The Centers for Medicare & Medicaid Services (CMS) recommends that you assess your Medicare coverage options every year to determine if you should change from Original Medicare to a Medicare Advantage plan, or select a new plan. Before making any decisions, it’s important to understand the purpose of the Annual Enrollment Period and the Open Enrollment Period, what plan changes you can make and how to navigate your options.

The Medicare Advantage Open Enrollment Period (OEP) takes place annually from January 1 to March 31 and has a different purpose from the Medicare Annual Enrollment Period (AEP), which takes place from October 15 to December 7. 

Medicare Annual Enrollment Period (AEP) vs. Medicare Advantage Open Enrollment Period (OEP)

When you sign up for Medicare, you have the option of selecting Original Medicare, which is administered through the federal government, or a Medicare Advantage plan, which is offered through a private insurer. 

During AEP, you can enroll in a plan for the first time or make changes to your existing plan. This is also the time you can switch to Medicare Advantage if you have Original Medicare. 

AEP is different from OEP, which takes place at the beginning of the year and only applies to those who are already enrolled in a Medicare Advantage plan and want to switch to a different Medicare Advantage plan or return to Original Medicare. OEP is also the right time to change what you just selected during AEP if you feel like you made a mistake.

During the Medicare Advantage OEP, you can only change your coverage once because your new coverage begins the following month. That’s why it’s important to understand your plan options during AEP, as you can only make one change during OEP. 

The following chart summarizes the main differences between AEP and OEP:

	OEP	AEP
Enrollment Period	January 1 to March 31	October 15 to December 7
Allowed Coverage Changes	Switch from one Medicare Advantage plan to anotherTerminate your Medicare Advantage coverage and return to Original MedicareAdd Part D prescription drug coverage if your current Medicare Advantage plan does not have drug coverageSwitch from a Medicare Advantage plan that doesn’t offer drug coverage to one that doesChoose a different Medicare Medical Savings Account (MSA) plan or disenroll from the program	Change to a Medicare Advantage plan if you are already enrolled in Original Medicare Parts A and BEnroll in or change your standalone Part D prescription drug planChoose a different Medicare Advantage planSwitch to Original Medicare from a Medicare Advantage planOpt out of Medicare completely
Coverage Begins	The following month	January 1 of the following year

How to Navigate Medicare Advantage Options

Comparing Medicare Advantage plans can be overwhelming. When deciding which plan is best for you, start by examining which networks your doctors belong to. 

After finding a plan that has your doctors in-network, analyze your healthcare needs and which plan’s benefits best suit them. For example, if you don’t take many prescription drugs, you may be less inclined to pay more for drug coverage. If you regularly take medications, review each plan’s  prescription drug formulary prior to making a decision. The drug formulary tells you which drugs are covered by the plan. 

Medicare Advantage plans also typically include services like dental care and durable medical equipment, such as hearing aids, which are not covered under Original Medicare. Look at what’s covered and compare the premiums, deductibles and coinsurance.

For more information on AEP and OEP, or to learn about Baylor Scott & White Health Plan Medicare Advantage plans, call 1.800.782.5068 (TTY: 711).