disability benefits for at least 24 months, or have end-stage renal disease or ALS.
  • You must be a U.S. citizen or a lawful permanent resident who has lived in the United States for at least five consecutive years.
  • You do not need a work history of your own if you are 65 or older and your spouse or ex-spouse has the required work history.
  • If you miss your initial enrollment window, you may face a permanent penalty on your premiums, so the timing of when you sign up matters.
  • People under 65 with disability must have been receiving benefits for exactly 24 months before Medicare begins, not before they explore.

Work History Requirements: Yours or Your Spouse's

To enroll in Medicare Part A (hospital insurance), you or your spouse must have worked and paid Medicare taxes for at least 40 quarters — roughly 10 years. The work does not have to be recent. If you worked 10 years at any point in your life and paid into the system, you meet this requirement.

You do not need to have worked yourself. If you are 65 or older and your current spouse, ex-spouse, or deceased spouse has 40 quarters of work history, you can enroll based on their record. The same applies if you are under 65 and receiving disability benefits — the work history can belong to your spouse or parent.

If neither you nor your spouse has 40 quarters, you cannot enroll in Medicare Part A at no cost. You may be able to purchase it, but the monthly premium will be higher than for people who have the work history. Contact Social Security to review your specific work record and determine whether you have enough quarters.

Citizenship and Residency: What the Law Requires

You must be a U.S. citizen or a lawful permanent resident. Lawful permanent residents are people with a green card. If you are neither, you cannot enroll in Medicare, regardless of age or work history.

If you are a lawful permanent resident, you must have lived in the United States for at least five consecutive years before you can enroll. Those five years do not have to be when ready before you turn 65 — they can be at any point in your life. However, they must be consecutive; a break in residency restarts the clock.

Citizenship is verified through Social Security when you explore. If you are a permanent resident, bring your green card or other proof of status. If there is any question about your residency timeline, Social Security will ask for documentation of when you entered the country and whether you left and returned.

Disability Before Age 65: The 24-Month Waiting Period

If you are under 65 and receiving Social Security Disability Insurance (SSDI) or Supplemental Security Income (SSI) based on disability, you become may be able to access for Medicare after you have been receiving benefits for 24 months. The 24 months is measured from the month your benefits began, not from the month you applied.

This means if your disability benefits started in January, you become may be able to access for Medicare in January of the following year, two years later. You do not have to do anything to trigger this — Medicare enrollment happens automatically. However, you should verify that you are enrolled by checking your Social Security account or calling Social Security to confirm.

If you are receiving SSI (Supplemental Security Income) rather than SSDI, the same 24-month rule applies. The difference between the two programs does not affect Medicare may be able to access.

End-Stage Renal Disease and ALS: when ready may be able to access

If you have end-stage renal disease (ESRD) — kidney failure requiring dialysis or a transplant — you can enroll in Medicare when ready, regardless of age. You do not have to wait until 65 or meet any work history requirement. The same applies if you have been diagnosed with amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease.

For ESRD, Medicare coverage typically begins the first day of the month in which your dialysis treatments begin, or the month of your kidney transplant. You will need documentation from your nephrologist or dialysis center confirming your diagnosis and treatment start date.

For ALS, Medicare begins the first day of the month after you are approved for Social Security disability benefits based on your ALS diagnosis. You do not have to wait the usual 24 months that other disability beneficiaries must wait.

Enrollment Timing and Penalties for Missing important date

Your initial enrollment period is the seven-month window that includes the three months before the month you turn 65, the month you turn 65, and the three months after. If you enroll during this window, your coverage begins the month you turn 65 (or the first day of that month).

If you miss this window and do not have employer coverage or other may have access to circumstances, you will face a permanent penalty on your Part B and Part D premiums. The penalty is 10 percent per year of delay for Part B and 1 percent per month of delay for Part D. These penalties stay with you for life, even after you eventually enroll.

There are exceptions: if you or your spouse are still working and covered by an employer plan, you may have a special enrollment period that lets you enroll without penalty. If you think you may have access to for an exception, contact Medicare or Social Security before your initial enrollment period ends.

Frequently Asked Questions

Can I enroll in Medicare if I am not a U.S. citizen?

You must be a U.S. citizen or a lawful permanent resident with at least five consecutive years of U.S. residency. If you are neither, you cannot enroll. If you are working toward citizenship or permanent residency, contact Social Security to learn what documentation you will need when you do become may be able to access.

What if I worked outside the United States?

Work performed outside the U.S. generally does not count toward the 40 quarters required for Medicare Part A, even if you paid into a similar system in another country. However, some countries have agreements with the U.S. that allow certain work to count. Contact Social Security to review your specific work history.

Can I get Medicare based on my parent's work history?

Yes, if you are under 65 and receiving Social Security disability benefits. Your parent's work history can be used to establish your may be able to access. If you are 65 or older, you cannot use a parent's work history; only a spouse's or ex-spouse's record works.

Do I lose Medicare if I move out of the United States?

If you are a U.S. citizen, you keep Medicare even if you move abroad. If you are a permanent resident, you may lose may be able to access if you leave the country for an extended period. Contact Medicare before you move to understand how your coverage will work outside the U.S.

What happens if I was denied disability benefits but I am still very ill?

If Social Security denied your disability claim, you do not may have access to for Medicare under the disability pathway, even if you believe you should have been approved. You can request reconsideration or appeal the decision through Social Security. Until then, you would need to explore other insurance options like the Affordable Care Act marketplace.