Medicare AEP vs. OEP: Understanding the Medicare Enrollment Periods

Understanding the Difference Between Medicare Open Enrollment and Annual Enrollment

Two key periods, two different purposes — here’s what agents need to know.

As a Medicare agent, knowing the distinction between the Annual Enrollment Period (AEP) and the Medicare Advantage Open Enrollment Period (MA OEP) is essential to properly guide your clients through their coverage options. While the names sound similar, these enrollment windows serve different purposes — and knowing when and how to act can make all the difference for your clients and your business.

Annual Enrollment Period (AEP)

Dates: October 15 – December 7

AEP is the big one. This is when most Medicare beneficiaries can make broad changes to their coverage. During this period, your clients can:

• Switch from Original Medicare to a Medicare Advantage (MA) plan

• Move from Medicare Advantage back to Original Medicare

• Change from one MA plan to another

• Enroll in, drop, or switch a standalone Part D prescription drug plan

Why it matters:
This is the busiest and most important time of year for agents — your opportunity to help clients compare plans, evaluate benefits, and ensure they have the right coverage heading into the new year.

Medicare Advantage Open Enrollment Period (MA OEP)

Dates: January 1 – March 31

MA OEP is designed specifically for clients who are already enrolled in a Medicare Advantage plan. It’s a narrower window that allows one-time adjustments for those who may have second thoughts after AEP or experience a change in needs early in the year.

During this period, clients can:

• Switch from one Medicare Advantage plan to another

• Drop their MA plan and return to Original Medicare

• Add a Part D plan if they move back to Original Medicare

Who can use it:
Only beneficiaries currently enrolled in a Medicare Advantage plan — not those on Original Medicare.

Quick Comparison:

How Agents Can Add Value

Use AEP to help clients make confident, informed choices about their overall coverage — then use MA OEP as a follow-up opportunity to check in with your Medicare Advantage clients, answer questions, and assist anyone who might not be satisfied with their new plan.

Both periods give you a chance to strengthen client relationships and position yourself as their trusted, year-round Medicare advisor.

Want to Be Ready for Every Enrollment Season?

Partner with PSM Brokerage to access leading Medicare Advantage carriers, enrollment tools, marketing resources, and expert support that help you succeed during both AEP and MA OEP.

👉 Learn More About Partnering with PSM Brokerage

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