Where to sign up depends on when you turn 65 and whether you already get Social Security

You can sign up for Medicare through Social Security, Medicare.gov, or by calling Medicare directly at 1-800-MEDICARE. If you are already receiving Social Security benefits, Medicare will contact you automatically about three months before your 65th birthday and enroll you in Parts A and B unless you tell them not to. If you are not yet receiving Social Security, you will need to contact one of these three sources yourself during your enrollment window.

The easiest route for most people is to go online to Medicare.gov and use the sign-up tool, which takes about 10 minutes. You will need your Social Security number, proof of citizenship or legal residency, and information about any current health coverage. If you prefer to sign up by phone, Medicare representatives can walk you through the same questions, though wait times vary by season.

Key Takeaways

  • If you receive Social Security, Medicare enrolls you automatically three months before you turn 65 — you do not need to do anything unless you want to decline Part B.
  • If you do not receive Social Security, you must sign up yourself through Medicare.gov, by phone at 1-800-MEDICARE, or at your local Social Security office during your enrollment window.
  • Your initial enrollment period is seven months long: three months before the month you turn 65, the month itself, and three months after.
  • If you miss your initial enrollment window and do not have other health coverage, you may pay a penalty on your premiums for as long as you have Medicare.

When your enrollment window opens and closes

Your initial enrollment period is seven months total. It starts three months before the month you turn 65, includes the month of your birthday, and ends three months after. For example, if you turn 65 in June, your window runs from March through September. You can sign up anytime during this window, and coverage will begin on the first day of the month you turn 65 or the first day of the month after you sign up, whichever is later.

If you miss this window, you can still sign up during the general enrollment period, which runs January 1 through March 31 each year. However, coverage will not start until July 1 of that year, and you may owe a permanent penalty on your Part B and Part D premiums if you did not have other may have access to coverage in the meantime. The penalty is 10 percent of the Part B premium for each full year you were may be able to access but not enrolled.

What information you need to have ready

Before you start, gather your Social Security number, date of birth, and citizenship or legal residency documentation. You will also need information about any current health insurance — the name of your plan, your policy number, and the dates you have been covered. If you are still working and covered through your employer, bring that information too, because it may affect when you need to sign up for Part B.

Have your bank account information available if you want to set up automatic premium payments, though you can arrange this later. If you are signing up by phone, having these details written down will speed up the call. If you are signing up online, you can save your progress and come back to finish later.

Signing up online at Medicare.gov

Go to Medicare.gov and look for the "Sign Up" button on the homepage. You will create a Medicare.gov account using your email address and a password. Once you are logged in, select "Sign Up for Medicare" and answer questions about your age, citizenship, and current coverage. The system will tell you which parts of Medicare you are may be able to access for and when your coverage can start.

After you complete the form, you will see a summary of what you signed up for. Print or save this page — you will need it to track your coverage start date and to contact Medicare if something is wrong. Medicare will send you a confirmation letter in the mail within two weeks. If you do not receive it, call 1-800-MEDICARE to confirm your enrollment went through.

Signing up by phone or in person

Call 1-800-MEDICARE (1-800-633-4227) to sign up over the phone. Representatives are available Monday through Friday, 8 a.m. to 8 p.m. Eastern time. Have your Social Security number and current insurance information ready. The call usually takes 15 to 20 minutes. Ask for a confirmation number before you hang up, and write down the date and time of your call.

You can also visit your local Social Security office in person to sign up for Medicare. Find your nearest office at ssa.gov or call Social Security at 1-800-772-1213. Bring your Social Security card, proof of citizenship or legal residency, and information about any current health coverage. Processing in person takes about 30 minutes, and you will receive a receipt on the spot.

What happens after you sign up

Medicare will send you a Medicare card in the mail within two weeks of your enrollment. This card shows your Medicare number and which parts of Medicare you are enrolled in. Do not wait for the card to arrive before your coverage starts — your coverage begins on the date Medicare told you, even if the card has not arrived yet. You can use your Social Security number as your Medicare number until the card arrives.

You will also receive information about your premiums and when they are due. Part A (hospital insurance) has no monthly premium for most people. Part B (medical insurance) has a monthly premium that is deducted from your Social Security check if you receive benefits, or billed separately if you do not. If you enrolled in Part D (prescription drug coverage) or a Medicare Advantage plan, you will receive separate materials about those plans.

If you need to make changes after signing up

You can change your Medicare coverage during the Annual Enrollment Period, which runs October 15 through December 7 each year. Changes take effect January 1 of the following year. You can switch from Original Medicare to a Medicare Advantage plan, drop Part D coverage, or add it back. You cannot drop Part A or Part B during this period unless you have other may have access to coverage.

If you have a major life change — such as losing employer coverage, moving to a new state, or becoming may be able to access for Medicaid — you may be able to make changes outside the annual enrollment period. Call Medicare at 1-800-MEDICARE to ask whether your situation qualifies for a special enrollment period.

Frequently Asked Questions

What if I am still working at 65 — do I have to sign up for Medicare?

You must sign up for Part A (hospital insurance) even if you are still working, because it is free for most people. You can delay Part B if you have health insurance through your current employer and your employer has 20 or more employees. However, sign up for Part B within eight months of leaving that job to avoid a permanent penalty.

Can I sign up for Medicare before I turn 65?

No. Your enrollment window opens three months before the month you turn 65. If you try to sign up earlier, the system will not let you. If you are younger than 65 and have End-Stage Renal Disease or ALS, you may be able to sign up earlier — call Medicare at 1-800-MEDICARE to ask.

What if I miss my enrollment window?

You can sign up during the general enrollment period (January 1 through March 31), but coverage will not start until July 1, and you will owe a permanent 10 percent penalty on your Part B premium for each year you were may be able to access but not enrolled. If you had other may have access to coverage during the gap, you may not owe the penalty — ask Medicare to review your situation.

Do I have to choose a plan when I sign up, or can I do that later?

You can sign up for Original Medicare (Parts A and B) without choosing a specific plan. If you want Part D (prescription drug coverage) or a Medicare Advantage plan, you should choose one during your enrollment window. If you do not choose Part D during your initial enrollment period, you may owe a penalty when you add it later.

What if I signed up but my information was wrong?

Call Medicare at 1-800-MEDICARE as soon as you notice the error. They can correct your name, address, Social Security number, or coverage dates. Bring your Medicare card and any documents that show the correct information. Corrections usually take two to four weeks to process.