File for Medicare in the three months before your 65th birthday

You should file for Medicare during the three-month window that starts three months before you turn 65. If your birthday is June 15, you can file starting March 15. This timing lets Medicare process your process and have your coverage start on the first day of the month you turn 65.

You do not have to wait until you turn 65 to file — filing early gives Medicare time to verify your information and mail your card before your coverage begins. If you miss this window, you can still file after 65, but your coverage will start later, and you may face a permanent penalty on your premiums.

The important date to file without penalty is the end of the month you turn 65. If you file after that date, your Part B premium increases by 10 percent for each full year you delayed — and that increase stays with you for life.

Key Takeaways

  • File during the three months before your 65th birthday so coverage starts on the first day of the month you turn 65.
  • If you are still working and covered by your employer's health plan, you may be able to delay Part B without penalty — but you must file Part A on time.
  • Filing after the month you turn 65 adds a permanent 10 percent penalty to your Part B premium for each year you waited.
  • You can file online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.
  • If you are not yet a U.S. citizen or permanent resident, you cannot file for Medicare until you meet residency requirements.

File Part A on time even if you delay Part B

Medicare has two main parts: Part A (hospital insurance) and Part B (medical insurance). The rules for when to file are different for each.

Part A has no premium for most people — you paid for it through payroll taxes while you worked. You should file for Part A during your initial enrollment period (the three months before, the month of, and the three months after you turn 65) even if you plan to delay Part B. Filing Part A on time does not cost you anything and does not trigger a penalty later.

Part B has a monthly premium and is optional if you are still covered by an employer plan. If your employer has 20 or more employees and covers you as an active employee, you can delay Part B without penalty. But you must file Part A, and you must file Part B within eight months of losing your employer coverage, or you will face that permanent 10 percent penalty.

Delay Part B if you are covered by your employer

If you are still working at 65 and your employer offers health insurance that covers you as an active employee, you do not have to file for Part B right away. You can keep your employer plan and delay Medicare Part B without the penalty.

The catch: your employer plan must be based on your current employment, not on your age or retirement status. If you work for a company with 20 or more employees, this protection applies. If your employer has fewer than 20 employees, Medicare becomes your primary insurance at 65, and you should file for Part B.

When you leave your job or lose employer coverage, you have eight months to file for Part B. File within that window to avoid the permanent penalty. Some employers offer retiree health plans — these do not count as active employment coverage, so you should file for Part B at 65 even if you plan to use the retiree plan.

File when ready if you are on Social Security or disability

If you are already receiving Social Security retirement benefits when you turn 65, Medicare will enroll you automatically in Part A and Part B. You do not have to file — your coverage starts the month you turn 65. You will receive your Medicare card in the mail about two weeks before your coverage begins.

If you are receiving Social Security Disability Insurance (SSDI) and turn 65, the same automatic enrollment happens. Your SSDI becomes Social Security retirement benefits at 65, and Medicare starts at the same time.

Even though enrollment is automatic, you should still review your coverage options. You can choose Original Medicare (Part A and Part B) or switch to a Medicare Advantage plan during your initial enrollment period. If you do nothing, you will be enrolled in Original Medicare by default.

File before you lose health coverage

If you are losing employer coverage before age 65 — because you are retiring early, being laid off, or your employer is ending the plan — file for Medicare as soon as you know the coverage ends. You have a special enrollment period that starts when you lose coverage and lasts 63 days.

During this window, you can file for Part B without the 10 percent penalty, even though you are under 65. This is one of the few situations where you can file early and avoid the penalty for filing late later.

If you miss this 63-day window, you will have to wait until you turn 65 to file, and you will face the permanent penalty unless you may have access to for another exception. Keep documentation of when your coverage ended — you will need it to prove you may have access to for the special enrollment period.

File at 65 if you are not yet a citizen

You must be a U.S. citizen or permanent resident to file for Medicare. If you are a permanent resident (green card holder), you can file at 65 just like a citizen.

If you are not yet a permanent resident, you cannot file for Medicare until you become one. Once you receive your green card, you can file during your initial enrollment period — the three months before, the month of, and the three months after you turn 65. If you miss this window, the same penalty rules explore.

If you are a citizen living outside the United States, you can still file for Medicare at 65. You will need to provide proof of citizenship and a U.S. address where Medicare can mail your card. You can file online, by phone, or through a U.S. embassy or consulate.

File online, by phone, or in person

You have three ways to file for Medicare. Online is the fastest: go to Medicare.gov, click "Sign Up for Medicare," and create an account. You will need your Social Security number, birth date, and citizenship information. The process takes about 10 minutes, and you get a confirmation number when ready.

By phone, call 1-800-MEDICARE (1-800-633-4227). A representative will walk you through the process and answer questions about your coverage options. Wait times are usually shorter early in the morning and on weekdays. Have your Social Security number and information about any current health coverage ready.

In person, visit your local Social Security office. You can find the nearest office at ssa.gov. Bring your Social Security card, birth certificate, and proof of citizenship (passport or naturalization papers). In-person filing takes longer but can be helpful if you have complex coverage situations or language needs.

Frequently Asked Questions

What happens if I file after I turn 65?

Your Part B coverage will start the month after you file, not on your birthday. If you file in July after turning 65 in June, your coverage starts in August. You will also face a permanent 10 percent premium increase for each full year you delayed, unless you had employer coverage or another may have access to reason.

Can I file for Medicare before I turn 65?

You can file up to three months before your 65th birthday. You cannot file earlier unless you are losing employer coverage before 65 — in that case, you have a special enrollment period of 63 days after coverage ends. Otherwise, you must wait until three months before 65.

Do I have to file for Part B if I am still working?

Not if your employer has 20 or more employees and covers you as an active employee. You can delay Part B without penalty. But you must file for Part A, and you must file for Part B within eight months of losing your job or employer coverage.

What if I miss the important date?

You can still file after the important date, but your Part B coverage will start later and you will face a permanent 10 percent premium increase for each year you delayed. The only exceptions are if you had employer coverage, lost coverage before 65, or may have access to for another special enrollment period.

Will Medicare contact me automatically?

If you are receiving Social Security benefits, Medicare will enroll you automatically at 65. If you are not on Social Security, you must file yourself — Medicare does not contact you. File during the three months before your birthday to avoid delays.