You can sign up for Medicare starting three months before the month you turn 65

Medicare enrollment opens on the first day of the month three months before your 65th birthday and closes on the last day of the month after you turn 65. That is a seven-month window. You do not have to wait until your birthday month itself — you can start the process as soon as that first window opens, and many people do because it gives you time to compare plans and avoid gaps in coverage.

The three main ways to sign up are online through Medicare.gov, by phone with a Medicare representative, or in person at your local Social Security office. Online is usually fastest if you have your Social Security number and basic health information handy. The phone line is 1-800-MEDICARE (1-800-633-4227), and representatives can walk you through the whole process in one call.

You will need your Social Security number, proof of citizenship or legal residency (your birth certificate, passport, or naturalization papers), and information about any current health coverage you have. If you are still working and covered by an employer plan, bring details about that coverage too — it affects which Medicare parts you should choose.

Key Takeaways

  • Your enrollment window opens three months before you turn 65 and closes one month after, giving you seven months total to sign up without penalty.
  • You can sign up online at Medicare.gov, by phone at 1-800-MEDICARE, or at your local Social Security office.
  • If you delay signing up past your enrollment window and do not have other may have access to coverage, you may pay a permanent penalty on your premiums.
  • Medicare Part A (hospital insurance) is usually free if you or your spouse paid Medicare taxes for at least 10 years, but you still must sign up for it.
  • Part B (medical insurance) has a monthly premium, and you choose whether to enroll when you turn 65 or wait until later if you have employer coverage.

What happens if you miss your enrollment window

If you do not sign up during your seven-month window and you do not have other may have access to coverage — such as an active employer health plan or TRICARE — you will owe a late enrollment penalty. This penalty is a percentage added to your Part B and Part D premiums, and it stays with you for as long as you have Medicare.

The Part B penalty is 10 percent of the standard premium for each full year you were may be able to access but did not enroll. The Part D penalty (for prescription drug coverage) is calculated differently but works the same way — it is permanent. You can still sign up after your window closes, but the penalty applies when ready and does not go away.

The only way to avoid the penalty is to have had other health coverage that counts as "creditable coverage" during the time you were not enrolled in Medicare. Employer plans, TRICARE, the Veterans Health Administration, and some other group plans count. Individual health insurance plans usually do not. If you had creditable coverage, keep proof of it — you may need to show it to Medicare to have the penalty waived.

Part A versus Part B: which one you must choose

Part A covers hospital stays, skilled nursing care, hospice, and some home health services. Most people do not pay a monthly premium for Part A if they or their spouse paid Medicare taxes for at least 10 years. Even if you do not owe premiums, you must still sign up for it — it does not happen automatically just because you turned 65.

Part B covers doctor visits, outpatient care, lab work, and some preventive services. Part B has a monthly premium (the standard amount changes each year). You have a choice: you can enroll in Part B when you turn 65, or you can delay if you are still working and covered by an employer health plan. If you delay, you have eight months after your employment ends or your employer coverage stops to sign up without penalty.

If you are not working and not covered by an employer plan, sign up for Part B during your initial enrollment window. Waiting means paying the late enrollment penalty for the rest of your life.

Part D and Medigap: coverage choices you make at the same time

Part D is prescription drug coverage. It is optional, but like Part B, if you do not enroll when you first become may be able to access and you do not have other creditable drug coverage, you will pay a permanent penalty. You choose a Part D plan from private insurance companies during your enrollment window. Plans vary in which drugs they cover and what you pay, so comparing a few options before you choose is worth the time.

Medigap (also called supplemental insurance) is a separate policy sold by private insurers that covers costs Medicare does not — copayments, coinsurance, and deductibles. It is not required, but many people find it reduces their out-of-pocket costs. If you want Medigap, you have a six-month window starting the month you turn 65 and are enrolled in Part B to buy a policy without medical underwriting. After that window closes, insurers can deny you or charge more based on your health history.

You do not buy Medigap through Medicare — you contact private insurance companies directly. Common insurers include AARP/UnitedHealthcare, Humana, Cigna, and regional carriers. Prices and coverage vary widely, so getting quotes from several companies is standard practice.

How to sign up online at Medicare.gov

Go to Medicare.gov and click "Sign Up for Medicare" on the homepage. You will be asked to create a login or sign in with an existing account. Have your Social Security number, date of birth, and email address ready.

The form will ask whether you are signing up for the first time at 65, whether you are still working, and whether you have other health coverage. Answer honestly — your answers determine which parts you can enroll in and whether penalties explore. You will also enter information about your citizenship or residency status.

After you submit, Medicare will send you a confirmation. You do not receive your Medicare card when ready — it usually arrives by mail within two to four weeks. You can use your confirmation number to access your account online in the meantime. If you need your card sooner, you can print a temporary version from your online account.

Signing up by phone or in person

Call 1-800-MEDICARE (1-800-633-4227) and tell the representative you want to sign up for Medicare at 65. Have your Social Security number, date of birth, citizenship information, and details about any current health coverage available. The call usually takes 15 to 20 minutes. The representative will confirm your enrollment and tell you when to expect your Medicare card.

You can also walk into your local Social Security office without an appointment and ask to sign up for Medicare. Bring the same documents: Social Security number, proof of citizenship or residency, and information about current coverage. Processing times vary by office, but you will receive a confirmation before you leave.

Both phone and in-person routes are free. You do not need to pay anyone to help you sign up for Medicare, and you should be suspicious of anyone asking for money to do it.

What to do after you sign up

Once you have enrolled in Part A and Part B, you will receive a Medicare card in the mail. Check it for errors — your name, date of birth, and Social Security number should be correct. If something is wrong, contact Medicare right away to correct it.

If you also chose Part D or Medigap, those policies have separate enrollment and separate cards or documents. Keep all of them in a safe place. You will need your Medicare card when you see a doctor, go to the hospital, or fill a prescription.

Before your coverage starts, schedule a preventive visit with your primary care doctor. Medicare covers an annual wellness visit at no cost to you, and it is a good time to make sure your doctor knows you have Medicare and to discuss any medications or health concerns.

Frequently Asked Questions

Can I sign up for Medicare before I turn 65?

Yes. Your enrollment window opens three months before the month you turn 65. If your birthday is in June, you can sign up starting in March. Many people sign up early to avoid last-minute confusion and to have time to choose between Part D and Medigap plans.

What if I am still working at 65?

You must still sign up for Part A (hospital insurance) even if you are working. For Part B, you can delay if your employer has 20 or more employees and you are covered by their health plan. Once you stop working or lose that coverage, you have eight months to sign up for Part B without penalty. Talk to your employer's benefits office about your specific situation.

Do I have to choose a Medigap plan when I sign up for Medicare?

No. Medigap is optional. However, if you want it, you have the best rates and easiest approval during a six-month window starting when you turn 65 and enroll in Part B. After that window, insurers can deny you or charge more. You can always buy Medigap later, but waiting costs more.

What if I am on my spouse's health insurance and they are not yet 65?

You still must sign up for Medicare at 65. Your spouse's coverage does not count as creditable coverage for you. Sign up during your enrollment window to avoid penalties. You can stay on your spouse's plan as secondary insurance if you want, but Medicare becomes your primary coverage.

How do I know if my current coverage counts as creditable coverage?

Ask your health plan directly whether it is creditable coverage for Medicare purposes. Your employer benefits office or insurance company can tell you. If you have creditable coverage, keep written proof — you may need it to avoid late enrollment penalties if you delay signing up for Part B or Part D.