• The Medicare annual enrollment period is from October 15 through December 7 each year.
  • During this time, you may make changes to your Medicare health or drug plans.
  • The changes that you can make include switching, adding, or dropping plans.
  • Any changes made during the annual enrollment period go into effect January 1 the following year.
  • There are also other types of Medicare enrollment periods that take place throughout the year.

Each year, private insurance companies that offer Medicare Advantage (Part C) or prescription drug (Part D) plans can make changes to the plans that they offer. These changes can affect things like coverage and cost.

After reviewing these changes for the coming year, you may decide that you’d like to switch or drop your plan. The Medicare annual enrollment period (AEP) allows you to do this.

AEP happens once each year. During this time, you can make changes to your Medicare health and drug plans.

Keep reading to learn more about this period, when it happens, and what specific changes you can make.

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You’re only able to enroll in Medicare at certain times throughout the year. These times are called enrollment periods.

AEP is one of Medicare’s enrollment periods. During AEP, you can make changes to your health and drug plans.

Why would I want to make changes?

Companies that provide Medicare Advantage (Part C) and Medicare Part D plans can decide to make changes for the upcoming year. These changes can affect things like:

  • the cost of your plan
  • what’s covered under your plan
  • which healthcare providers and pharmacies are considered to be “in network” for your plan

Because of this, your current health or drug plan may no longer be a good fit your health or cost needs for the coming year. During AEP, you can select a different health or drug plan for the next year that works better for you.

If your plan’s provider is making changes to your plan, they’ll send you an annual notice of change (ANOC) form. This explains the changes that will be included in your plan for the upcoming year.

What changes can I make during AEP?

During AEP, you can:

  • change from original Medicare (Part A and Part B) to a Medicare Advantage plan
  • change from a Medicare Advantage plan back to original Medicare
  • switch to a different Medicare Advantage plan
  • switch from a Medicare Advantage plan that includes prescription drug coverage to one that does not
  • switch from a Medicare Advantage plan that doesn’t include prescription drug coverage to one that does
  • join, switch, or drop a Part D prescription drug plan

AEP vs. OEP: What’s the difference?

You may have heard the terms “annual enrollment period” and “open enrollment period” used interchangeably. So, is there a difference between the two?

While the media, public, and insurance companies often use the term AEP, both Medicare and the Centers for Medicare & Medicaid Services (CMS) refer to this time frame as Medicare’s “open enrollment period.”

Most of the time, AEP and Medicare open enrollment are referring to the same time frame.

The difference in terminology is likely to avoid confusion between AEP and the separate open enrollment periods for Medicare Advantage and Medigap, which occur at other times during the year.

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AEP happens every year from October 15 to December 7.

During this time, you can make changes to your plans in order to best meet your needs for the upcoming year. These changes will go into effect starting on January 1.

If the provider of your current plan has made changes that affect things like cost and coverage, they’ll send you an ANOC. You’ll typically receive this by mail sometime in September.

Information about the different Medicare health and drug plans for the upcoming year will become available beginning in October. This gives you time to review and compare different plans before AEP begins on October 15.

In addition to AEP, there are several other Medicare enrollment periods when you can make certain changes to your plan(s).

General enrollment period

Medicare’s general enrollment period lasts from January 1 to March 31. During general enrollment, you can:

  • enroll in original Medicare if you didn’t do so when you were first eligible
  • join a Medicare Advantage plan if you have Part A coverage and get Part B coverage for the first time during this enrollment period

Your coverage will start on July 1 if you make changes during this period. Additionally, you may have to pay a late enrollment penalty on your premiums if you’re enrolling late.

Part D enrollment (special circumstances)

From April 1 through June 30, you can enroll in a Part D plan if both of the following are true:

  • you have to pay a premium for Part A
  • you first enrolled in Part B during the general enrollment period

If you enroll in a Part D plan during this time frame, your prescription drug coverage will begin on July 1. It’s possible that you’ll have to pay a late enrollment penalty on your Part D premium for enrolling late.

Medicare Advantage open enrollment period

This occurs from January 1 to March 31. During this time frame, you can:

  • change from a Medicare Advantage plan back to original Medicare
  • if you choose to go back to original Medicare, you can also join a Part D plan at this time
  • switch to a different Medicare Advantage plan (with or without prescription drug coverage)

You may only make one change during this enrollment period. Your changes will go into effect beginning the first month after your change request is received by the provider.

Medigap open enrollment period

Medigap is also called Medicare supplement insurance. It helps cover some of the expenses under original Medicare.

The Medigap open enrollment period lasts for 6 months. It begins when both of the following are true:

  • you’re age 65 or older
  • you’ve enrolled in Part B for the first time

Medigap can only be used with original Medicare. If you have a Medicare Advantage plan, you cannot enroll in Medigap.

Special enrollment periods

Sometimes you can make changes to your Medicare plans outside of the enrollment periods discussed above. This is referred to as a special enrollment period.

You’re eligible for a special enrollment period if you didn’t sign up for Medicare when you were first eligible because you were covered under an employer-provided plan. This includes coverage under a spouse or family member’s plan.

You can enroll in Medicare anytime you’re still covered by this plan or in the 8-month period after employer-provided coverage ends. If you enroll during a special enrollment period, you typically don’t pay late enrollment penalties.

There are also special enrollment periods associated with Medicare Advantage and Part D plans. These periods are triggered by changes to your current plan or life events like moving, marriage, or divorce.

These are just a few examples of when you can change your Medicare health or drug plan in a special enrollment period. Also, the length of a special enrollment period and the type of changes you can make may vary based on your situation.

For additional help understanding Medicare’s enrollment periods, the following resources are available:

Seeking assistance can pay off

A 2018 study evaluated a Medicare plan selection assistance program over the course of 4 years. As part of the program, pharmacy students assisted Medicare beneficiaries with Part D plan selection.

The study found that, depending on the year, Medicare beneficiaries had an average projected savings of between $278.71 and $1,382.90 after receiving assistance in choosing and enrolling in a new Part D plan.

Medicare’s AEP occurs in the fall of each year, from October 15 to December 7. During AEP, you can make changes to your Medicare health and drug plans. These changes will be effective beginning on the first day of the new year.

You may choose to make changes to your plan because it no longer suits your needs or will cost more in the upcoming year. If your plan is making changes that impact its cost or coverage, you’ll be notified before AEP begins.

It’s always important to review your plan each year, comparing it to others that are available in your area. If you have additional questions or concerns, you can contact Medicare, a specific plan’s provider, or your local SHIP office for help.