You are automatically enrolled in Medicare Part A at 65, but Part B enrollment is your choice

Most people are enrolled in Medicare Part A (hospital insurance) automatically when they turn 65, without filling out any forms or contacting Medicare. This happens because you or your spouse paid Medicare taxes while working. You will receive a Medicare card in the mail about three months before your 65th birthday showing your Part A coverage.

Medicare Part B (medical insurance for doctor visits and outpatient care) is different. You are not automatically enrolled in Part B. Instead, you must choose whether to take it, and the important date to say yes or no without a penalty is your Initial Enrollment Period — a seven-month window that starts three months before the month you turn 65 and ends three months after.

If you miss that window and do not have other health coverage, you will pay a permanent 10 percent surcharge on your Part B premium for as long as you have Medicare. That surcharge adds up over time, so the choice matters.

Key Takeaways

  • Part A enrollment happens automatically at 65 if you or your spouse paid Medicare taxes; you do not need to do anything.
  • Part B requires you to make a choice during your Initial Enrollment Period, which runs from three months before to three months after your 65th birthday.
  • If you delay Part B past your Initial Enrollment Period and do not have other may have access to coverage, you will pay a 10 percent surcharge on your premium for life.
  • If you are still working and covered by your employer's health plan at 65, you may be able to delay Part B without penalty under Special Enrollment rules.
  • You will receive your Medicare card by mail; you do not need to request it.

What happens if you are still working at 65

If you are covered by your employer's health plan when you turn 65, you can delay enrolling in Part B without paying the surcharge — but only if your employer has 20 or more employees. This is called Special Enrollment, and it protects people who keep working.

You must enroll in Part B within eight months after your employer coverage ends or after you stop working, whichever comes first. If you miss that important date, the 10 percent surcharge applies again. Keep your employer coverage documents and the dates you were covered, because Medicare will ask for proof.

Part A enrollment for people who did not work in the United States

If you did not pay Medicare taxes through work but are a U.S. citizen or permanent resident aged 65 or older, you can enroll in Part A by paying a monthly premium. You are not automatically enrolled, and you must contact Medicare to sign up. The premium varies depending on how many years you or your spouse worked and paid taxes.

You have the same Initial Enrollment Period as everyone else — three months before to three months after your 65th birthday. If you miss it, you can enroll during the General Enrollment Period (January 1 to March 31 each year), but you will pay a 10 percent surcharge on your Part A premium for twice as long as you delayed.

How to confirm your automatic Part A enrollment

You do not have to do anything to receive Part A, but you can check your enrollment status before your 65th birthday by creating an account on Medicare.gov. Log in, go to "My Medicare", and look for your enrollment information. You can also call Medicare at 1-800-MEDICARE (1-800-633-4227) to confirm.

When your Medicare card arrives, check it for errors — your name, date of birth, and Medicare number should all be correct. If something is wrong, contact Medicare right away to have it fixed before you need to use your coverage.

What to do about Part B during your enrollment window

During your Initial Enrollment Period, you can enroll in Part B through Medicare.gov, by phone at 1-800-MEDICARE, or by visiting your local Social Security office. You will need your Social Security number and information about any current health coverage you have.

If you want Part B to start the first day of the month you turn 65, you must enroll by the end of the month before your birthday. If you enroll after that, your coverage will start the first day of the following month. Plan ahead so your coverage does not have a gap.

Automatic Part B enrollment for people receiving Social Security

If you are already receiving Social Security benefits when you turn 65, you are automatically enrolled in Part B unless you specifically ask not to be. Your Part B coverage will start the first day of the month you turn 65, and your premium will be deducted from your Social Security check.

You can decline Part B during your Initial Enrollment Period if you have other health coverage, such as an employer plan or TRICARE (military coverage). You must submit a written request to decline, and you should keep a copy for your records.

What happens if you turn 65 outside the United States

If you are living abroad when you turn 65, you are still automatically enrolled in Part A if you may have access to. However, Part A coverage does not work outside the U.S. except in very limited situations (Canada, Mexico, and some cruise ships near U.S. ports). You should still enroll in Part B during your Initial Enrollment Period if you plan to return to the U.S., because the surcharge rules still explore.

If you are a U.S. citizen living abroad and want to enroll in Medicare, contact the Social Security office that serves your area or call the U.S. Social Security Administration's international phone line.

Frequently Asked Questions

Do I need to do anything to get my Medicare card?

No. If you are automatically enrolled in Part A, Medicare will mail your card to you about three months before your 65th birthday. You do not need to request it. Check the mail carefully so you do not miss it, and contact Medicare if it does not arrive within a reasonable time.

What if I do not want Part B?

You can decline Part B during your Initial Enrollment Period by submitting a written request to Medicare. You must have other health coverage (such as an employer plan) to decline without penalty. If you change your mind later, you can enroll during General Enrollment (January 1 to March 31), but you will pay a surcharge.

Can I delay Part B if I am still working?

Yes, if your employer has 20 or more employees and you are covered by their health plan. You must enroll in Part B within eight months after your coverage ends or you stop working. If you miss that important date, the surcharge applies.

What is the penalty for missing the Part B enrollment important date?

You will pay a 10 percent surcharge on your Part B premium for as long as you have Medicare. The surcharge is permanent and does not go away. For example, if your premium is $200 per month, the surcharge adds $20 per month for life.

Do I have to enroll in Part D (prescription drug coverage) at 65?

Part D is optional, but if you do not enroll when you are first may be able to access and later want it, you will pay a surcharge. Your Initial Enrollment Period for Part D is the same as for Part B. If you have prescription drug coverage through an employer or other source, you may be able to delay without penalty.