When You Become Eligible for Medicare Based on Age

The Basic Age Rule for Medicare

You become may be able to access for Medicare at age 65, regardless of your work history or income. This is the standard entry point, and it applies to U.S. citizens and permanent residents who have lived in the country for at least five years. You do not have to wait until you retire — Medicare may be able to access and retirement are separate decisions.

The month you turn 65, you enter your Initial Enrollment Period, a seven-month window that starts three months before your birthday month and ends three months after it. During this window, you can sign up for Medicare Part A (hospital insurance) and Part B (medical insurance) without penalty. Missing this window can cost you more in premiums for the rest of your life, so the timing matters.

If you are already receiving Social Security benefits when you turn 65, you will be enrolled in Medicare automatically. If you are not yet taking Social Security, you must sign up for Medicare yourself through Medicare.gov, by phone, or at your local Social Security office.

Key Takeaways

You are may be able to access for Medicare the month you turn 65, and you have a seven-month enrollment window centered on your birthday month to sign up without penalty.
If you are receiving Social Security at 65, Medicare enrollment happens automatically; otherwise, you must sign up yourself.
Delaying enrollment past your Initial Enrollment Period can add a permanent surcharge to your Part B and Part D premiums.
You can sign up online at Medicare.gov, by calling 1-800-MEDICARE, or in person at your local Social Security office.
Some people under 65 may be may be able to access for Medicare if they receive Social Security Disability Insurance (SSDI) or have end-stage renal disease or ALS.

What Happens If You Miss Your Enrollment Window

If you do not sign up during your Initial Enrollment Period and you do not have other may have access to coverage (such as employer health insurance), you will face a late enrollment penalty. For Part B, this penalty is 10 percent of the standard premium for each full year you were may be able to access but not enrolled. That surcharge stays on your premium for as long as you have Medicare.

The same rule applies to Part D (prescription drug coverage). If you go without creditable drug coverage for more than 63 days in a row, you will owe a penalty when you eventually sign up. The penalty is calculated based on how long you went without coverage.

There are narrow exceptions: if you had employer coverage or were covered under a spouse's plan, you may not owe a penalty. You will need to show proof of that coverage when you enroll. If you are unsure whether your coverage counts as creditable, ask your employer or your insurance company before your enrollment window closes.

Enrolling Before Age 65 If You may have access to Early

Some people under 65 can enroll in Medicare. If you have been receiving Social Security Disability Insurance (SSDI) for 24 months, you become may be able to access for Medicare at any age. The 24-month waiting period starts from the month you were approved for SSDI, not from when you applied.

If you have end-stage renal disease (ESRD) — permanent kidney failure requiring dialysis or a transplant — you can enroll in Medicare regardless of age. You have a four-month enrollment window: two months before the month dialysis starts (or the month of transplant) and two months after. If you miss this window, you can enroll during the general enrollment period (January 1 to March 31 each year), but you may face a late enrollment penalty.

If you have ALS (amyotrophic lateral sclerosis), you are may be able to access for Medicare when ready upon approval for SSDI, with no 24-month waiting period. Your enrollment window is the same as for other SSDI beneficiaries.

How to Sign Up During Your Enrollment Period

The easiest method is online at Medicare.gov. You will need your Social Security number, proof of citizenship or permanent residency, and information about any current health coverage. The online process takes about 15 minutes and you receive confirmation when ready.

You can also call 1-800-MEDICARE (1-800-633-4227) to speak with a representative. They can answer questions about your specific situation and enroll you over the phone. The line is open 24 hours a day, seven days a week. Have your Social Security number and any insurance documents nearby when you call.

A third option is to visit your local Social Security office in person. You will need to bring your Social Security card, proof of citizenship (passport, birth certificate, or naturalization papers), and proof of residency (a recent utility bill or lease). Staff can enroll you on the spot, though wait times vary by location.

Understanding Part A and Part B Enrollment

Part A (hospital insurance) covers inpatient hospital stays, skilled nursing facility care, hospice, and some home health services. Most people do not pay a premium for Part A if they or their spouse paid Medicare taxes for at least 10 years. If you do not meet this requirement, you can still enroll, but you will pay a monthly premium.

Part B (medical insurance) covers doctor visits, outpatient care, medical equipment, and preventive services. Everyone pays a monthly premium for Part B. The standard premium in 2024 is $174.70 per month, though it varies based on your income. Higher earners pay more through an income-related adjustment.

You can enroll in Part A and Part B at the same time, or you can enroll in Part A only and delay Part B if you are still covered by employer health insurance. However, if you delay Part B past your Initial Enrollment Period without creditable coverage, you will owe a late enrollment penalty.

Special Enrollment Periods and Life Changes

If you miss your Initial Enrollment Period but experience a may have access to life event, you may be able to enroll during a Special Enrollment Period without penalty. may have access to events include losing employer coverage, moving out of your plan's service area, or having a change in your Medicaid status.

You must enroll within two months of the event that triggered the Special Enrollment Period. For example, if you lose employer coverage on June 15, you have until August 15 to sign up for Medicare without penalty. You will need to provide proof of the event — such as a letter from your employer stating the coverage ended.

If you are still working and covered by your employer's health plan at 65, you can delay Part B enrollment without penalty as long as your employer has at least 20 employees. When you finally leave that job or lose the coverage, you have eight months to enroll in Part B without penalty.

Frequently Asked Questions

Can I sign up for Medicare before I turn 65?

You can sign up during the three months before your 65th birthday as part of your Initial Enrollment Period. You cannot sign up earlier unless you may have access to under a disability or ESRD exception. If you have SSDI, you are automatically enrolled in Medicare after 24 months of receiving benefits.

What if I am still working at 65 and have health insurance through my job?

You can delay enrolling in Part B without penalty as long as your employer has at least 20 employees and you are actively working. You must enroll within eight months of leaving the job or losing coverage. Part A enrollment is still recommended because it has no premium for most people.

Do I have to enroll in Part D when I turn 65?

Part D (prescription drug coverage) is optional, but delaying enrollment without creditable drug coverage can result in a permanent penalty. If you have coverage through an employer or union that is as good as Medicare's, you may not need Part D. Ask your plan administrator whether your coverage is creditable.

What happens if I turn 65 while living outside the United States?

You can still enroll in Medicare, but Part A and Part B coverage outside the U.S. is limited. Medicare generally does not pay for care received outside the country except in very specific situations. You should still enroll to avoid late penalties, but you may want to explore supplemental or international health insurance options.

Can my spouse enroll in Medicare based on my work record?

Yes. If you have worked and paid Medicare taxes for at least 10 years, your spouse can enroll in Part A at 65 based on your record, even if they did not work. Your spouse will still need to enroll in Part B separately and will pay the Part B premium. This is different from Social Security spousal benefits and requires a separate enrollment.

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.