You can sign up for Medicare starting at age 65, but the exact timing depends on whether you're still working and whether you have health coverage through your job

Most people become may be able to access for Medicare the month they turn 65. You don't have to wait until your birthday month ends — you can sign up as early as three months before you turn 65. However, if you're still working and covered by a group health plan through your employer, you may be able to delay signing up without penalty, as long as your employer has 20 or more employees. If you're self-employed or your employer has fewer than 20 employees, you should sign up when you turn 65 even if you're still working.

The key date to remember is your birthday month. Medicare enrollment happens in windows around that month, and missing the right window can mean delayed coverage or permanent premium increases. The rules are different depending on your situation — whether you have employer coverage, whether you're receiving Social Security, and whether you're turning 65 for the first time.

Key Takeaways

  • You become may be able to access for Medicare at 65, and you can sign up starting three months before your birthday month.
  • If you have health coverage through an employer with 20 or more employees, you can delay Medicare without penalty, but you must sign up within eight months of losing that coverage.
  • If you miss your initial enrollment window, you will pay a permanent penalty on your Part B and Part D premiums for as long as you have Medicare.
  • You can sign up online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.
  • If you're already receiving Social Security before 65, you will be signed up for Medicare automatically when you turn 65.

Your Initial Enrollment Window: The Seven-Month Period Around Your Birthday

Your Initial Enrollment Period lasts seven months total: three months before your birthday month, your birthday month itself, and three months after. For example, if you turn 65 in June, your enrollment window runs from March through September. During this window, you can sign up for Medicare Part A (hospital coverage) and Part B (medical coverage) without any waiting period or penalty.

You don't have to sign up on your birthday or even in your birthday month — you can sign up anytime during those seven months and your coverage can start as early as the first day of your birthday month. However, the earlier you sign up, the earlier your coverage begins. If you wait until after your birthday month to sign up, your coverage will start the first day of the month after you sign up.

This window is important because it's the only time you can sign up for Medicare without facing a permanent penalty. If you miss it and don't have a valid reason (called a "may have access to event"), you will pay more for Part B and Part D coverage for the rest of your life.

If You're Still Working: The Special Rules for Employer Coverage

If you're covered by a group health plan through your current employer, you have more flexibility. You can delay signing up for Medicare Part B without penalty as long as your employer has 20 or more employees and you're actively working. This is called creditable coverage, and it means your employer's plan is considered as good as or better than Medicare.

However, you must still sign up for Medicare Part A (hospital coverage) when you turn 65, even if you're working. Part A has no premium if you or your spouse paid Medicare taxes for at least 10 years, so there's no financial reason to delay it. You can delay Part B, but delaying Part A doesn't save you money and can create complications later.

Once you leave your job or lose your employer coverage, you have eight months to sign up for Part B without penalty. This eight-month window is called your Special Enrollment Period. If you miss this window, you will pay a penalty on your Part B premium for each year you delayed, and the penalty is permanent. The penalty is 10 percent of the standard Part B premium for each full 12 months you were may be able to access but not signed up.

If You're Already Receiving Social Security: Automatic Enrollment

If you're already receiving Social Security benefits before you turn 65, you will be signed up for Medicare automatically. Social Security will enroll you in Part A and Part B starting the month you turn 65, and you don't have to do anything. Your Medicare card will arrive in the mail about two weeks before your coverage starts.

If you don't want Part B coverage for some reason (for example, because you have employer coverage), you can decline it in writing before your coverage starts. However, declining Part B means you'll face a penalty if you sign up later, unless you have a valid reason for the delay. Most people should accept the automatic enrollment rather than risk a penalty.

If you're not yet receiving Social Security when you turn 65, you will need to sign up for Medicare yourself during your Initial Enrollment Period. You can do this even if you're not ready to claim Social Security benefits yet.

How to Sign Up: Three Ways to Enroll

You can sign up for Medicare in three ways: online, by phone, or in person. The fastest and most convenient way is online at Medicare.gov. You'll need your Social Security number, date of birth, and information about any current health coverage you have. The online process takes about 15 minutes, and you'll get a confirmation number right away.

You can also call 1-800-MEDICARE (1-800-633-4227) to sign up by phone. The line is open 24 hours a day, seven days a week. A representative will walk you through the process and answer questions about your specific situation. This is a good option if you're not comfortable using the internet or if you have questions that need a real person's answer.

Finally, you can sign up in person at your local Social Security office. You'll need to bring your Social Security card, proof of citizenship or legal residency, and proof of age. You can find your local office at ssa.gov or by calling 1-800-772-1213. In-person enrollment takes longer than online or phone, but some people prefer it.

What Happens If You Miss Your Enrollment Window

If you miss your Initial Enrollment Period and don't have a may have access to reason for the delay, you can still sign up for Medicare, but you will face a permanent penalty. For Part B, the penalty is 10 percent of the standard monthly premium for each full 12 months you were may be able to access but not enrolled. This penalty stays with you for life, even if you switch to a different plan.

For Part D (prescription drug coverage), the penalty is similar: 1 percent of the national average Part D premium for each month you were may be able to access but not enrolled. If you go 63 days or more without creditable drug coverage, you will owe this penalty when you finally sign up.

The only way to avoid these penalties is to have a may have access to reason for missing your enrollment window. may have access to reasons include losing employer coverage, moving out of your plan's service area, getting married or divorced, or having a significant drop in income. If you think you have a may have access to reason, you can contact Medicare to ask about a Special Enrollment Period that might let you sign up without penalty.

Part A Versus Part B: Which One Do You Need at 65

Medicare has different parts, and the age rules are slightly different for each. Part A (hospital insurance) covers inpatient hospital stays, skilled nursing facility care, hospice, and some home health services. You become may be able to access for Part A at 65 if you or your spouse paid Medicare taxes for at least 10 years. Part A has no monthly premium for most people, so there's no financial reason to delay it.

Part B (medical insurance) covers doctor visits, outpatient services, and some preventive care. It has a monthly premium that changes each year, and the premium is higher if you delay signing up past your Initial Enrollment Period. You become may be able to access for Part B at 65, and you should sign up during your Initial Enrollment Period unless you have employer coverage that counts as creditable.

Part D (prescription drug coverage) is optional, but you should sign up when you turn 65 or within three months of losing other drug coverage. If you go without creditable drug coverage for more than 63 days, you will pay a permanent penalty on your Part D premium.

Frequently Asked Questions

Can I sign up for Medicare before I turn 65?

Yes. You can sign up starting three months before your birthday month. For example, if you turn 65 in September, you can sign up starting in June. Your coverage can begin as early as the first day of your birthday month.

What if I'm still working and don't want Medicare yet?

If your employer has 20 or more employees and you're actively working, you can delay Part B without penalty. You should still sign up for Part A at 65 because it's free and has no downside. When you leave your job, you have eight months to sign up for Part B without penalty.

Do I have to sign up for Medicare at 65 if I'm not retiring?

You must sign up for Part A at 65 (it's free), but you can delay Part B if you have employer coverage. However, if you don't have employer coverage, you should sign up for Part B during your Initial Enrollment Period to avoid a permanent penalty.

What's the penalty for signing up late?

For Part B, you pay 10 percent of the standard monthly premium for each full 12 months you delayed. For Part D, you pay 1 percent of the national average Part D premium for each month you delayed. These penalties are permanent and stay with you for life.

Will I be automatically signed up for Medicare?

Only if you're already receiving Social Security benefits before you turn 65. If you're not yet receiving Social Security, you need to sign up yourself during your Initial Enrollment Period. You can sign up online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.