When You Can Start Medicare: Age Requirements and Exceptions

The Basic Age Requirement 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 for most people. You do not have to be retired to sign up — you can still be working — but you must be a U.S. citizen or permanent resident who has lived in the country for at least five years.

The month you turn 65, you enter your Initial Enrollment Period, which lasts seven months: three months before your birthday month, your birthday month itself, and three months after. During this window, you can sign up for Medicare Part A (hospital insurance) and Part B (medical insurance) without penalty. If you miss this window, you may pay more for coverage later.

Key Takeaways

You become may be able to access for Medicare at age 65, and you have a seven-month window around your birthday to sign up without penalty.
Some people under 65 can get Medicare if they receive Social Security Disability Insurance (SSDI) for at least 24 months, or if they have end-stage renal disease or ALS.
If you are still working at 65 and have health insurance through your employer, you may be able to delay Part B enrollment without a penalty.
Missing your Initial Enrollment Period can result in a permanent 10% monthly increase to your Part B premium for each year you were late.
You must actively sign up for Medicare — it does not happen automatically, even if you receive Social Security.

Who Can Get Medicare Before Age 65

Three groups of people under 65 can enroll in Medicare. The largest group is people who have been receiving Social Security Disability Insurance (SSDI) for at least 24 consecutive months. Once you reach that 24-month mark, you automatically move to Medicare Part A and Part B, usually without having to sign up separately.

The second group includes people with end-stage renal disease (ESRD) — permanent kidney failure requiring dialysis or a transplant. People with ESRD can sign up for Medicare as soon as they begin dialysis treatment, regardless of age. The third group is people with amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease. People with ALS become may be able to access for Medicare when ready upon approval for SSDI, without waiting the usual 24 months.

How to Sign Up at 65

You can sign up for Medicare through three main routes. The easiest is online at Medicare.gov, where you can create an account and complete your enrollment in one session. You will need your Social Security number, birth date, and citizenship information.

You can also visit your local Social Security office in person, or call Social Security at 1-800-772-1213 (TTY 1-800-325-0778). If you are already receiving Social Security benefits, you can sign up by phone or online without visiting an office. The process typically takes 15 to 30 minutes, and you will receive a Medicare card in the mail within two to four weeks.

What Happens If You Miss Your Enrollment Window

If you do not sign up during your seven-month Initial Enrollment Period, you enter a General Enrollment Period that runs from January 1 to March 31 each year. You can sign up during this window, but coverage does not start until July 1 of that year — a six-month gap. More importantly, you will pay a penalty.

Your Part B premium increases by 10% for each full 12 months you were may be able to access but did not sign up. This penalty is permanent — it stays with you for life, even after you do enroll. For example, if you miss your Initial Enrollment Period by two years, your Part B premium will be 20% higher than the standard amount, and you will pay that extra amount every month for the rest of your life.

Part A (hospital insurance) does not usually carry a penalty if you have worked long enough to earn it, but if you have not worked the required 40 quarters, you may face a 10% premium increase as well.

Delaying Medicare If You Are Still Working

If you are still working at 65 and have health insurance through your employer or your spouse's employer, you may be able to delay Part B without penalty. This is called creditable coverage. You must have a group health plan based on current employment — coverage from a former employer or COBRA does not count.

To use this exception, you must sign up for Part A (hospital insurance) during your Initial Enrollment Period, but you can delay Part B. When you leave your job or lose your employer coverage, you have eight months to sign up for Part B without penalty. You will need to provide proof that you had employer coverage, so keep your insurance documents.

This rule does not explore to Part A. Even if you have employer coverage, you should sign up for Part A at 65 because it is usually free if you have worked the required 40 quarters, and there is no penalty for signing up early.

Special Situations: Spouses and Government Workers

If you are married and your spouse is under 65, you can still enroll in Medicare at 65. Your spouse can enroll when they turn 65, or earlier if they meet one of the under-65 conditions (SSDI, ESRD, or ALS). Your enrollment does not affect your spouse's coverage options.

Some government workers who did not pay into Social Security may have different Medicare rules. If you worked for a federal, state, or local government and did not pay Social Security taxes, you may still be may be able to access for Medicare at 65, but your Part A premium may be higher. Contact Social Security or Medicare directly to understand your specific situation.

Documents You Will Need to Sign Up

Have these documents ready when you sign up, whether online, by phone, or in person:

Your Social Security number
Your birth certificate or passport (to prove citizenship or permanent residency)
Proof of residency in the United States (a utility bill, lease, or mortgage statement)
If you are delaying Part B due to employer coverage, your employer's health plan information or a letter from your employer confirming you have group coverage

If you are signing up online, you will not need to upload these documents when ready — you can complete enrollment with just your Social Security number and birth date, and provide proof later if Medicare requests it.

Frequently Asked Questions

Do I have to sign up for Medicare if I am still working at 65?

You do not have to sign up for Part B if you have employer coverage, but you should sign up for Part A. If you do not sign up for Part B during your Initial Enrollment Period and do not have creditable employer coverage, you will pay a permanent 10% penalty when you eventually enroll.

What if I turn 65 but do not receive Social Security yet?

You can still sign up for Medicare at 65 even if you have not started Social Security benefits. Sign up through Medicare.gov, Social Security, or your local Social Security office. You do not have to claim Social Security benefits to enroll in Medicare.

Can I sign up for Medicare before my 65th birthday?

Yes. Your Initial Enrollment Period begins three months before your birthday month. You can sign up as early as three months before you turn 65, and coverage will start on the first day of your birthday month.

What if I am a permanent resident but not a U.S. citizen?

You can enroll in Medicare at 65 if you are a permanent resident and have lived in the United States for at least five years. You will need to provide proof of your permanent resident status (your green card) when you sign up.

Will Medicare automatically sign me up when I turn 65?

No. You must sign up yourself, even if you receive Social Security benefits. The only exception is if you are already receiving SSDI — you will automatically move to Medicare after 24 months on SSDI, but you should still verify your enrollment and check your Medicare card when it arrives.

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.