You are not automatically enrolled in Medicare at 65 — you must sign up yourself

Medicare does not enroll you on your birthday. You have to take action, and the timing matters. If you wait past your important date, you may pay a penalty for the rest of your life, even if you eventually sign up. The important date is based on your 65th birthday month, not the exact date.

Most people become may be able to access for Medicare the first day of the month they turn 65. If you were born on any day in January, your coverage can start January 1. If you were born on any day in February, your coverage can start February 1. You have a window to sign up: you can enroll starting three months before the month you turn 65, and you have until three months after. That is a seven-month window total.

If you miss that window and do not have other coverage, you will owe a late enrollment penalty on top of your regular premiums. The penalty is permanent — it stays with you even after you finally sign up. The only way to avoid it is to have had creditable coverage (like an employer plan) during the time you were not enrolled.

Key Takeaways

  • You must sign up for Medicare yourself; the government does not enroll you automatically at 65.
  • Your enrollment window opens three months before your 65th birthday month and closes three months after — a total of seven months.
  • If you miss the important date and have no other coverage, you will pay a permanent penalty added to your premiums for life.
  • You can sign up online at Medicare.gov, by phone at 1-800-MEDICARE, or in person at your local Social Security office.
  • If you are still working and covered by your employer's health plan, you may be able to delay Part B enrollment without penalty.

When your enrollment window opens and closes

Your Initial Enrollment Period 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, you can enroll starting in March and must enroll by September 30.

The exact dates matter because Medicare coverage starts on the first day of a month. If you enroll during the three months before your birthday month, your coverage can start the month you turn 65. If you enroll in the month you turn 65 or after, your coverage starts the following month. If you enroll in the third month after (the last month of your window), your coverage does not start until two months later.

This timing affects when you need to act. If you want coverage to begin the month you turn 65, you should enroll by the end of the month before you turn 65. If you miss that important date but enroll within your seven-month window, you will still be covered, but it will start later.

What happens if you miss your enrollment important date

If you do not sign up during your seven-month Initial Enrollment Period and you do not have other may have access to coverage, you will owe a late enrollment penalty. This penalty is a percentage added to your Part B and Part D premiums, and it stays with you permanently.

The Part B penalty is 10 percent of the standard premium for each full 12 months you were may be able to access but not enrolled. If you were may be able to access for three years and did not sign up, your penalty is 30 percent of the standard premium, added to every bill for the rest of your life. The Part D penalty works the same way for prescription drug coverage.

The only way to avoid this penalty is if you had creditable coverage — health insurance through an employer, a spouse's employer, TRICARE, the VA, or certain other sources — during the time you were not enrolled in Medicare. You will need to show proof of that coverage when you eventually sign up. If you had a gap of 63 days or more without any coverage, the penalty applies to that gap.

How to sign up for Medicare

You have three ways to enroll: online, by phone, or in person. The online option is the fastest and available 24 hours a day.

To sign up online, go to Medicare.gov and look for the "Sign Up for Medicare" section. You will need your Social Security number, your birth date, and information about any current health coverage. The system will walk you through choosing Part A (hospital insurance) and Part B (medical insurance). You can also choose a Part D plan (prescription drug coverage) or a Medicare Advantage plan at the same time, though you do not have to.

To sign up by phone, call 1-800-MEDICARE (1-800-633-4227). Representatives are available Monday through Friday, 8 a.m. to 8 p.m. Eastern time. They can answer questions about your options and help you enroll over the phone. You can also call the Social Security Administration at 1-800-772-1213 if you prefer.

To sign up in person, visit your local Social Security office. You can find the nearest one at ssa.gov/locator. Bring your Social Security card, birth certificate, and proof of citizenship or legal residency. If you have current health coverage, bring proof of that as well.

When you can delay enrollment without penalty

If you are still working at 65 and covered by your employer's health plan, you may be able to delay Part B enrollment without owing a late penalty. This is called the Special Enrollment Period for people with group health plan coverage. You must meet two conditions: your employer must have 20 or more employees, and you must be covered under that employer's plan based on your current work.

If both conditions are true, you can wait to enroll in Part B until after you leave your job or lose the employer coverage, whichever comes first. You then have eight months from the month your coverage ends to enroll without penalty. This delay does not explore to Part A (hospital insurance) — you should still enroll in Part A when you turn 65, even if you delay Part B.

You will need to tell Medicare that you have employer coverage when you sign up for Part A. Bring a letter from your employer or your health plan stating that you are covered under a group health plan based on current employment. Without this documentation, Medicare may assume you missed your important date and assess a penalty.

What parts of Medicare you are signing up for

When you enroll, you are choosing coverage for different parts of Medicare. Part A covers hospital stays, skilled nursing facility care, hospice, and home health care. Most people do not pay a monthly premium for Part A if they or their spouse paid Medicare taxes while working. You should enroll in Part A when you turn 65.

Part B covers doctor visits, outpatient care, medical equipment, and preventive services. Part B has a monthly premium that changes each year. You can choose to enroll or delay, depending on your situation. If you have employer coverage, you may delay Part B without penalty. If you do not have other coverage, you should enroll in Part B during your Initial Enrollment Period to avoid a penalty.

Part D is prescription drug coverage. You can enroll in a Part D plan when you turn 65, or you can delay if you have other drug coverage. If you delay and later sign up, you may owe a penalty unless you had creditable coverage. You can also choose a Medicare Advantage plan (Part C) instead of Original Medicare, which combines Parts A, B, and usually D in one plan.

Documents and information you will need to sign up

Have these items ready before you start the enrollment process, whether you are signing up online, by phone, or in person.

  • Your Social Security number
  • Your date of birth
  • Your citizenship or legal residency status (you will need to state it, not necessarily provide a document online)
  • Information about any current health coverage, including the name of your employer or health plan and your policy number
  • If you are signing up in person: your Social Security card, birth certificate, and proof of citizenship or legal residency
  • If you have employer coverage and want to delay Part B: a letter from your employer or health plan confirming you are covered based on current work

If you are signing up online at Medicare.gov, you can save your progress and come back later. You do not have to complete it all at once. If you are calling or visiting in person, the process usually takes 15 to 30 minutes.

Frequently Asked Questions

What if I turn 65 while I am still working?

You can still enroll in Medicare. If your employer has 20 or more employees and you are covered under their health plan, you can delay Part B enrollment without penalty. You should still enroll in Part A. Once you leave your job or lose the employer coverage, you have eight months to enroll in Part B.

Can I change my mind after I sign up?

Yes, but only during certain times. You have a seven-month Initial Enrollment Period. After that, you can make changes during the Annual Enrollment Period (October 15 to December 7 each year) or if you have a may have access to life event like losing employer coverage or moving to a new state.

What if I was not a U.S. citizen for my whole working life?

You can still enroll in Medicare at 65 if you are a U.S. citizen or legal permanent resident and have lived in the United States for at least five years. You will need to provide proof of your status when you sign up. Call 1-800-MEDICARE if you have questions about your specific situation.

Do I have to enroll in Part D when I turn 65?

No, Part D is optional. If you do not take prescription medications or have other drug coverage, you do not need to enroll. However, if you delay Part D and later sign up, you may owe a penalty. If you have no other drug coverage, it is usually better to enroll when you turn 65.

What if I miss my important date by a few days?

Your enrollment window closes on a specific date. If you miss it by even one day and you do not have creditable coverage, you will owe a late penalty. The penalty is permanent. If you realize you missed the important date, contact Medicare right away — in rare cases, they may grant an extension if you have a good reason, but this is not may provide.