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6 Key Medicare Enrollment
Dates You Should Know

Whether you’re approaching 65, getting ready to retire, or want to switch Medicare plans, there are six specific dates and timeframes you’ll need to know. To view a specific enrollment period, click on the appropriate link:

Initial Enrollment Period

We’ve explained the Medicare enrollment dates below to make it easier for you to figure out what you need to do and when to do it.

1. Initial Enrollment Period (IEP)

This enrollment period revolves around your 65th birthday, which is the first time you’reeligible to enroll in Medicare. IEP starts three months BEFORE you turn 65, includes your birthday month, and ends three months AFTER you turn 65.

Initial enrollment period timeline that demonstrates Months 1 to 3, Month 4 turning 65, and Months 5 to 7 as when to enroll in Medicare

During this seventh-month period, you can enroll in Original Medicare (Parts A and B), a Medicare Advantage plan (Part C) or a stand-alone Prescription Drug plan (Part D).

You’ll probably receive a lot of information from different Medicare providers during IEP, including us. Ourfree guidebook is a great resource to help you understand your Medicare options.

2. Medigap Open Enrollment Period

Once you’ve signed up for Original Medicare, you can enroll in a Medigap (Medicare Supplement) plan to help with the costs not covered by Original Medicare. The best time to enroll in this plan type is during the Medigap Open Enrollment Period, which begins as soon as your Part B coverage starts and lasts six months.

What Happens If I Miss This Enrollment Period?

You may still be able to purchase a Medigap plan after the enrollment date; however, the costs may be higher, and your policy options might be limited. At Blue Cross Blue Shield of Massachusetts, we allow you to purchase a Medigap plan at any time of the year.

3. General Enrollment Period (GEP)

If you missed IEP, don’t worry. You can also sign up for Original Medicare during the General Enrollment Period (GEP), which lasts fromJanuary 1 through March 31 each year.

General enrollment period timeline that demonstrates January 1st to March 31st is the typical time to enroll in Medicare

4. Annual Enrollment Period (AEP)

This enrollment period happens every year fromOctober 15 to December 7. It’s a chance to ensure yourMedicare plan still meets your needs and review other coverage options.

During AEP, you can:

Switch from Original Medicare to a Medicare Advantage plan
Change Medicare Advantage plans
Add or drop a Prescription Drug plan (Part D)

Annual enrollment period timeline that demonstrates October 15th to December 7th as the annual enrollment period for Medicare

5. Medicare Advantage Open Enrollment Period (MA OEP)

While the Annual Enrollment Period is for anyone that is Medicare-eligible, this enrollment period isonly for people already enrolled in a Medicare Advantage plan. It takes place fromJanuary 1 through March 31 each year and is an opportunity to switch to a different Medicare Advantage plan or disenroll from a Medicare Advantage plan and move to Original Medicare. You can only make one policy change during this period.

Medicare Advantage open enrollment period timeline that demonstrates January 1st to March 31st as the Medicare Advantage open enrollment period

6. Special Enrollment Period (SEP)

Life is unpredictable, and sometimes events occur that impact your Medicare coverage. You may qualify for a special enrollment period (SEP) under certain circumstances. The SEP allows you to change to your Medicare Advantage or Prescription Drug plan outside the other enrollment dates. The circumstances for SEPs can be categorized into two categories:

Special Enrollment Period for Qualifying Life Events
Special Enrollment Period for Working Past 65

Special Enrollment Period for Qualifying Life Events

If you have Medicare and experience a qualifying life event, you may qualify for a2-month period when you can switch to a different Medicare Advantage or Prescription Drug plan. Some of these qualifying life events include:

You move out of your current plan’s network area
Your plan stops serving your area, reduces its network, or consistently receives low Star-Ratings.
You move into a nursing home or long-term care facility

There are many other qualifying events. You canfind a complete list here.

Special Enrollment Period for Working Past 65

If you’ve worked past 65 and qualified to delay Medicare enrollment, there is a 2-month period— beginning when your employer coverage ends — when you can enroll in a Medicare Advantage or Prescription Drug plan without penalty. If you are only enrolling in Original Medicare (Parts A and B), you have eight months.

Special enrollment period timeline that demonstrates qualifying life event 8-month period and working past 65 two-month time period

Regardless of your situation, your coverage starts the month after you sign up during your SEP.

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Review Your Medicare Coverage Options

Your health needs change constantly. We recommend reviewing your coverage options from time to time. If you need to change your plan, now you know which Medicare enrollment dates you can switch or add coverage.