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When to Enroll in Medicare: Eligibility, Deadlines, and More

Retired couple learning about Medicare enrollment options

There are four different periods during which you can enroll in or change your Medicare plan:

  • Initial Enrollment Period is a seven-month window around your 65th birthday
  • Special Enrollment Period allows you to make changes to your Medicare plan due to special circumstances
  • General Enrollment Period allows you to sign up in case you missed your Initial Enrollment Period
  • Annual Enrollment Period is a yearly opportunity to make changes to your Medicare Advantage coverage from October 15 to December 7

Do I automatically receive Medicare when I turn 65?

Most people qualify for Original Medicare (Parts A and B) when they turn 65. But you’re not automatically enrolled on your 65th birthday. You may still need to apply for Original Medicare.

How do I sign up for Medicare for the first time?

There is a seven-month window around your 65th birthday called the Initial Enrollment Period (IEP), when you can apply for Medicare:

  • Three months before the month you turn 65
  • The month you turn 65
  • Three months after the month you turn 65

If you’re receiving Social Security benefits at least four months before your 65th birthday, you’re automatically enrolled in Parts A and B. Social Security will send you Medicare information and a Medicare card prior to your 65th birthday.

If you’re receiving group health insurance through your employer or your spouse’s employer, you may be able to delay Part A and Part B without a late enrollment penalty.

During your IEP, you also have an option to pick a Medicare Advantage (Part C) or Prescription Drug Plan (Part D) from a private insurer, once you’ve applied to Original Medicare.

Medicare Special Enrollment Period

The SEP is an additional window of time to apply, add, drop, or change your Medicare coverage outside of enrollment periods, due to certain life circumstances. If you didn’t apply to Original Medicare during your IEP because you had not yet retired and still had health insurance through your employer or your spouse’s employer, the SEP allows you to sign up for Original Medicare without a penalty.

The SEP also allows you to make Medicare plan changes for a number of reasons. For example, you can adjust insurance if you move out of your plan’s coverage area or if you start qualifying for Extra Help.

Medicare General Enrollment Period

The General Enrollment Period for Original Medicare is January 1 through March 31 each year. Apply during this time if you missed the IEP (when you were first eligible), but keep in mind you may have to pay a late enrollment penalty.

Medicare Annual Enrollment Period

You can also receive Original Medicare benefits through a Medicare Advantage plan, also known as Medicare Part C. To enroll in a Medicare Advantage plan, you must go through a private insurer and already have Original Medicare (Parts A and B). Medicare Advantage plans add benefits Original Medicare doesn’t offer, such as dental, vision, and hearing insurance.

During the Annual Enrollment Period (also called the Annual Election Period) from October 15 to December 7 of each year, you can add, drop, or change your Medicare Advantage plan and prescription drug plans if you choose. You also have another opportunity to change your Medicare Advantage plan from January 1 to March 31 during the Medicare Advantage Open Enrollment Period.

Medicare enrollment deadlines and penalties

The government does require you to have insurance, so if you don’t have coverage, try to sign up within that seven-month Initial Enrollment Period (IEP) to avoid a coverage gap fee.

If you miss that sign-up window and you weren’t automatically enrolled, you can apply during the Medicare Annual Enrollment Period, which is October 15 to December 7 each year.

However, if you missed the IEP because of life circumstances, you might be eligible to apply during a Special Enrollment Period (SEP).

Explore all your Medicare plan options to find the right plan for you.


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