Difference Between the Medicare Open Enrollment Period and Annual Enrollment Period

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The Medicare Annual Enrollment Period, or “AEP,” begins October 15th and ends December 7th.  During the AEP, people can make changes to either their Medicare Advantage Part C plan or their Stand-alone Medicare Part D prescription drug plan.  Plan changes made during the AEP are effective January 1st.

The Medicare Open Enrollment Period, or “OEP,” begins January 1st and ends March 31st.

The OEP is sort of a “get out of jail free card” for people enrolled in Medicare Advantage (Part “C”) who meant to update their plan during the Fall Annual Enrollment Period (AEP) but did not get around to it.

If you are enrolled in a Medicare Advantage plan, during the OEP you have one more chance to change your Medicare Advantage plan OR you can disenroll entirely from Medicare Advantage and return to Original Medicare and then enroll in a Stand-Alone Part D prescription drug plan.

Changes made in January are effective February 1st; changes made in February are effective March 1st; and changes made in March are effective April 1st.  After March 31st whichever plan that is in place will remain effective for the remainder of the calendar year, unless you qualify for a type of Special Election Period (“SEP”.) 1

If you have a Stand-alone Part D prescription plan, you are not able to update this using the OEP election.

And unlike the AEP, the OEP is not supposed to be an advertised election period.

If you have questions about prior authorizations, physician referrals, or any other Medicare questions, please contact your Member Agent.

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Member Agents are here to help you and their educational services are always free of charge.

1Special Election Periods (“SEPs”) are triggered throughout the year for a variety of reasons.  Some examples of SEPs are losing job-based health insurance, moving outside of a plan service area, and low-income subsidy just to name a few.

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