Medicare starts at age 65 for most people, but you can enroll earlier if you have a disability, end-stage renal disease, or ALS

You become may be able to access for Medicare the month you turn 65, regardless of whether you are still working. If you were born on the first of the month, your coverage begins the month before. The enrollment window opens three months before the month you turn 65 and closes three months after — a seven-month window total. Missing this window can mean a permanent penalty on your premiums, so the timing matters.

You do not have to be retired to enroll. You do not have to stop working. You enroll through Social Security, either online at ssa.gov, by phone at 1-800-772-1213, or in person at your local Social Security office. The process itself takes about 15 minutes if you have your Social Security number and birth certificate information ready.

Key Takeaways

  • You can enroll in Medicare starting three months before you turn 65, and you have until three months after your birthday to sign up without a penalty.
  • If you are already receiving Social Security benefits, you are enrolled automatically in Medicare Part A and Part B when you turn 65.
  • You can enroll earlier than 65 if you have been receiving Social Security disability benefits for 24 months, have end-stage renal disease, or have been diagnosed with ALS.
  • Enrolling late outside your window can result in a permanent 10 percent increase to your Part B premium for each year you delayed.

Automatic enrollment if you receive Social Security

If you are already collecting Social Security retirement or disability benefits when you turn 65, Medicare enrolls you automatically. You will receive your Medicare card in the mail about two weeks before your 65th birthday. You do not need to do anything — the enrollment happens on its own.

This automatic enrollment covers Part A (hospital insurance) and Part B (medical insurance). You will still need to decide whether to add Part D (prescription drug coverage) or a Medigap or Medicare Advantage plan, but the basic coverage starts without action on your part.

Enrolling yourself if you are not yet on Social Security

If you have not started collecting Social Security benefits, you must enroll in Medicare yourself. You can do this online at ssa.gov by creating a my Social Security account, or you can call Social Security directly. The online process is fastest — you answer questions about your income, citizenship, and work history, and the system tells you what parts of Medicare you are may be able to access for.

You will need your Social Security number, birth certificate or passport, and proof of citizenship (a passport, naturalization papers, or a birth certificate issued in the United States). If you are enrolling by phone, have these documents nearby but you do not need to mail them unless Social Security specifically asks.

Earlier enrollment: disability, end-stage renal disease, or ALS

You can enroll in Medicare before 65 if you have been receiving Social Security disability benefits (SSDI) for 24 months. The 24 months does not have to be consecutive — it counts from the first month you received a disability payment. Once you hit 24 months, you become may be able to access for Medicare automatically, and coverage begins the month after you reach that milestone.

You are also may be able to access at any age if you have been diagnosed with end-stage renal disease (ESRD) — permanent kidney failure requiring dialysis or a transplant. Enrollment is automatic once your doctor certifies the diagnosis to Social Security. Similarly, if you have been diagnosed with amyotrophic lateral sclerosis (ALS), you become may be able to access for Medicare when ready, without any waiting period.

What happens if you miss your enrollment window

If you turn 65 and do not enroll during your seven-month window, you can still enroll later, but you will face a late enrollment penalty. For Part B, the penalty is 10 percent of the standard premium for each full year you delayed. If the standard Part B premium is $165 per month and you delayed for three years, your premium becomes $215 per month for life — the penalty does not go away.

The same penalty applies to Part D (prescription drug coverage). If you go 63 days or more without creditable drug coverage, you pay an extra amount each month you are enrolled in Part D. The only exceptions are if you had other health coverage that was at least as good as Medicare, or if you may have access to for a Special Enrollment Period due to a life event like losing employer coverage.

Special Enrollment Periods and life changes

A Special Enrollment Period lets you enroll outside your normal window if you experience certain life events. Losing employer health coverage, moving out of your plan's service area, getting married, or having a significant change in income all may have access to. You have 63 days from the event to enroll without penalty.

If you are still working and covered by your employer's health plan, you can delay Part B enrollment without penalty as long as you are actively employed and covered by that plan. Once you or your spouse stops working, you have eight months to enroll in Part B without a late penalty. This is one of the few situations where delaying does not cost you.

Enrollment for non-citizens and people with limited work history

You must be a U.S. citizen or a lawful permanent resident (green card holder) to enroll in Medicare. If you are a lawful permanent resident, you must have held that status for at least five years. Undocumented immigrants are not may be able to access for Medicare, regardless of age or work history.

You do not need a specific number of work years to enroll at 65 — you are may be able to access straightforward by reaching that age and meeting citizenship requirements. However, if you want Part A (hospital insurance) without paying a premium, you or your spouse must have worked and paid Medicare taxes for at least 40 quarters (10 years). If you have fewer than 40 quarters, you can still enroll in Part A but will pay a monthly premium.

Frequently Asked Questions

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

Yes, if you are may be able to access through disability, ESRD, or ALS, you can enroll regardless of work status. If you are turning 65 and still employed, you can enroll during your normal window without any penalty, even if you keep working. You do not have to retire to sign up for Medicare.

What if I was born on the first of the month?

Your Medicare coverage begins the month before you turn 65. Your enrollment window still opens three months before that earlier month. For example, if you were born January 1, your coverage starts in December, and your enrollment window opens in September.

Do I have to choose a plan when I first enroll?

You must enroll in Part A and Part B, but choosing a Medigap or Medicare Advantage plan is optional. If you do not choose a plan during your initial enrollment, you are in Original Medicare (Part A and Part B). You can add a plan later during the Annual Enrollment Period (October 15 to December 7 each year), though waiting may cost you more.

What if I missed my enrollment window years ago?

You can still enroll, but you will owe the late penalty on Part B and Part D for every year you delayed. The penalty is permanent — it does not expire. Contact Social Security to enroll now and discuss your penalty amount with them.

Does my spouse's work history count toward my Part A coverage?

Yes. If you do not have 40 quarters of your own work history, you may be able to use your spouse's work record to may have access to for premium-free Part A. Your spouse must be at least 62 years old (or deceased) for you to use their record. Ask Social Security to check both records when you enroll.