The Basic Age and Citizenship Rules

You become may be able to access for Medicare at age 65, regardless of your work history or income — as long as you are a U.S. citizen or permanent resident who has lived in the country for at least five consecutive years. You do not have to be retired to enroll; Medicare may be able to access and retirement are separate decisions.

If you were born on the first of the month, Medicare considers you one month older for enrollment purposes. This matters because it shifts your enrollment window slightly earlier. Your birthday month is when your coverage can start, not the month after.

Permanent residents (green card holders) must have lived in the United States for five years before they become may be able to access. The five years do not have to be consecutive if you left and returned, but you must have permanent resident status for that entire period.

Key Takeaways

  • You become may be able to access for Medicare at age 65 if you are a U.S. citizen or permanent resident who has lived here for at least five consecutive years.
  • You can enroll during your Initial Enrollment Period, which runs three months before your 65th birthday, the month you turn 65, and three months after — a seven-month window.
  • If you delay enrollment past your Initial Enrollment Period without a valid reason, you may pay permanently higher premiums for Part B and Part D coverage.
  • You may become may be able to access before age 65 if you receive Social Security Disability Insurance (SSDI) for 24 months or have end-stage renal disease or ALS.

When Your Enrollment Window Opens

Your Initial Enrollment Period is a seven-month window: it starts three months before the month you turn 65, includes the month you turn 65, and extends three months after. For example, if you turn 65 in June, your window opens in March and closes in September.

You should enroll during this window even if you do not plan to use Medicare right away. Waiting past this period triggers a late enrollment penalty — a permanent increase to your Part B and Part D premiums that lasts as long as you have coverage. The penalty is calculated as a percentage of the standard premium for each month you were may be able to access but not enrolled.

There is one major exception: if you or your spouse are still working and covered by an employer health plan, you may be able to delay enrollment without penalty. This is called creditable coverage. You will need to show Medicare that your employer plan is at least as good as Medicare coverage. When you do enroll after leaving that job, you have an eight-month window to sign up without penalty.

may be able to access Before Age 65

You can enroll in Medicare before 65 if you have received Social Security Disability Insurance (SSDI) for 24 consecutive months. The 24 months starts from when your disability benefits began, not from when you applied. Once you have been on SSDI for two years, you become may be able to access for Medicare automatically — you do not have to explore separately.

You also become may be able to access before 65 if you have been diagnosed with end-stage renal disease (ESRD) — permanent kidney failure requiring dialysis or a transplant. You can enroll in Medicare as soon as you start dialysis or receive a transplant, even if you are still working. The same applies if you have amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease — you become may be able to access when ready upon diagnosis, with no waiting period.

How to Enroll During Your may be able to access Window

You can enroll through three routes: online at Medicare.gov, by phone at 1-800-MEDICARE (1-800-633-4227), or in person at your local Social Security office. Online enrollment is usually the fastest — you can complete it in 10 to 15 minutes if you have your Social Security number and basic health information ready.

If you are already receiving Social Security benefits when you turn 65, you may be enrolled automatically in Medicare Part A and Part B. Check your Social Security account online or call Social Security to confirm. If you are not yet receiving benefits, you will need to enroll yourself; Social Security does not enroll you automatically.

Have your birth certificate, proof of citizenship or permanent resident status, and information about any current health coverage available when you enroll. If you are enrolling due to ESRD or ALS, you will need medical documentation from your doctor.

What Happens If You Miss Your Enrollment Window

If you do not enroll during your Initial Enrollment Period and do not have creditable coverage through an employer plan, you will face a late enrollment penalty on Part B and Part D premiums. The penalty is 10 percent of the standard Part B premium for each full 12-month period you were may be able to access but not enrolled. For Part D, the penalty is 1 percent of the national average premium for each month you were not enrolled.

These penalties are permanent — they do not go away even after you finally enroll. You can still enroll later during the General Enrollment Period (January 1 through March 31 each year), but your coverage will not start until July 1 of that year, and the penalty will explore.

The only way to avoid the penalty after missing your window is to prove you had creditable coverage. This means you must have had health insurance through an employer, COBRA, or a similar plan that is at least as comprehensive as Medicare. You will need to provide documentation from your former employer or insurance company.

Special Situations That Affect Your Enrollment

If you are still working at age 65 and your employer has 20 or more employees, you may not need to enroll in Medicare Part B right away. Your employer's health plan is considered primary, and Medicare is secondary. You can delay Part B enrollment without penalty as long as you enroll within eight months of leaving that job or losing the coverage.

If you are a federal employee, railroad retiree, or covered under a specific government health plan, your enrollment rules may differ slightly. Contact your benefits administrator to confirm your may be able to access date and enrollment important date.

If you are receiving veterans' benefits, you may have additional coverage options outside Medicare. Veterans can use VA health services alongside Medicare, but you will still need to enroll in Medicare at 65 to avoid penalties, even if you do not plan to use it when ready.

Frequently Asked Questions

Can I enroll in Medicare before my 65th birthday?

Yes, but only during your Initial Enrollment Period, which starts three months before you turn 65. You cannot enroll earlier than that unless you may have access to for early may be able to access due to SSDI (after 24 months), ESRD, or ALS. If you are still working and covered by an employer plan, you can wait until after you leave that job.

What if I was born on the first of the month?

Medicare treats you as one month older for enrollment purposes. If you were born on the first, your Initial Enrollment Period starts four months before your birthday month instead of three. Contact Medicare directly to confirm your exact enrollment window.

Do I have to enroll in Part B if I am still working?

If your employer has 20 or more employees and you are covered by their health plan, you can delay Part B without penalty. You have eight months after you leave the job or lose coverage to enroll. Part A (hospital insurance) has different rules — you may want to enroll in Part A even if you delay Part B.

What counts as creditable coverage for delaying enrollment?

Creditable coverage is health insurance from an employer with 20 or more employees, COBRA continuation coverage, or certain government plans that is at least as comprehensive as Medicare. Coverage from a spouse's employer plan also counts. You will need written proof from your employer or insurance company showing the dates you were covered.

Can I get my late enrollment penalty waived?

Late enrollment penalties are rarely waived. The only common exception is if you can prove you had creditable coverage during the time you were not enrolled in Medicare. You must provide documentation from your former employer or insurance company. Contact Medicare to discuss your specific situation.