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When to apply for Medicare

Page last updated on: 7/15/26

When do you apply for Medicare?

When you turn 65, you're typically eligible to apply for Medicare Part A (hospitalization) at no cost, provided you have paid into the Medicare program through your taxes for at least 10 years. You're also eligible for Part B (medical) if you're a citizen or permanent resident of the United States. Additionally, if you have a disability, you may qualify even if you aren't yet 65.

Apply for Medicare by your 65th birthday

The three months before your birthday, your birthday month and the three months after your 65th birthday are your Initial Enrollment Period (IEP).

During your Initial Enrollment Period, you can apply for:

  • Original Medicare (Parts A and B)
  • Medicare Advantage plan (Part C) and/or
  • Prescription drug plan (Part D)

Tip: It may be best to apply during the three months before your birthday to help prevent delays in Part B coverage.

How to enroll if you are not automatically enrolled

Call

Call the Social Security Administration.

800.772.1213. (TTY 800.325.0778)

In person

Visit your local Social Security office.

Office locator

 

Online

Apply online.

ssa.gov

If you're already receiving benefits from Social Security or the Railroad Retirement Board (RRB), you'll automatically be enrolled in Original Medicare (Parts A and B) on the first day of the month you turn 65. You don't need to do anything. Watch for your red-white-and-blue Medicare card to come in the mail.

What happens if you miss your Medicare enrollment period?

If you don’t apply for Medicare Part B and Part D during your Initial Enrollment Period, you could end up paying a late enrollment penalty, delaying coverage and paying higher premiums.

Switching Medicare plans

If you have a Medicare Advantage or Part D prescription drug plan, the Annual Enrollment Period (AEP) gives you the chance to switch to a different plan or health insurance provider. Your new plan benefits take effect on Jan. 1 of the upcoming year.

  • Annual Enrollment Period: Oct. 15 – Dec. 7
  • What you can do: Switch to a different Medicare Advantage or Part D prescription drug plan
  • New plan starts: Jan. 1 of the upcoming year

Dropping or changing your Medicare Advantage plan

During the Medicare Advantage Open Enrollment Period (OEP), you can change your coverage between Jan. 1 and Mar. 31. During these three months, you can change to a different Medicare Advantage or MAPD plan or disenroll from your plan and return to Original Medicare, provided you were previously enrolled in an Advantage or MAPD plan.

When you make a change during OEP, your new plan starts on the first day of the next month. You are only allowed one plan change.

  • Open Enrollment Period: Jan. 1 – Mar. 31
  • What you can do: Change to a different Medicare Advantage or MAPD plan, or disenroll and return to Original Medicare
  • Who it applies to: People already enrolled in Medicare Advantage or MAPD
  • When the new plan starts: First day of the next month
  • Limit: One plan change

Use your special enrollment period

In some situations, you'll have a special enrollment period (SEP). The SEP allows you to change your Medicare Advantage (Part C) and prescription drug (Part D) plans or go back to Original Medicare (Parts A and B) outside of the normal time constraints.

You may qualify if:

  • You move outside the area your current plan covers
  • You become eligible for a low-income subsidy
  • You lose creditable prescription drug coverage from your employer
  • Your plan is no longer available

Applying for a Medigap plan

You have a six-month Medigap open enrollment period that begins on the first day of the month in which you are both 65 or older and enrolled in Part B. This is the best time to apply because it's your "guaranteed issue" period, and you'll be accepted into a Medigap plan even if you have health problems.

Frequently asked questions

Your Initial Enrollment Period (IEP) is the three months before your 65th birthday month, your birthday month and the three months after your birthday month. During this time, you can apply for Original Medicare, a Medicare Advantage plan and/or a Part D prescription drug plan.

If you're already receiving benefits from Social Security or the Railroad Retirement Board (RRB), you'll automatically be enrolled in Original Medicare (Parts A and B) on the first day of the month you turn 65. If you're not already receiving these benefits, you'll need to enroll yourself.

You can enroll in Medicare Parts A and B by calling the Social Security Administration, visiting your local Social Security office or signing up online at ssa.gov.

If you don't apply for Medicare Part B and Part D during your Initial Enrollment Period, you could face a late enrollment penalty, delayed coverage and higher premiums. However, you may be able to delay enrollment if you have creditable coverage through an employer or union.

Creditable coverage is coverage that's as good as Original Medicare. Many people receive creditable coverage through an employer or union.

Not necessarily. If you have creditable coverage through an employer or union, you may be able to delay enrolling in Medicare Part B without paying a late enrollment penalty. Creditable coverage is coverage that's as good as Original Medicare. When your employer coverage ends, you may qualify for a Special Enrollment Period to enroll in Medicare.

Yes. In some situations, you may have a guaranteed issue right to purchase a Medigap plan outside your annual enrollment period. For example, if you have a Medicare Advantage plan and move out of your plan's service area.

Guaranteed issue is a period when you have the right to buy a Medigap plan and cannot be denied coverage because of health problems. For most people, this occurs during the six-month Medigap open enrollment period that begins when they are both age 65 or older and enrolled in Medicare Part B. After that period, you may be subject to underwriting, and coverage could cost more or be denied.

After your guaranteed issue period ends, you may be subject to underwriting. The health plan can consider your health, age and other factors before accepting your application. Coverage may be denied or cost more.

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