When You Can Sign Up for Medicare: Age and Timing Rules

You can sign up for Medicare at 65, or earlier if you have a disability or end-stage renal disease

Medicare may be able to access starts at age 65 for most people. You do not have to wait until your birthday month — you can sign up during the three months before you turn 65, the month you turn 65, or the three months after. That seven-month window is called your Initial Enrollment Period.

If you sign up before your 65th birthday, your coverage typically begins on the first day of the month you turn 65. If you sign up after your birthday, there may be a delay — sometimes coverage does not start until a month or two later, depending on when exactly you enroll.

You do not automatically get Medicare at 65. You have to sign up yourself, either online, by phone, by mail, or in person at a Social Security office. If you are already receiving Social Security benefits, you may be enrolled automatically, but it is worth confirming.

Key Takeaways

You can sign up for Medicare starting three months before you turn 65, during the month you turn 65, or up to three months after — a total window of seven months.
If you sign up before your 65th birthday, coverage usually starts the first of the month you turn 65; if you sign up after, there may be a one- or two-month delay.
You are not automatically enrolled in Medicare at 65 unless you are already receiving Social Security; you must sign up yourself.
If you have a disability or end-stage renal disease, you may be able to sign up before 65; the rules depend on your specific situation.
Missing your Initial Enrollment Period can result in a permanent penalty on your premiums, so signing up on time matters.

Signing up before 65 if you have a disability

If you receive Social Security Disability Insurance (SSDI) or Railroad Retirement Board disability benefits, you become may be able to access for Medicare after you have been receiving those benefits for 24 months. You do not have to wait until 65. Medicare will cover you automatically once those 24 months are up, so you do not need to sign up separately — but you should still verify that your coverage started.

If you have end-stage renal disease (ESRD) — permanent kidney failure requiring dialysis or a transplant — you can sign up for Medicare regardless of age. You have a special enrollment period that begins the month your kidney disease is diagnosed, and coverage can start as early as the first day of the month after you are diagnosed or begin dialysis, whichever comes first.

If you have ALS (amyotrophic lateral sclerosis), you become may be able to access for Medicare when ready upon approval for SSDI, without waiting the usual 24 months. You should receive notice from Social Security about your Medicare coverage.

What happens if you miss your Initial Enrollment Period

If you do not sign up during your seven-month window around your 65th birthday, you can still sign up later, but you may face a late enrollment penalty. This penalty is a permanent increase to your monthly premium for Part B (doctor and outpatient care) and Part D (prescription drugs). The penalty amount depends on how long you went without coverage.

For every 12 months you delayed Part B enrollment after your Initial Enrollment Period ended, your premium increases by 10 percent. For Part D, the penalty is roughly 1 percent of the national average premium for every month you were without coverage. These penalties stay with you for as long as you have Medicare.

There are some exceptions: if you had health insurance through an employer while you were working, or through your spouse's employer, you may not face a penalty. You would need to show proof of that coverage when you do sign up. This is called creditable coverage, and it protects you from the penalty if you enroll within eight months of losing that job-based insurance.

How to sign up for Medicare

You can sign up online at Medicare.gov, by phone at 1-800-MEDICARE (1-800-633-4227), by mail using the process form, or in person at your local Social Security office. Online is usually the fastest option if you are comfortable with it.

You will need your Social Security number, proof of citizenship or legal residency (such as a birth certificate or passport), and proof of age. If you are signing up for Part A and Part B, that is usually all you need. If you are also choosing a Part D plan (prescription drug coverage), you will want to know what medications you take so you can pick a plan that covers them.

The Social Security Administration handles enrollment for Part A and Part B. Private insurance companies handle Part D and Part C (Medicare Advantage) enrollment, though you can see all available plans and compare them at Medicare.gov before you choose.

Special enrollment periods if you miss the important date

Even if you miss your Initial Enrollment Period, you may have a second chance to sign up without a penalty if you had a may have access to life event. These include losing job-based health insurance, moving to a new state, getting married or divorced, or having a significant change in income.

You typically have 60 days from the may have access to event to sign up. For example, if you retire and lose your employer health insurance at age 67, you have 60 days from the date your coverage ends to enroll in Medicare Part B without a penalty. You will need to provide proof of the event — a termination letter from your employer, a divorce decree, or a notice of move, for instance.

If you are not sure whether your situation qualifies, call 1-800-MEDICARE and describe what happened. The representative can tell you whether you have a special enrollment period available.

Timing your sign-up if you are still working at 65

If you are still working and covered by your employer's health plan at 65, you do not have to sign up for Medicare right away. You can delay Part B enrollment without a penalty as long as your employer has 20 or more employees and you are actively working. This protection is called group health plan coverage.

However, you should still sign up for Part A (hospital insurance) at 65, even if you delay Part B. Part A is usually free if you or your spouse paid Medicare taxes while working, and there is no penalty for signing up. Part B is where the penalty applies if you delay.

When you do leave your job or lose that employer coverage, you have eight months to sign up for Part B without a penalty. Keep the termination letter or coverage end date from your employer — you will need it to prove you had creditable coverage.

Medicare coverage for non-citizens and people with immigration status

To sign up for Medicare, you must be a U.S. citizen or a permanent resident (green card holder) who has lived in the United States for at least five years. If you are a permanent resident, you will need to provide proof of your status when you enroll.

If you are not a citizen or permanent resident, you may not be able to get Medicare, but you may have other options for health coverage depending on your immigration status and where you live. Contact your state health department or a local community health center to learn what is available to you.

Frequently Asked Questions

Can I sign up for Medicare before I turn 65?

Yes, you can sign up starting three months before your 65th birthday. If you have a disability and have been receiving SSDI for 24 months, or if you have end-stage renal disease, you may be able to sign up before 65 regardless of age. Call 1-800-MEDICARE to discuss your specific situation.

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

You should still sign up for Part A at 65 because it is usually free and has no penalty for delaying. You can delay Part B without penalty as long as your employer has 20 or more employees and you are actively working. When you leave that job, you have eight months to sign up for Part B.

How much does it cost to sign up for Medicare?

There is no cost to sign up. However, Medicare has monthly premiums for Part B and Part D, and costs vary depending on your income and the plans you choose. You can see current premium amounts at Medicare.gov.

What if I miss the important date and do not have creditable coverage?

You can still sign up, but you will face a permanent penalty on your Part B and Part D premiums. The penalty is 10 percent per year of delay for Part B and roughly 1 percent per month for Part D. These penalties stay with you for life, so signing up as soon as you realize you missed the important date is important.

Do I need to sign up for Part D at the same time as Part A and Part B?

No. You can sign up for Part A and Part B at 65 and add Part D later if you do not take prescription medications. However, if you do take medications and you delay Part D enrollment past your Initial Enrollment Period, you will face a penalty. If you are unsure, it is safer to sign up for Part D at 65 even if you do not use it yet.

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.