Understanding AEP and OEP: Key Medicare Enrollment Windows
Each year, Medicare offers two major opportunities to review and adjust your coverage:
Annual Election Period (AEP): October 15 – December 7
Open Enrollment Period (OEP): January 1 – March 31
These enrollment periods are critical for ensuring that your Medicare plan continues to meet your healthcare and prescription needs. Knowing the differences between the two can help you make informed choices and avoid costly mistakes.
What Is the Annual Election Period (AEP)?
AEP (October 15 – December 7) allows anyone with Medicare to:
Switch from Original Medicare to a Medicare Advantage plan
Switch from one Medicare Advantage plan to another
Join, drop, or change a Part D prescription drug plan
Changes made during AEP go into effect on January 1 of the following year.
What Is the Open Enrollment Period (OEP)?
OEP (January 1 – March 31) is only for people already enrolled in a Medicare Advantage plan. During this time, you can:
Switch to another Medicare Advantage plan
Drop your Medicare Advantage plan and return to Original Medicare
Enroll in a stand-alone Part D plan if returning to Original Medicare
Apply for a Medigap plan (though medical underwriting may apply)
What You Cannot Do During OEP:
Switch from Original Medicare to a Medicare Advantage plan
Join or switch Part D plans if you’re on Original Medicare
Reasons People Change Plans
A preferred doctor is no longer in-network
A key prescription is no longer covered
Co-pays, premiums, or out-of-pocket costs have increased
You want more provider freedom or better plan extras
Things to Review Before Making a Switch
Your plan’s Evidence of Coverage (EOC)
The Annual Notice of Change (ANOC) from your plan provider
Updated drug formularies and provider directories
Out-of-pocket maximums and cost-sharing structure
Whether your medications and doctors are still covered
Pro Tip: A zero-premium plan may still come with higher deductibles or limited provider access. Be sure to review total costs—not just monthly premiums.
Switching Is Easy—But Choose Wisely
To change plans during AEP or OEP, just apply for the new plan. Once approved, you’ll be automatically disenrolled from your current plan when the new one begins. No extra paperwork is required.
If you’re dropping a Medicare Advantage plan and returning to Original Medicare, consider applying for a Medigap plan first to avoid coverage gaps—especially if you’re no longer in your Medigap Open Enrollment window.
We’re Here to Help You Make the Right Choice
Navigating these enrollment periods doesn’t have to be overwhelming. Our licensed agents can:
Compare plans side by side
Explain coverage details and fine print
Help you understand penalties, drug coverage, and Medigap eligibility
Enroll you in a new plan in just minutes
Call 1-877-413-1556 or schedule your free consultation today by clicking the button below.