The Medicare Open Enrollment Period (OEP) is a limited window each year designed specifically for individuals who are already enrolled in a Medicare Advantage (Part C) plan. This period runs from January 1 through March 31 each year, and it allows beneficiaries to make a one-time change if they find that their current Medicare Advantage plan is not meeting their needs. 

During the Open Enrollment Period, you may switch from one Medicare Advantage plan to another, or you may disenroll from your Medicare Advantage plan and return to Original Medicare (Part A & Part B). If you choose to return to Original Medicare, you are also allowed to enroll in a standalone Medicare Part D prescription drug plan to help cover medication costs.

Changes made during OEP take effect on the first day of the month following the date your request is submitted, which allows for quicker adjustments compared to other enrollment periods. This makes OEP especially helpful if you experience unexpected issues early in the year, such as difficulty accessing doctors in your plan’s network, higher-than-anticipated prescription costs, or increased out-of-pocket expenses.

It’s important to understand what cannot be done during OEP. You cannot switch from Original Medicare to a Medicare Advantage plan if you are not already enrolled in one. Additionally, OEP does not provide guaranteed rights to enroll in or change Medicare Supplement (Medigap) plans.

The Medicare Open Enrollment Period is not meant for routine plan shopping, but rather as a safeguard for beneficiaries who need to correct a coverage decision made during the Annual Enrollment Period. Because only one change is allowed, it’s important to review your options carefully before making a decision.

If you’re unsure whether the Open Enrollment Period applies to you—or if making a change is in your best interest—working with a licensed Medicare agent can help you understand your choices, avoid mistakes, and feel confident in your coverage for the rest of the year.