How Medicare Part A enrollment works

You do not have to take any action to get Medicare Part A if you are already receiving Social Security benefits. Social Security will enroll you automatically three months before you turn 65, and your coverage starts the month you turn 65. Your Medicare card will arrive in the mail about two weeks before your coverage begins.

If you are not yet receiving Social Security, you must contact Social Security yourself to enroll in Medicare Part A. This is the step most people miss — the system does not find you on its own. You have a window of time around your 65th birthday to enroll without penalty, but waiting past that window can cost you more in premiums later.

Part A covers hospital stays, skilled nursing facility care, hospice, and home health services. There is no monthly premium for most people who have worked and paid Medicare taxes for at least 10 years. If you have not worked that long, you may pay a premium, which varies based on your work history.

Key Takeaways

  • If you receive Social Security, Medicare Part A enrollment happens automatically three months before your 65th birthday.
  • If you do not receive Social Security, you must contact Social Security directly to enroll in Medicare Part A.
  • Your initial enrollment window is seven months long: three months before your birthday, the month you turn 65, and three months after.
  • Enrolling late outside your initial window can result in a permanent increase to your Part A premium if you did not have other may have access to coverage.
  • You can enroll online at ssa.gov, by phone at 1-800-772-1213, or in person at your local Social Security office.

When your enrollment window opens and closes

Your Initial Enrollment Period is seven months long and centers on your 65th birthday. It runs from three months before the month you turn 65, through the month you turn 65, and for three months after. For example, if you turn 65 in June, your window opens in March and closes in September.

If you miss this window and do not have other health coverage that counts as "creditable coverage" (such as an employer plan or TRICARE), you will pay a permanent penalty on your Part A premium. The penalty is 10 percent of the standard premium for each full year you could have had Part A but did not enroll. This penalty stays with you for life, so enrolling late is expensive.

If you were covered by an employer health plan while you were still working, or if your spouse's employer covered you, that counts as creditable coverage. In that case, you have eight months after your employer coverage ends to enroll in Medicare Part A without penalty. Keep documentation of when your coverage ended — you will need it if you enroll late.

How to enroll if you receive Social Security

Check your Social Security account online at ssa.gov/myaccount to confirm that Social Security has your correct birth date and contact information. Social Security uses this information to send your Medicare card to the right address at the right time. If anything is wrong, update it before your enrollment window opens.

You do not need to do anything else. Social Security will send you a notice about your Medicare Part A enrollment, and your card will arrive by mail. The notice usually comes about two weeks before your coverage starts. If you do not receive a notice or card by the time your coverage should begin, call Social Security at 1-800-772-1213 to confirm your enrollment.

How to enroll if you do not receive Social Security

Contact Social Security directly to enroll in Medicare Part A. You can do this in three ways: online at ssa.gov, by phone at 1-800-772-1213, or in person at your local Social Security office. The online option is fastest if you have a Social Security account set up already.

When you contact Social Security, have your Social Security number, birth certificate or passport, and proof of citizenship or legal residency ready. If you are explore online, you can upload documents or mail them later. By phone or in person, you can show originals or certified copies.

Social Security will tell you when your Part A coverage will start. For most people, it starts the first day of the month you turn 65. You will receive your Medicare card in the mail within two weeks of enrollment. If you enroll before your 65th birthday, your card will arrive before your coverage begins.

What documents you need to have ready

Gather these documents before you contact Social Security:

  • Your Social Security number
  • Proof of citizenship or legal residency (U.S. birth certificate, passport, naturalization papers, or permanent resident card)
  • Proof of age (birth certificate or passport)
  • Current mailing address and phone number
  • If you are explore based on a spouse's work record, your spouse's Social Security number and birth date

If you are explore online, you can upload images of these documents or mail them to Social Security after you submit your process. If you are explore by phone, Social Security will tell you where to mail originals or certified copies. In-person applications at a Social Security office let you show documents when ready.

If you do not have a birth certificate, you can use a passport, military discharge papers, or other government-issued ID that shows your date of birth. Social Security has a list of acceptable documents on its website.

What happens after you enroll

After Social Security processes your enrollment, you will receive a Medicare card in the mail. The card shows your Medicare number, the date your coverage starts, and which parts of Medicare you have (Part A, Part B, or both). Keep this card in a safe place — you will need to show it to doctors and hospitals.

Your Part A coverage begins on the first day of the month you turn 65, or the first day of the month after Social Security approves your enrollment, whichever is later. If you enroll before your birthday, your coverage still does not start until the month you turn 65.

If you also want Medicare Part B (which covers doctor visits and outpatient care), you must enroll separately during the same Initial Enrollment Period. Part B has a monthly premium that varies by income. Many people enroll in both Part A and Part B at the same time, but you can enroll in Part A alone if you are still working and have employer coverage.

Common mistakes to avoid

The biggest mistake is assuming Social Security will find you automatically if you are not receiving benefits. It will not. If you are not on Social Security, you must contact Social Security yourself, and you must do it during your seven-month Initial Enrollment Period. Waiting until after your 65th birthday is too late if you miss the window.

Another common mistake is not keeping records of employer coverage. If you were covered by an employer health plan when you turned 65, that coverage may extend your enrollment important date by eight months. But you need to prove when that coverage ended. Keep your final insurance card, termination letter, or COBRA paperwork.

Do not assume you have to pay a premium for Part A. Most people who have worked and paid Medicare taxes for at least 10 years pay no monthly premium. If you are told you owe a premium, ask Social Security to explain why — it may be a mistake, or you may may have access to for a reduced premium based on your work history.

Frequently Asked Questions

What if I am still working at 65 and have employer health insurance?

You can delay enrolling in Medicare Part B, but you should still enroll in Medicare Part A. Part A does not conflict with employer coverage, and enrolling in Part A does not affect your employer plan. If you delay Part B, you have eight months after your employer coverage ends to enroll without penalty.

Can I enroll in Medicare Part A after I turn 65?

Yes, but only during your seven-month Initial Enrollment Period (three months before your birthday through three months after). If you miss this window and do not have creditable coverage, you will pay a permanent 10 percent penalty on your Part A premium for each year you delayed.

Do I have to pay a monthly premium for Part A?

Most people pay no monthly premium for Part A if they or their spouse worked and paid Medicare taxes for at least 10 years. If you have not worked that long, you may pay a premium. Social Security will tell you the amount when you enroll.

What if my Social Security card or Medicare card gets lost?

You can request a replacement Social Security card at ssa.gov or at your local Social Security office. For a replacement Medicare card, visit Medicare.gov or call 1-800-MEDICARE (1-800-633-4227). Both can be replaced at no cost.

Can I enroll in Medicare Part A online?

Yes, if you do not receive Social Security. You can create an account at ssa.gov/myaccount and enroll online. You can upload documents or mail them later. If you already receive Social Security, enrollment happens automatically and you do not need to do anything online.