What is AEP? Medicare’s Annual Enrollment Period
AEP stands for Annual Enrollment Period. It is the time of year when Medicare Beneficiaries can switch or enroll in Medicare Part D, drug plans and / or Medicare Advantage Plans.
Do you love a good acronym? How about a very large amount of them?
The health and insurance industries are nothing if not full of confusing acronyms. Moreover, “industry people” will just assume you know them all. AEP is no exception, so let’s discuss what actually is the Medicare Annual Enrollment Period.

The Definition of AEP
AEP stands for Medicare’s Annual Enrollment Period. It is defines the period of time each year eligible seniors can enroll in both:
In addition, you will not be required to go through medical underwriting to join these plans. (ESRD is an exception.)
What is SEP? and What is IEP?
Outside of a SEP (Special Enrollment Period) or your IEP (Initial Enrollment Period), this is the only time that you can join a Part D or Part C plan. Yes, I know, more acronyms!
SEP is Special Enrollment Period,
More Medicare Acronym fun!
IEP is Initial Enrollment Period, and
OEP is Open Enrollment Period.
In addition, AEP is one of the two times you can switch plans, if you are already in one.
The US government just added the Medicare Advantage Open Enrollment Period. This is a second period of time – Jan. 1 – March 31 – where you can switch plans once if you are already in a plan.
When is AEP?
The Medicare Annual Enrollment Period is October 15th – December 7th. The changes you make during this period of time will take place for the following year on January 1st.
Possible Changes During the Medicare Annual Enrollment Period (AEP)
- If you have Original Medicare, or Original Medicare and a Supplement, you can join a Medicare Advantage Plan or join/change a Prescription Drug Plan.
- Next, you can leave a Medicare Advantage (MA) Plan for another MA plan or to revert to Original Medicare.
- You can switch from one stand alone drug plan to another stand alone drug plan.
- Finally, you can drop your drug plan. (If you do this, you can still keep your Original Medicare and/or supplement.
Does AEP apply to Medigap (Medicare Supplement) Plans?
No, AEP does not apply to Medigap (supplements). You can switch a supplement plan at any time. However, you will be subject to medical underwriting. This means that you are not guaranteed to be accepted into the Medigap plan.
- Related Reading: Which is better, Medicare Advantage or Medigap?
How do I Switch Plans / Join a Plan During Medicare Annual Enrollment Period

You can start researching and learning about the plans available to you the next year, starting October 1st. However, you will not be able to complete an enrollment application until October 15th.
When switching/joining a MA/MAPD or Drug Plan, I highly suggest using an independent insurance agent.
There are many considerations when choosing a plan, and she/he will help you in making sure you pick the right plan for you.
If you live in Nebraska, please give me a email/call/text, and I will be happy to help.)
That said, you can also research plans and see their ratings at https://www.medicare.gov/find-a-plan.

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