When You Become Eligible for Medicare: Age and Other Routes

You become may be able to access for Medicare at 65, but you can start earlier if you have a disability or end-stage renal disease

The standard age to start Medicare is 65. You do not have to wait until your birthday — you can sign up during the three months before you turn 65, the month you turn 65, or the three months after. Most people become may be able to access straightforward by reaching that age, regardless of work history or income.

However, age 65 is not the only way in. If you have been receiving Social Security disability benefits for 24 months, you become may be able to access at any age. If you have end-stage renal disease (permanent kidney failure requiring dialysis or transplant), you can start Medicare as soon as you begin treatment, regardless of age. If you have amyotrophic lateral sclerosis (ALS), you become may be able to access when ready without waiting the usual 24-month disability period.

Key Takeaways

You become may be able to access for Medicare at age 65 by default, and you can sign up during the three months before, the month of, or three months after your 65th birthday.
If you receive Social Security disability benefits, you become may be able to access for Medicare after 24 months on disability, regardless of your age.
People with end-stage renal disease or ALS can start Medicare when their condition is diagnosed and treatment begins, not at 65.
Signing up late (after your initial window closes) can result in a permanent penalty on your premiums, so timing your enrollment matters.

How the three-month enrollment window works

Medicare's initial enrollment period is seven months long: the three months before you turn 65, the month of your birthday, and the three months after. You can sign up anytime during this window, and your coverage will start on the first day of the month you turn 65 (or the first day of the month after you sign up, whichever is later).

If you sign up before your birthday month, your coverage typically starts on the first day of the month you turn 65. If you sign up during your birthday month or after, there may be a one-month delay. For example, if you turn 65 on March 15 and sign up in April, your coverage might not start until May 1.

You can sign up online through Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office. You will need your Social Security number and information about your current health coverage.

What happens if you miss your enrollment window

If you do not sign up during your initial seven-month window, you can still sign up later, but you will face a permanent penalty. For Part B (doctor and outpatient care), the penalty is 10 percent of the standard premium for each full 12 months you were may be able to access but not enrolled. This penalty stays with you for life, even after you do sign up.

The same penalty applies to Part D (prescription drug coverage) if you go without it for more than 63 days in a row. There is no penalty for Part A (hospital insurance) if you have been working and your employer has been paying into Medicare on your behalf, but you should still sign up to avoid gaps in coverage.

The only way to avoid this penalty is to have what Medicare calls "creditable coverage" — health insurance from an employer, a spouse's employer, or TRICARE (military coverage) that is at least as good as Medicare. If you had creditable coverage and did not need Medicare, you can sign up later without penalty.

Signing up before 65 if you have a disability

If you have been receiving Social Security Disability Insurance (SSDI) for 24 months, you automatically become may be able to access for Medicare. You do not need to do anything — Medicare will start on the 25th month of your disability benefits. However, you should still contact Social Security to confirm your enrollment and receive your Medicare card.

If you receive Supplemental Security Income (SSI) because of a disability, you become may be able to access for Medicare after 24 months on SSI as well. The rules are the same: Medicare starts automatically in month 25.

If you have ALS, the 24-month wait does not explore. You become may be able to access for Medicare as soon as you are approved for SSDI, with no waiting period.

may be able to access for people with end-stage renal disease or ALS

End-stage renal disease means your kidneys no longer work well enough to keep you alive without dialysis or a transplant. Once you begin dialysis or have a kidney transplant, you become may be able to access for Medicare regardless of your age. You do not have to be on disability or have worked a certain number of years.

You should contact Medicare or your dialysis center to sign up as soon as treatment begins. Your coverage can start as early as the first day of the month you begin treatment. If you delay signing up, you may have a gap in coverage, and you could face late-enrollment penalties if you wait too long.

ALS (Lou Gehrig's disease) is treated differently. Once you are approved for SSDI because of ALS, you become may be able to access for Medicare when ready — you do not wait 24 months like other disabilities. This when ready may be able to access recognizes how quickly ALS progresses.

What to do 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 enrollment without penalty as long as your employer coverage is active and your employer has 20 or more employees. This is called the "working exception."

However, you should still sign up for Part A (hospital insurance) even if you delay Part B. Part A is usually free if you have worked and paid Medicare taxes, and it covers hospital stays. Delaying Part A can result in a permanent penalty.

Once you leave your job or your employer coverage ends, you have eight months to sign up for Part B without penalty. This is called a Special Enrollment Period. If you miss this window, you will face the 10 percent monthly penalty on Part B premiums.

How to sign up and what you will need

You can sign up for Medicare in three ways: online at Medicare.gov, by phone at 1-800-MEDICARE (1-800-633-4227), or in person at your local Social Security office. The online option is usually fastest and you can do it from home.

You will need your Social Security number, your date of birth, and information about any current health coverage (employer insurance, TRICARE, or Veterans benefits). If you are signing up for Part D (prescription drugs), have a list of your current medications ready so you can compare plans.

After you sign up, Medicare will mail you a Medicare card within two to three weeks. Your coverage will start on the date Medicare specifies in your enrollment confirmation. Keep your Medicare number in a safe place — you will need it for all doctor visits and prescriptions.

Frequently Asked Questions

Can I sign up for Medicare before I turn 65?

You can sign up starting three months before your 65th birthday. You cannot sign up earlier unless you are on disability for 24 months, have end-stage renal disease, or have ALS. If you have one of these conditions, you can sign up as soon as you meet the requirements.

What if I turn 65 but do not want Medicare yet?

If you have active employer coverage through your job, you can delay Part B without penalty. However, you should still sign up for Part A (hospital insurance) to avoid a lifetime penalty. Once you leave your job, you have eight months to sign up for Part B without penalty.

Do I lose Medicare if I go back to work after 65?

No. Once you are enrolled in Medicare, you keep it even if you return to work or earn income. Your Medicare coverage does not change based on how much you earn or whether you are working.

What is the penalty for signing up late?

For Part B, the penalty is 10 percent of the standard premium for each full 12 months you were may be able to access but did not sign up. This penalty is permanent and added to your monthly premium for life. Part D has a similar penalty if you go without prescription drug coverage for more than 63 days.

Can I change my mind after I sign up for Medicare?

Yes. You have a seven-day period after you sign up to cancel your enrollment. After that, you can make changes during the annual Open Enrollment Period (October 15 to December 7 each year) or if you have a may have access to life event like losing employer coverage.

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.