You usually enroll in Medicare Part A automatically, but you may need to take action depending on your work history

Most people do not need to submit an process for Medicare Part A. If you are receiving Social Security benefits when you turn 65, Medicare Part A enrollment happens automatically — you will receive your Medicare card in the mail about three months before your 65th birthday. However, if you are still working and have not yet claimed Social Security, or if you have a non-work visa status, you will need to enroll yourself through Social Security.

The key difference is whether Social Security already has your information on file. If it does, the system connects automatically. If it does not, you must contact Social Security directly to start the process. Waiting past your initial enrollment window can result in permanent penalties on your Part A premiums, even if you eventually enroll.

Key Takeaways

  • If you receive Social Security benefits before age 65, Medicare Part A enrollment is automatic and requires no action on your part.
  • If you are still working and have not claimed Social Security, you must enroll in Medicare Part A yourself through Social Security before or at age 65.
  • Your initial enrollment window is the three months before your 65th birthday, the month you turn 65, and the three months after — a total of seven months.
  • Missing your enrollment window can add a 10 percent permanent surcharge to your Part A premiums for twice as long as you delayed enrollment.
  • You can enroll online at ssa.gov, by phone at 1-800-772-1213, or in person at your local Social Security office.

When you are automatically enrolled in Part A

Social Security automatically enrolls you in Medicare Part A and Part B if you are already receiving Social Security retirement, disability, or survivor benefits when you turn 65. This is the most common path. You do not need to do anything — Social Security sends your Medicare card to your address on file, typically arriving three months before your 65th birthday.

If you are receiving benefits from the Railroad Retirement Board instead of Social Security, the Railroad Retirement Board handles your Medicare enrollment the same way. You will still receive your card automatically, and the process works identically.

When you must enroll yourself in Part A

You need to contact Social Security yourself if you are age 65 or older and have never received Social Security retirement or disability benefits. This includes people who are still working, people who delayed claiming benefits, and people who are not yet may be able to access for Social Security because they do not have enough work credits.

You also must enroll yourself if you have a non-work visa (such as an H-1B visa) and are turning 65. Visa holders can enroll in Medicare Part A at 65 even if they are not yet citizens or permanent residents, but Social Security does not enroll them automatically. You will need to provide your visa documentation when you contact Social Security.

If you are a federal employee or railroad worker with a pension but no Social Security record, contact your employer's benefits office first — they may handle Medicare enrollment differently than Social Security does.

Your enrollment window and what happens if you miss it

Your initial enrollment period runs for seven months: the three months before you turn 65, the month of your birthday, and the three months after. If you miss this window, you can still enroll, but you will face a permanent penalty.

The penalty is a 10 percent increase to your Part A premium for each full year you delayed enrollment after your initial period ended. The surcharge lasts for twice as long as you were late. For example, if you enroll three years after your initial period ended, you pay 30 percent more per month for six years. This penalty does not go away — it stays on your premiums for life.

The only exception is if you had creditable health coverage (such as employer insurance) during the time you were not enrolled in Medicare. If you can show that you had continuous coverage, you may avoid the penalty. You will need to provide proof of that coverage when you enroll.

How to enroll online, by phone, or in person

The fastest way to enroll is online at ssa.gov/benefits/retirement/. You will need to create a my Social Security account if you do not already have one. The online process takes about 15 minutes and you can complete it any time of day. You will receive a confirmation number when ready.

If you prefer to speak with someone, call Social Security at 1-800-772-1213. Representatives are available Monday through Friday, 7 a.m. to 7 p.m. your local time. Wait times are typically shorter early in the morning or late in the afternoon. Have your Social Security number, birth date, and citizenship status ready.

You can also visit your local Social Security office in person. Find the office nearest you at ssa.gov/locator. Bring your Social Security card, proof of citizenship or legal residency (such as a passport or green card), and proof of age (such as a birth certificate). Walk-in appointments are available, but you may wait longer than if you call ahead to schedule a time.

What documents you need to have ready

Have your Social Security number available — this is the primary identifier Social Security uses to process your enrollment. You will also need your date of birth and citizenship status (U.S. citizen, permanent resident, or visa type).

If you are explore in person or by mail, bring proof of citizenship or legal residency. Acceptable documents include a U.S. passport, birth certificate, naturalization certificate, permanent resident card (green card), or visa. If you are explore online or by phone, Social Security can often verify your status through existing records, but be prepared to provide this information if asked.

If you have delayed claiming Social Security benefits and are now enrolling in Medicare Part A only, Social Security will ask whether you want to claim retirement benefits at the same time. You can enroll in Part A without claiming benefits, but you must tell Social Security explicitly that you want to do so.

What happens after you enroll

Social Security processes Medicare enrollments within two to four weeks. You will receive your Medicare card by mail at the address on file with Social Security. The card shows your Medicare number, which is now your Social Security number followed by a letter (usually A, B, or D).

Your Part A coverage begins on the first day of the month in which you turn 65, or on the first day of the month after you enroll, whichever is later. For example, if you turn 65 on March 15 and enroll in April, your coverage begins May 1. If you enroll before you turn 65, your coverage begins the month you turn 65.

Once you have Part A, you can choose whether to enroll in Part B (medical insurance) and Part D (prescription drug coverage). Part B has its own enrollment rules and important date. If you do not enroll in Part B during your initial enrollment period and you do not have other creditable coverage, you will face a permanent penalty on Part B premiums as well.

When to contact Social Security if something goes wrong

If you do not receive your Medicare card within four weeks of enrolling, contact Social Security at 1-800-772-1213 to check the status. Have your confirmation number ready if you enrolled online.

If your Medicare card arrives but contains incorrect information (wrong name, wrong date of birth, or wrong Medicare number), contact Social Security when ready. Errors on your card can cause problems when you try to use your benefits. Social Security can issue a corrected card within one to two weeks.

If you enrolled late and believe you should not face a penalty because you had creditable coverage, contact Social Security before your first bill arrives. You will need to provide documentation of your previous coverage. Social Security can remove the penalty if your claim is approved, but you must request this before you are billed.

Frequently Asked Questions

Do I have to enroll in Part B at the same time as Part A?

No. You can enroll in Part A without Part B. However, if you do not enroll in Part B during your initial enrollment period and do not have other creditable coverage, you will face a permanent penalty when you do enroll. Part B has the same seven-month initial enrollment window as Part A.

What if I am still working and do not want Medicare yet?

You can delay enrolling in Part A if you are still working and covered by your employer's health plan, but you must enroll by age 65 or within eight months of leaving your job, whichever comes first. Delaying past these important date triggers the permanent penalty. Contact Social Security to confirm your specific important date based on your work status.

Can my spouse enroll in Medicare at the same time I do?

Your spouse must enroll separately using their own Social Security number and enrollment window. Your spouse's initial enrollment period is based on their own 65th birthday, not yours. If your spouse is younger than 65, they cannot enroll in Medicare until they turn 65, with limited exceptions for disability.

What if I am not a U.S. citizen?

You can enroll in Medicare Part A at 65 if you are a permanent resident (green card holder) or have a valid visa. You will need to provide proof of your legal status when you enroll. Non-citizens without legal residency status cannot enroll in Medicare.

Will enrolling in Medicare Part A affect my immigration status?

No. Enrolling in Medicare Part A does not affect your immigration status or your path to citizenship. Medicare is a health insurance program, not a public benefit that counts against immigration applications. You can enroll safely regardless of your immigration plans.