How to Enroll in Medicare When You Turn 65

You become may be able to access for Medicare at 65, and you enroll through Social Security, Medicare.gov, or your local Social Security office

Medicare enrollment happens in two main ways: automatically, if you are already receiving Social Security benefits, or by taking action yourself if you are not. Most people become may be able to access on the first day of the month they turn 65. If you are still working and do not yet receive Social Security, you will need to contact Social Security to enroll in Medicare separately. The process is straightforward, but the timing matters — missing your enrollment window can cost you in penalties that last for life.

Your enrollment window is seven months long: three months before the month you turn 65, the month itself, and three months after. This is called your Initial Enrollment Period, and it is the only time you can enroll without facing permanent penalties.

Key Takeaways

You can enroll in Medicare starting three months before the month you turn 65 and continuing for three months after — a seven-month window called your Initial Enrollment Period.
If you are receiving Social Security, Medicare Part A and Part B are usually enrolled automatically, but you should still verify your coverage about a month before your 65th birthday.
If you are not receiving Social Security, you must contact Social Security directly by phone, online at Medicare.gov, or in person at your local office to enroll in Medicare.
Delaying enrollment past your Initial Enrollment Period can result in permanent late-enrollment penalties on your monthly premiums unless you have creditable coverage from an employer or union.
You can enroll in prescription drug coverage (Part D) and supplemental insurance (Medigap) during the same window, and these choices affect your out-of-pocket costs.

The Initial Enrollment Period: Your seven-month window

Your Initial Enrollment Period begins three months before the month you turn 65 and ends three months after. For example, if you turn 65 in June, you can enroll from March through September. This is the easiest time to enroll because you face no penalties for waiting, and you have the most flexibility in choosing your coverage.

During this window, you can enroll in Medicare Part A (hospital insurance) and Part B (medical insurance), add prescription drug coverage (Part D), and purchase supplemental insurance (Medigap) if you want it. You do not have to make all these choices at once, but making them together often saves money because some important date overlap. Your coverage will begin on the first day of the month you turn 65, regardless of when during the seven-month window you enroll.

Automatic enrollment: What happens if you receive Social Security

If you are already receiving Social Security retirement, disability, or survivor benefits when you turn 65, Medicare Part A and Part B are usually enrolled for you automatically. Social Security will send you a notice about two months before your 65th birthday explaining your coverage. You do not need to do anything unless you want to decline Part B, which is rare but possible if you have employer coverage.

Even though enrollment is automatic, you should verify the information in that notice. Check that your name, address, and date of birth are correct. If anything is wrong, contact Social Security at 1-800-772-1213 to correct it before your coverage begins. You will also receive your Medicare card in the mail about a week before your coverage starts. Do not wait for the card to arrive — your coverage is active on the date Social Security specifies in the notice.

Manual enrollment: What to do if you are not receiving Social Security

If you are still working or have delayed claiming Social Security, you must enroll in Medicare yourself. You have three ways to do this: online at Medicare.gov, by phone at 1-800-MEDICARE (1-800-633-4227), or in person at your local Social Security office.

The online method at Medicare.gov is usually the fastest. You will need your Social Security number, proof of citizenship or legal residency, and information about any current health insurance. By phone, a Social Security representative will walk you through the same questions. In person, bring your Social Security card, proof of citizenship (passport, birth certificate, or naturalization papers), and proof of residency (utility bill or lease). Processing typically takes two to four weeks, so enroll early in your seven-month window to may support coverage begins on time.

What happens if you miss your Initial Enrollment Period

If you do not enroll during your seven-month window and do not have a valid reason for the delay, you will face a late-enrollment penalty. For Part B, the penalty is 10 percent of the standard premium for each full year you were may be able to access but not enrolled. This penalty is permanent — it stays on your monthly bill for as long as you have Medicare. For Part D (prescription drugs), the penalty is 1 percent of the national average premium for each month you were late, also permanent.

The main exception is creditable coverage — continuous health insurance through an employer, union, or COBRA that is at least as good as Medicare. If you had creditable coverage when you turned 65, you can enroll in Medicare later without penalty, as long as you enroll within 63 days of losing that coverage. You will need to prove you had creditable coverage, so keep your insurance documents, termination letters, and any written confirmation from your employer about coverage dates.

Choosing Part D and Medigap during your enrollment window

Part D covers prescription drugs, and Medigap (supplemental insurance) covers costs that Original Medicare does not — copayments, coinsurance, and deductibles. Both have enrollment important date tied to your Initial Enrollment Period, though the rules differ slightly.

For Part D, you can enroll anytime during your seven-month Initial Enrollment Period. If you delay past that window and do not have creditable coverage, you pay a permanent penalty. For Medigap, you have a six-month window starting the month you turn 65 and enroll in Part B. During this window, insurance companies cannot deny you coverage or charge you more because of pre-existing conditions — a protection that disappears after six months. If you wait to buy Medigap after this window closes, insurers can refuse to sell to you or charge much higher premiums.

Documents you will need to have ready

Whether you enroll online, by phone, or in person, have these documents nearby: your Social Security number, proof of citizenship or legal residency (passport, birth certificate, or naturalization papers), and your current health insurance information if you have it. If you are enrolling by phone or in person, also bring a photo ID.

If you are enrolling because you are losing employer coverage, have your coverage termination letter or final pay stub showing the end date. If you are claiming that you had creditable coverage after 65, gather documentation of that coverage — insurance cards, policy documents, or a letter from your employer confirming dates of coverage. Having these ready before you call or visit will speed up the process.

Frequently Asked Questions

Can I enroll in Medicare before I turn 65?

Yes. Your Initial Enrollment Period starts three months before the month you turn 65. You can enroll online at Medicare.gov, by phone at 1-800-MEDICARE, or at your local Social Security office. Enrolling early ensures your coverage begins on your 65th birthday.

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

You can delay enrolling in Part B without penalty as long as your employer coverage is based on your current employment and you work for a company with 20 or more employees. You must enroll in Part A. When you leave your job or lose coverage, you have 63 days to enroll in Part B without penalty. Keep documentation of your employer coverage dates.

Do I have to enroll in Part B, or can I take only Part A?

You can enroll in Part A alone, but Part B covers doctor visits and outpatient care that Part A does not. If you decline Part B during your Initial Enrollment Period and later change your mind, you will pay a permanent penalty unless you have a valid reason for the delay, such as creditable employer coverage.

What is the difference between Original Medicare and Medicare Advantage?

Original Medicare is Part A and Part B run by the federal government. Medicare Advantage (Part C) is an alternative plan run by private insurance companies that covers the same services but often includes prescription drugs and has different copayments and networks. You choose one or the other during enrollment, not both.

How long does it take to receive my Medicare card after I enroll?

If you enroll online or by phone, your card typically arrives within 7 to 10 business days. If you enroll in person at a Social Security office, processing may take up to two weeks. You can use your Social Security number as your Medicare number while you wait for the card to arrive.

This guide is for general information only and is not medical, financial, legal, or other professional advice. For decisions specific to your situation, consult a qualified professional. See our Editorial Policy.