Learn about Medicare enrollment periods

Medicare has many enrollment periods and rules about when you can enroll in a Part D plan or make changes to your coverage. Knowing this information is important so you can avoid enrollment penalties and lapses in coverage.

Use the chart below to see a summary of Medicare enrollment dates and determine when you can enroll in a plan.

Enrollment period What you can do When you can do it
Initial enrollment period (IEP) Enroll in a prescription drug plan, Medicare Advantage (MA) plan or MA plan with prescription drug coverage Three months prior to, the month of, or three months after you turn 65. Or, after month 24 of receiving disability benefits.
Annual enrollment period (AEP) Existing Medicare beneficiaries can enroll in or change to a prescription drug plan, Medicare Advantage (MA) plan or MA plan with prescription drug coverage October 15 to December 7, annually (coverage effective January 1 of the following year)
Medicare Advantage open enrollment period (MA OEP) Disenroll from a Medicare Advantage (MA) plan and enroll in another MA plan (with or without prescription drug coverage) or Original Medicare and, if needed, a stand-alone prescription drug plan January 1 to March 31, annually (change effective the first of the month after you submit the request)
Special enrollment period (SEP)* Enroll in a prescription drug plan or Medicare Advantage plan If you qualify for an SEP, you can enroll after an IEP or AEP has ended.

*Learn about the special circumstances that may make you eligible for an SEP at Medicare.gov.

Do you have questions about enrollment periods? Learn more at Medicare.gov. Or, contact our Medicare Solutions specialists for help determining which enrollment period you can use.

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