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Medicare Enrollment

This page covers some helpful questions to ask when preparing to enroll in a Medicare plan. See the answers to each one below.

You can enroll in a Medicare plan during one of the following four enrollment periods:


  • Initial Enrollment Period (IEP), which begins when you’re first eligible for Medicare
  • Annual Enrollment Period (AEP), which occurs from October 15 through December 7
  • Open Enrollment Period (OEP), from January 1 through March 31
  • Special Enrollment Period (SEP), during specific personal circumstances


Read more about each of these enrollment periods in the questions below. You can also visit our Unpacking Medicare enrollment page for more information.

The Initial Enrollment Period (IEP), or IEP, is a 7-month period of time that you can enroll in Medicare. Your personal IEP centers around the “qualifying event” that makes you eligible for Medicare.


Your Initial Enrollment Period (IEP):


  • Starts 3 months before the month you become eligible
  • Includes the month you become eligible
  • Ends 3 months after the month you became eligible


Your qualifying event may be your 65th birthday1; or — if you are under 65 and have a qualifying disability — it may be your 25th month of receiving certain government disability benefits.2


1If your birthday falls on the first of any month, your 7-month IEP begins and ends one month sooner. For example, if your birthday is July 1, your 7-month IEP is the same as if you were born in June — beginning in March and ending in September.


2If you join during one of the 3 months before your 25th month of disability benefits from Social Security or the Railroad Retirement Board, your coverage will begin the first day of your 25th month of entitlement to disability payments.

Medicare’s Annual Enrollment Period begins October 15 and ends December 7 of each year. The choices you make generally take effect January 1 of the following year.


During AEP you may:


  • Switch Medicare plans
  • Join a new Medicare plan
  • Cancel your Medicare plan

Open Enrollment takes place from January 1 through March 31 annually. It allows individuals enrolled in a Medicare Advantage plan to make a one-time election to go to either another Medicare Advantage plan or Original Medicare.

  • The Special Enrollment Period allows you to join, switch or cancel a Medicare plan when you have special circumstances. Some examples include: You newly get, lose or have a change in your Medicaid or Extra Help status
  • You recently involuntarily lost your creditable coverage (as good as Medicare’s)
  • You are leaving/losing/starting a job, or joining/leaving a union
  • You belong to a Pharmacy Assistance Program provided by your state
  • You recently moved outside the service area for your current plan, or you recently moved and this plan is a new option for you
  • You live in, are moving into, or recently moved out of a nursing home or long-term care facility


The Special Enrollment Period (SEP) reasons listed above are examples and do not include every situation that may qualify for SEP enrollment.

You may join, switch or cancel your current Medicare plan during Medicare's Annual Enrollment Period (AEP), or if you meet certain circumstances during Open Enrollment Period (OEP). You may also make changes to your Medicare coverage during a Special Enrollment Period (SEP), when certain events happen in your life.


For more information on what you can do during different enrollment periods, see the previous questions on this page.

When you enter an enrollment period, there are a few steps you can take to enroll. You can choose one of the following Medicare enrollment options:


  1. Enroll on
  2. Enroll on
  3. Enroll using the plan’s paper enrollment form
  4. Enroll by calling Aetna at ${dynamicPhone} ${tty}, ${hours}

The Part D late enrollment penalty is an amount that’s permanently added to your monthly Part D premium if:

  • You don’t sign up when you’re first eligible for Medicare, and
  • You don’t have similar drug coverage (coverage as good as Medicare’s)

For more information, please refer to your Evidence of Coverage.

More questions? We’ve got answers

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Talk to a licensed agent at ${dynamicPhone} ${tty}, ${hours}

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