The Basic Age and Citizenship Rules for Medicare

You can enroll in Medicare when you turn 65, regardless of your work history or income — that is the main threshold. You must also be a U.S. citizen or a permanent resident who has lived in the country for at least five consecutive years. If you meet both conditions, you become may be able to access to sign up during your enrollment period, which typically opens three months before the month you turn 65.

The 65-year-old rule applies to most people, but there are exceptions. If you have been receiving Social Security Disability Insurance (SSDI) for 24 months, you can enroll in Medicare before 65. If you have end-stage renal disease (ESRD) or amyotrophic lateral sclerosis (ALS), you may be able to enroll at any age. These are the only circumstances under which age 65 is not the requirement.

Key Takeaways

  • You become may be able to access for Medicare at age 65 if you are a U.S. citizen or permanent resident who has lived in the country for at least five consecutive years.
  • You can enroll starting three months before the month you turn 65, and you have a window of seven months to sign up without a penalty.
  • If you have received SSDI for 24 months, you can enroll in Medicare before age 65.
  • Missing your initial enrollment window can result in a permanent penalty added to your Part B and Part D premiums.
  • You do not need to stop working to enroll in Medicare, and your enrollment does not depend on your income or savings.

How the Enrollment Window Works

Your Initial Enrollment Period is a seven-month window that begins three months before the month you turn 65 and ends three months after. For example, if you turn 65 in June, your window opens in March and closes in September. You can enroll during any of those seven months, and coverage will start on the first day of the month you turn 65 (or the first of the following month if you enroll after your birthday month).

If you miss this window, you can still enroll later, but you will face a late enrollment penalty. This penalty is permanent — it stays on your Part B and Part D premiums for as long as you have Medicare. The penalty for Part B is 10 percent of the standard premium for each full year you were may be able to access but did not enroll. The Part D penalty is 1 percent of the national average premium for each month you were without creditable coverage. These amounts are recalculated each year, so the penalty grows over time.

Special Circumstances That Change the Age Requirement

If you are receiving SSDI, you become may be able to access for Medicare after you have been on disability for 24 months. The 24 months are counted from the date your disability benefit began, not from when you first applied. Once you reach 24 months of SSDI, you will be automatically enrolled in Medicare Part A and Part B — you do not need to take any action. This automatic enrollment happens in the month you reach the 24-month mark.

If you have end-stage renal disease (ESRD), you can enroll in Medicare regardless of age. ESRD means your kidneys function at less than 15 percent of normal capacity, or you need dialysis or a transplant. You become may be able to access the month your kidney disease is diagnosed, or the month dialysis or a transplant begins, whichever comes first. If you have ALS (Lou Gehrig's disease), you become may be able to access for Medicare the month your ALS is diagnosed, with no age requirement at all.

What Happens If You Are Still Working at 65

You do not have to stop working to enroll in Medicare. If you are still employed and covered by your employer's health plan, you may be able to delay enrolling in Part B without facing a late enrollment penalty. This is called creditable coverage — if your employer plan is as good as or better than Medicare Part B, you can stay on it and enroll in Medicare later without penalty.

However, you should still enroll in Part A at 65, even if you are working. Part A is hospital insurance and is usually free if you or your spouse paid Medicare taxes for at least 10 years. Delaying Part A enrollment can result in a permanent penalty if you do not have creditable coverage through your employer. If you are unsure whether your employer plan counts as creditable coverage, contact your employer's benefits office or call Medicare at 1-800-MEDICARE to ask.

Enrollment for Spouses and Family Members

Your spouse becomes may be able to access for Medicare at 65 based on their own age, citizenship, and residency — not based on your enrollment. If your spouse is not yet 65 but you are, they cannot enroll in your Medicare plan. They will have their own enrollment period when they turn 65.

Adult children and other family members do not become may be able to access for Medicare based on your enrollment either. Medicare is not a family plan. Each person must meet the age requirement (or the SSDI/ESRD/ALS exception) on their own. If a family member is under 65 and does not may have access to under the disability or disease exceptions, they will need to explore other coverage options until they reach 65.

How to Confirm Your may be able to access Status

You can check your may be able to access by creating an account on Medicare.gov and logging into "My Medicare." This tool shows your current coverage status and tells you when your enrollment period begins. You can also call Social Security at 1-800-772-1213 to confirm your may be able to access based on your work record, or call Medicare directly at 1-800-MEDICARE to ask about your specific situation.

If you are receiving SSDI, Social Security will notify you when you reach 24 months and are may be able to access for Medicare. You do not need to contact them — the notification will arrive by mail. If you have ESRD or ALS, your doctor or dialysis center can help you understand your enrollment options and timeline.

Penalties for Missing Your Enrollment Window

The late enrollment penalty for Part B is calculated as 10 percent of the standard Part B premium for each 12-month period you were may be able to access but did not enroll. If the standard premium is $165 per month and you miss two years, your penalty would be 20 percent of that amount, added to your premium permanently. Part D penalties work similarly but are calculated monthly at 1 percent of the national average premium.

These penalties do not go away. Even if you enroll years later, the penalty remains part of your premium for life. The only exception is if you had creditable coverage (such as an employer plan or retiree coverage) during the time you were not enrolled in Medicare. If you can prove you had creditable coverage, you may be able to avoid the penalty. Keep documentation of any health coverage you had during the gap.

Frequently Asked Questions

Can I enroll in Medicare before I turn 65 if I am still working?

No, unless you have been receiving SSDI for 24 months, or you have ESRD or ALS. If you are still working and covered by an employer plan, you can delay Part B enrollment without penalty, but you should still enroll in Part A at 65 to avoid a permanent penalty on Part A premiums.

What if I miss my enrollment window by a few months?

You can still enroll, but you will owe a late enrollment penalty on Part B and Part D premiums. The penalty is permanent and increases the longer you wait. Enroll as soon as you realize you missed the window to minimize the total penalty amount.

Do I need to be a U.S. citizen to enroll in Medicare?

You must be a U.S. citizen or a permanent resident who has lived in the country for at least five consecutive years. If you are a permanent resident, you will need to provide proof of your status when you enroll.

If I am on disability and turn 65, do I need to do anything?

No. When you reach 24 months of SSDI, you are automatically enrolled in Medicare Part A and Part B. You will receive a notice in the mail, but you do not need to take action. Your coverage will begin the month you reach the 24-month mark.

Can my adult child enroll in Medicare with me?

No. Medicare is not a family plan. Your adult child must meet the age requirement (65) or one of the disability or disease exceptions on their own. They will have their own enrollment period when they turn 65.