➤ When is the Medicare Advantage Open Enrollment Period?
January 1 through March 31 every year. It is open only to people already enrolled in a Medicare Advantage plan, and it allows one change. Your new coverage begins the first day of the month after the plan receives your enrollment.
➤ What is the difference between AEP and Medicare Advantage Open Enrollment?
The Annual Enrollment Period runs October 15 to December 7, is open to everyone with Medicare, and allows any combination of joining, switching or dropping Advantage and Part D plans. The Medicare Advantage Open Enrollment Period runs January 1 to March 31, is open only to current Advantage members, and allows one change — either switching Advantage plans or returning to Original Medicare with a Part D plan.
➤ Can I join a Medicare Advantage plan during MA Open Enrollment?
Not from Original Medicare. The Medicare Advantage Open Enrollment Period is for people already in an Advantage plan who want to change or leave it. Moving from Original Medicare into Advantage requires the Annual Enrollment Period or a Special Enrollment Period you qualify for.
➤ How many times can I change plans during MA Open Enrollment?
Once. You get a single change during the January to March window, and once it takes effect you are locked in until the next Annual Enrollment Period unless a Special Enrollment Period applies. Check the network and drug formulary carefully before you submit, because you will not get a second attempt.
➤ When does coverage start if I switch during MA Open Enrollment?
The first day of the month after the plan receives your enrollment. So a change made in January generally starts February 1, and one made in March starts April 1. This is different from an AEP change, which always starts January 1 regardless of when in the window you enrolled.
➤ Can I get a Medicare Supplement during MA Open Enrollment?
You can apply, but it is not guaranteed. Outside your initial six-month Medigap window or a specific guaranteed-issue situation, most states allow insurers to use medical underwriting and decline you based on your health. Returning to Original Medicare is the easy part; getting a supplement to sit on top of it is the part that is not automatic.
➤ What if my plan was discontinued?
You get a Special Enrollment Period running December 8 through the last day of February, which is separate from MA OEP and has its own rules. Losing coverage this way also opens a 63-day guaranteed-issue right to buy certain Medicare Supplement policies without health questions, measured from the day your coverage ends.
➤ What is the 5-star Special Enrollment Period?
If Medicare rates a plan in your county five stars, you can switch into it once between December 8 and November 30, outside any other enrollment window. Five-star plans are not available in every county, but where one exists this is the most flexible enrollment right available and very few people use it.
➤ Can I change my Part D plan during MA Open Enrollment?
Only as part of leaving a Medicare Advantage plan. If you drop Advantage and return to Original Medicare during this window, you can add a standalone Part D plan at the same time. If you are already on Original Medicare, you cannot change Part D plans between January and March — that requires the Annual Enrollment Period.
➤ What if I miss every enrollment period?
Your current coverage continues as it is, and the next window is the Annual Enrollment Period beginning October 15. Before assuming you have missed everything, check whether you qualify for a Special Enrollment Period — moving, losing other coverage, entering a nursing facility, or becoming eligible for Medicaid or Extra Help all open one, and they are more common than most people realize.