Where to sign up for Medicare Part B

You sign up for Medicare Part B through Social Security, either online at ssa.gov, by phone at 1-800-772-1213, or in person at your local Social Security office. You can also contact Medicare directly at 1-800-MEDICARE (1-800-633-4227) if you prefer, though Social Security handles most enrollments. The online route is fastest — you can complete it in 10 to 15 minutes without waiting on hold.

Timing matters because Medicare Part B has enrollment periods with different rules. If you miss your window, you may pay a permanent penalty on your premiums. The three main enrollment periods are Initial Enrollment Period (the seven months around your 65th birthday), General Enrollment Period (January 1 through March 31 each year), and Special Enrollment Period (if you had employer coverage or meet other conditions).

Key Takeaways

  • You enroll through Social Security online, by phone, or at a local office — Medicare itself does not process enrollments, only answers questions about coverage.
  • Your Initial Enrollment Period runs for three months before and three months after the month you turn 65, and missing it triggers a permanent 10 percent premium increase for each year you delay.
  • If you are still working and have health insurance through your employer, you may have a Special Enrollment Period that lets you delay Part B without penalty.
  • You will need your Social Security number, birth date, and information about any current health coverage when you enroll.
  • Part B coverage typically starts the first day of the month after you enroll, though timing depends on when you submit your request.

Understanding your enrollment period and important date

Your Initial Enrollment Period is seven months long: three months before the month you turn 65, the month you turn 65, and three months after. If you enroll during the three months before or during your birth month, coverage starts January 1 of the following year. If you enroll in the three months after your birth month, coverage starts the first day of the month after you enroll.

If you miss your Initial Enrollment Period, you can enroll during General Enrollment Period (January 1 through March 31 each year), but coverage does not start until July 1 of that year. More importantly, you will owe a permanent penalty: your monthly premium increases by 10 percent for each full 12-month period you were may be able to access but did not enroll. This penalty stays on your account for life.

A Special Enrollment Period lets you enroll without penalty if you had employer coverage (yours or a spouse's) and did not sign up for Part B when first may be able to access. You have eight months from the date your employer coverage ends or you stop working, whichever comes first. This is the main exception to the penalty rule.

What documents and information you need

Before you contact Social Security, gather your Social Security number, date of birth, and citizenship or immigration status. You will also need information about any current health coverage — the name of your employer or spouse's employer, the plan name, and your policy number if you have one. If you are explore by mail, you may need to provide a copy of your birth certificate or passport.

If you are still working or your spouse is still working, have that employer's name and the date you or your spouse plan to retire. Social Security uses this information to determine whether you may have access to for a Special Enrollment Period. If you have had a gap in coverage or a life event (marriage, divorce, loss of coverage), note the date it happened.

Enrolling online through Social Security

Go to ssa.gov and create a my Social Security account if you do not already have one. You will need an email address and a phone number. Once logged in, look for the option to "Manage your benefits" and select "Medicare." The online form asks for your birth date, current coverage status, and whether you are still working. Answer honestly about employer coverage — Social Security cross-checks this information with your employer records.

The form takes about 10 to 15 minutes. At the end, you will see a confirmation page with a reference number. Write this down or print it. Social Security will mail you a notice within two weeks confirming your enrollment and your coverage start date. If you do not receive anything within three weeks, call 1-800-772-1213 to confirm your request went through.

Enrolling by phone or in person

Call Social Security at 1-800-772-1213 Monday through Friday, 7 a.m. to 7 p.m. your local time. Have your Social Security number, birth date, and current coverage information ready. The call usually takes 15 to 20 minutes. Ask the representative to mail you a written confirmation of your enrollment and coverage start date — do not rely on what you hear over the phone.

To enroll in person, find your local Social Security office at ssa.gov/locator or call the main number above. Bring your Social Security card, birth certificate or passport, and information about any current health coverage. Walk-in appointments are available but wait times vary; you can also schedule an appointment online or by phone. In-person enrollment takes 20 to 30 minutes and you will receive a receipt before you leave.

What happens after you enroll

Social Security will mail you a Medicare card within two to four weeks of your enrollment. Your card shows your Medicare number (which is now your Social Security number followed by a letter), your coverage type, and your coverage start date. Keep this card in a safe place — you will need it every time you see a doctor or fill a prescription.

Your Part B premium is deducted from your Social Security check each month, starting the month your coverage begins. If you are not yet receiving Social Security, Medicare will bill you directly. The premium amount changes each year; Social Security will notify you of the new amount in October for the following year. If you cannot afford the premium, you may be able to get help through Medicaid or other programs — contact your state Medicaid office to ask.

Common mistakes to avoid

The biggest mistake is waiting too long to enroll. If you turn 65 and do not enroll during your Initial Enrollment Period, you will owe a permanent penalty even if you enroll later. The only exception is a Special Enrollment Period, which requires proof that you had employer coverage. Do not assume you can enroll anytime — the penalty is real and it never goes away.

Another mistake is not telling Social Security about employer coverage. If you or your spouse is still working and have health insurance through that job, say so when you enroll. This may may have access to you for a Special Enrollment Period and protect you from the penalty. Social Security will ask directly, but some people answer incorrectly because they think it does not matter.

Do not enroll in Part B if you are covered by TRICARE (military health insurance) or the Veterans Health Administration. These programs conflict with Medicare Part B, and enrolling can cause billing problems. If you have either of these, contact that program before you enroll in Medicare to understand how they work together.

Frequently Asked Questions

Can I enroll in Part B after I turn 65 if I missed the important date?

Yes, you can enroll during General Enrollment Period (January 1 through March 31), but your coverage will not start until July 1 and you will owe a permanent 10 percent premium penalty for each year you delayed. If you had employer coverage, you may may have access to for a Special Enrollment Period with no penalty — contact Social Security to ask.

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

If you or your spouse have employer health coverage, you can delay Part B without penalty. You have eight months after your employment ends to enroll without owing the late penalty. Tell Social Security about your employer coverage when you first become may be able to access so they note your Special Enrollment Period.

Do I have to enroll in Part B if I have Medicare Part A?

Part A and Part B are separate. You can have Part A (hospital insurance) without Part B (doctor and outpatient care). However, if you do not enroll in Part B when first may be able to access and later change your mind, you will owe the permanent penalty unless you had employer coverage or another may have access to reason.

How much does Medicare Part B cost?

The standard Part B premium changes each year. For 2024, it is $164.90 per month for most people, though higher earners pay more through Income-Related Monthly Adjustment Amounts (IRMAA). Contact Medicare at 1-800-MEDICARE or check Medicare.gov for the current year's premium.

What if Social Security loses my enrollment request?

This is rare, but if you do not receive a Medicare card or confirmation within four weeks, call Social Security at 1-800-772-1213 with your reference number from your online enrollment or your confirmation receipt. They can look up your request and resend your card or resubmit if something went wrong.