You must sign up for Medicare when you turn 65, or you may face a permanent penalty on your premiums

Yes, you need to sign up for Medicare. The federal government requires it when you turn 65, with very few exceptions. If you delay signing up without a valid reason, you will pay a higher premium for Part B (doctor and outpatient care) and Part D (prescription drugs) for as long as you have Medicare — even if you sign up years later.

The penalty is not a one-time fee. It is a percentage added to your monthly bill every month. For Part B, the penalty is 10 percent for each full year you could have had it but did not. For Part D, the penalty is 1 percent of the national average premium for each month you were without coverage. These penalties are permanent, so signing up late costs you money for life.

There are a few situations where you can delay without penalty. If you are still working and covered by your employer's health plan, or if you are covered by your spouse's employer plan, you may be able to wait. If you are a federal employee or railroad retiree, different rules may explore. But if you are not in one of these narrow categories and you turn 65, you should sign up during your enrollment window.

Key Takeaways

  • You must sign up for Medicare within three months before or after your 65th birthday, or you will face a permanent penalty on your premiums.
  • Part B and Part D penalties are calculated as a percentage of your monthly premium and stay with you for life, even if you sign up later.
  • If you are still working and covered by your employer's health plan, you may be able to delay without penalty, but you must tell Social Security this when you turn 65.
  • Your initial enrollment period is seven months long — three months before your birthday month, your birthday month itself, and three months after.
  • If you miss your initial enrollment period, you can sign up during the General Enrollment Period from January 1 to March 31 each year, but penalties will explore.

Your enrollment window: the seven-month initial enrollment period

Your Initial Enrollment Period starts three months before the month you turn 65 and ends three months after. That gives you seven months total. For example, if you turn 65 in June, you can sign up starting in March and must sign up by September to avoid a penalty.

You do not have to wait until your birthday month to sign up. Many people sign up as soon as the window opens, three months early. This gives you time to choose your plan, ask questions, and make sure everything is set before your coverage starts. If you sign up in March for a June birthday, your Part A (hospital insurance) and Part B coverage will begin on June 1.

If you miss this seven-month window, you will have another chance during the General Enrollment Period, which runs January 1 to March 31 every year. But any coverage you gain during this period does not start until July 1, and you will owe the permanent penalty for the months you were without coverage.

When you can delay without a penalty

You can postpone signing up for Part B without penalty if you are covered by a current employer's health plan — either your own job or your spouse's job. This is called creditable coverage. You must still sign up for Part A (hospital insurance) at 65, but Part B can wait as long as you are working and insured.

The catch is that you must tell Social Security you are still covered by an employer plan when you turn 65. If you do not report this, Social Security will assume you need to sign up for Part B, and you will face a penalty even though you had a valid reason to delay. Contact your local Social Security office or call 1-800-772-1213 to report your employer coverage.

When you leave your job or lose your employer coverage, you have eight months to sign up for Part B without penalty. This is called your Special Enrollment Period. The eight-month clock starts the month after your coverage ends. If you miss this window, the permanent penalty applies.

Federal employees, railroad retirees, and some other groups have different rules. If you worked for the federal government or the railroad, contact your agency's benefits office to learn your specific enrollment important date.

What the permanent penalty actually costs you

The Part B penalty is 10 percent of the standard monthly premium for each full year you could have had Part B but did not. The standard Part B premium changes every year. In 2024, the standard premium is $164.90 per month, so a one-year delay costs an extra $16.49 per month forever. A five-year delay costs an extra $82.45 per month for life.

The Part D penalty works differently. It is 1 percent of the national average drug plan premium for each month you were without coverage. Like Part B, this penalty is permanent. If you go three years without Part D coverage, you will pay a penalty every month you have Medicare, even if you eventually sign up.

These penalties do not go away if you switch plans or change your coverage later. They follow you. The only way to avoid them is to sign up during your initial enrollment period or during a Special Enrollment Period when you have a may have access to life event.

How to sign up during your enrollment period

You can sign up for Medicare 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. Online is usually the fastest. You will need your Social Security number and information about any current health coverage you have.

When you sign up, you will choose between Original Medicare (Part A and Part B) or a Medicare Advantage plan (Part C). You will also choose a prescription drug plan (Part D) unless you pick a Medicare Advantage plan that includes drug coverage. You do not have to make all these choices on the same day, but you should make them before your enrollment period ends.

If you are not sure which plan is right for you, Medicare offers free counseling through the State Health Insurance information Program (SHIP). You can find your state's SHIP office at shiptalk.org or by calling 1-877-839-2675. A counselor can walk you through your options without pushing you toward any particular plan.

What happens if you miss your enrollment period

If you do not sign up during your initial enrollment period and you do not have a may have access to reason to delay, you will have to wait until the next General Enrollment Period (January 1 to March 31) to sign up. Your coverage will not start until July 1 of that year, leaving you uninsured for months.

During those months without coverage, you are responsible for all your medical bills. Medicare will not cover anything. If you need hospital care or see a doctor, you pay the full cost out of pocket. This is why signing up on time matters — it is not just about avoiding a penalty, it is about making sure you have coverage when you need it.

Once you do sign up, the permanent penalty will be added to your Part B and Part D premiums. This penalty stays with you for the rest of your life. There is no way to remove it, even if you later realize you should have signed up sooner.

Special situations: still working, losing coverage, or changing jobs

If you are still working at 65 and covered by your employer's health plan, you can delay Part B. But you must report this to Social Security. Do not assume they will know. Call 1-800-772-1213 or visit your local Social Security office and tell them you are still working and insured. Ask them to note this in your file.

If you are covered by your spouse's employer plan, the same rule applies. You can delay Part B, but Social Security must know about it. When you eventually leave that job or lose that coverage, you have eight months to sign up for Part B without penalty.

If you are retired but covered by COBRA (continuation coverage from a former employer), COBRA counts as creditable coverage. You can delay Part B while you are on COBRA, but sign up before COBRA ends. Once COBRA ends, you have eight months to sign up for Part B.

If you are on active duty in the military, you can delay Part A and Part B. Certain family members of active duty service members may also be able to delay. Contact your military benefits office for details.

Frequently Asked Questions

What if I turn 65 while I am still working?

You must still sign up for Part A (hospital insurance) at 65, even if you are working. You can delay Part B if you are covered by your employer's health plan, but you must tell Social Security about your employer coverage. When you leave your job, you have eight months to sign up for Part B without penalty.

Can I sign up for Medicare before I turn 65?

Your enrollment period starts three months before your 65th birthday month. So if you turn 65 in June, you can sign up starting in March. You cannot sign up earlier than that unless you are on disability or have end-stage renal disease, which have different rules.

What if I already have health insurance from my job?

You still need to sign up for Part A at 65. For Part B, you can delay as long as your employer coverage continues, but you must report this to Social Security. When your employer coverage ends, you have eight months to sign up for Part B without penalty.

Do I have to sign up for Part D if I do not take many medications?

You do not have to sign up for Part D when you turn 65 if you do not need it. But if you go without Part D coverage for more than 63 days and then sign up later, you will pay a permanent penalty. If you think you might need prescriptions in the future, it is safer to sign up during your initial enrollment period.

What if I did not sign up and now I am past my enrollment period?

You can sign up during the General Enrollment Period from January 1 to March 31 each year. Your coverage will start July 1. You will owe a permanent penalty on Part B and Part D for the months you were without coverage. Contact Medicare at 1-800-MEDICARE to sign up as soon as possible.