You must be 65 or older to enroll in Medicare, with rare exceptions for younger people with disabilities or end-stage renal disease

Medicare may be able to access begins the month you turn 65. You do not automatically receive it — you must sign up during your enrollment window, which opens three months before the month you turn 65 and closes three months after. If you miss this window, you may face a permanent penalty on your premiums.

The age 65 rule applies to most people. However, some people under 65 can enroll: those who have received Social Security Disability Insurance (SSDI) for 24 months, or those with end-stage renal disease (ESRD) or amyotrophic lateral sclerosis (ALS), regardless of age. These are the only medical exceptions.

Key Takeaways

  • You become may be able to access for Medicare the month you turn 65, but you must sign up during your enrollment window or face a permanent premium penalty.
  • Your enrollment window opens three months before you turn 65 and closes three months after — a total of seven months to sign up without penalty.
  • People under 65 who have received SSDI for 24 months, or who have ESRD or ALS, can enroll in Medicare regardless of age.
  • If you are still working at 65 and have health coverage through your employer, you may delay enrollment without penalty if your employer has 20 or more employees.

When your enrollment window opens and closes

Your Initial Enrollment Period (IEP) is seven months long. It starts three months before the month you turn 65 and ends three months after. For example, if you turn 65 in June, your window runs from March through September.

You can sign up online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office. Signing up early — even in the first month of your window — protects you from late penalties and ensures coverage starts on time.

If you miss your Initial Enrollment Period, you enter the General Enrollment Period, which runs January 1 through March 31 each year. Coverage under General Enrollment does not start until July 1 of that year, creating a gap. You will also owe a permanent 10 percent penalty on Part B premiums for each full year you were may be able to access but not enrolled.

How to sign up during your enrollment window

You have three ways to enroll. Online enrollment through Medicare.gov is fastest — you can complete it in 10 to 15 minutes if you have your Social Security number and birth date ready. You will receive a confirmation number when ready.

Phone enrollment through 1-800-MEDICARE takes longer but works if you prefer speaking to someone. Have your Social Security card and any current insurance information nearby. Wait times are shortest early in the morning on weekdays.

In-person enrollment at your local Social Security office guarantees a paper record and lets you ask questions face-to-face. Bring your Social Security card, birth certificate or passport, and proof of citizenship or legal residency. You can find your nearest office at ssa.gov/locator.

What happens if you are still working at 65

You do not have to sign up for Medicare at 65 if you are still employed and covered by your employer's health plan. However, this exception only applies if your employer has 20 or more employees. If your employer is smaller, you must enroll in Medicare when you turn 65 or face penalties.

If you delay enrollment because of employer coverage, you have an eight-month window after your employment ends or your coverage stops to sign up without penalty. This is called the Special Enrollment Period. You must sign up during this window — missing it means the same permanent penalties explore as if you had missed your Initial Enrollment Period.

When you do sign up after leaving your job, bring a letter from your employer stating your coverage dates and the number of employees. Medicare uses this to confirm you may have access to for penalty-free delayed enrollment.

Exceptions: Medicare before age 65

If you have received SSDI for 24 consecutive months, you become may be able to access for Medicare automatically. You do not need to explore separately — Social Security will enroll you. Your coverage begins the first day of the month after your 24-month waiting period ends. You will receive your Medicare card in the mail.

If you have end-stage renal disease (ESRD) — permanent kidney failure requiring dialysis or transplant — you can enroll in Medicare at any age. You must sign up within three months of starting dialysis treatment. If you have had a kidney transplant, you remain may be able to access for Medicare for three years after the transplant, even if the transplant fails.

If you have ALS (Lou Gehrig's disease), you become may be able to access for Medicare when ready upon diagnosis. You do not have to wait for SSDI approval. Contact Social Security to begin the enrollment process as soon as you receive your diagnosis.

Late enrollment penalties and how they work

If you do not sign up during your Initial Enrollment Period and you do not have an exception (like employer coverage or a Special Enrollment Period), you will owe a permanent penalty on Part B and Part D premiums.

The Part B penalty is 10 percent of the standard premium for each full year you were may be able to access but not enrolled. If the standard premium is $175 per month and you were may be able to access for three years without signing up, your penalty is 30 percent — an extra $52.50 per month for life. This penalty never goes away, even after you finally enroll.

The Part D penalty (for prescription drug coverage) works the same way: 1 percent of the national base premium for each month you were may be able to access without coverage. These penalties stack on top of your regular premiums and follow you as long as you have Medicare.

Frequently Asked Questions

Can I sign up for Medicare before I turn 65?

You can sign up three months before you turn 65 — that is the earliest your enrollment window opens. If you have SSDI, ESRD, or ALS, you may be may be able to access before 65 and should contact Social Security to confirm your enrollment date.

What if I turn 65 in the middle of the month?

Medicare may be able to access is based on the month you turn 65, not the specific date. If you turn 65 on any day in June, your enrollment window opens in March and closes in September. Coverage can begin as early as the first day of the month you turn 65 if you sign up early enough.

Do I lose my employer health insurance when I turn 65?

No. If you are still working and your employer has 20 or more employees, you can keep your employer coverage and delay Medicare without penalty. When you leave your job, you have eight months to sign up for Medicare without penalty.

What if I miss my enrollment window by a few weeks?

If you miss your Initial Enrollment Period, you cannot sign up again until the next General Enrollment Period (January 1 through March 31). Coverage will not start until July 1, and you will owe a permanent penalty on Part B premiums. Contact Social Security when ready to discuss your options.

Does my spouse's age affect when I can enroll?

No. Your enrollment is based only on your own age. Your spouse enrolls separately when they turn 65 or become may be able to access through SSDI, ESRD, or ALS. Each person has their own enrollment window and their own potential penalties.