Medical Expense✓ Verified · outline & fact-checked · Sep 2026Difficulty 1/5
The Medicare Part D Annual Enrollment Period (AEP) runs each year:
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Answer & full 3-part explanation (select an option above, or peek)
Why D is correct
The Medicare Part D Annual Enrollment Period (AEP), also known as the open enrollment period, runs from October 15 through December 7 each year. During this window, beneficiaries may join, switch, or drop a Part D prescription drug plan, with coverage effective January 1 of the following year. The AEP also serves as the annual open enrollment period for Medicare Advantage plans. This fall window is distinct from the Medicare Advantage disenrollment period in early January.
Why the other options are wrong
- A) January 1 through March 31 is the Part B General Enrollment Period and also the Medicare Advantage Open Enrollment Period in recent years, not the Part D AEP.
- B) April 1 through June 30 is not a Medicare Part D enrollment window.
- C) July 1 through September 30 is not a Medicare Part D enrollment window.
Memory hook
Fall for changes: Oct 15 - Dec 7. Pick a Part D plan then and coverage clicks on January 1.