Most of the year, the answer is no
It is worth saying plainly, because people spend a lot of time looking for a door that is not there. From April through the middle of October, if your circumstances have not changed, you cannot switch Medicare Advantage or Part D plans. Not because of paperwork, and not because somebody is being difficult. The windows are simply closed.
What follows is which window opens which door.
Which switch, which window
| What you want to do | When you can do it |
|---|---|
| Change from one Medicare Advantage plan to another | AEP (Oct 15 to Dec 7), MA OEP (Jan 1 to Mar 31), or a Special Enrollment Period |
| Change from one Part D plan to another | AEP, or a Special Enrollment Period |
| Join Medicare Advantage from Original Medicare | AEP, or a Special Enrollment Period. Not during MA OEP |
| Leave Medicare Advantage for Original Medicare | AEP, MA OEP, or a Special Enrollment Period |
| Change or buy a Medicare Supplement | Any month, but subject to medical underwriting outside a guaranteed issue situation |
| Drop Part D entirely | AEP. A late enrollment penalty applies if you rejoin later |
The switch that is hard to reverse
Four of those moves are ordinary. One is a one-way door in this state, and it is the fourth row.
Leaving Medicare Advantage for Original Medicare is permitted and simple. What is neither permitted nor simple is the second half of that plan, which is getting a Medicare Supplement to sit on top. Original Medicare alone has no out-of-pocket maximum, so almost nobody wants to be there without one.
Medigap is regulated by Arkansas rather than by Medicare, and Arkansas gives you one guaranteed window: six months from when you are 65 and enrolled in Part B. After that, absent a specific guaranteed issue situation, a carrier can ask about your health and say no. There is no birthday rule here and no annual do-over. Roughly a dozen states have one. This is not one of them.
If you are leaving Advantage, do it in this order. Apply for the Medicare Supplement. Get a written approval. Then submit the disenrollment from the Advantage plan. People who do it the other way around and get declined in January end up on Original Medicare with an uncapped 20% coinsurance share, and the next chance to change anything is the following October.
There are situations where the Medigap door is held open for you. Your plan leaving your county gives you a guaranteed issue right. So does involuntarily losing employer coverage. So does a trial right if you joined Medicare Advantage when you first became eligible and want out within the first twelve months. If any of those apply, this is the moment to use them, because they do not come around again.
Three things to check before any switch
In this order, because they are ranked by how often they turn out to be the problem.
Your medications, at the tier the new plan puts them on
Not whether the drug is covered. Which tier. A plan can technically cover everything you take and still be far more expensive than what you have, because tier placement drives the copay and formularies are reorganized every year. Price the full year on your actual prescription list at your actual pharmacy, since preferred pharmacy networks change the number again.
Your doctors, confirmed by your doctors
Plan directories are frequently out of date, and the answer that matters is whether the provider will be in network for the specific plan in the coming plan year. Call the billing office at the practice and ask by plan name. Baptist Health, CHI St. Vincent, UAMS and Conway Regional do not all participate in the same networks, and participation is renegotiated annually.
Total annual cost, not the premium
A plan with no premium is not free, it has moved the cost into copays and coinsurance. Add premium, deductible, expected copays, and drug costs across a full year for each option. For someone with a chronic condition, the cheaper premium routinely loses.
How to switch without creating a gap
This part is easier than people fear, provided you do not help.
Never call to cancel your old plan. Enrolling in a new Medicare Advantage or Part D plan automatically disenrolls you from the old one the day the new coverage starts. The handoff is built to happen on its own and it generally does. Cancelling the old plan yourself, before the new enrollment is confirmed, is the main way people manufacture a gap that did not need to exist.
Two exceptions. If you are dropping Medicare Advantage to return to Original Medicare, you do submit a disenrollment, and it should follow your Medigap approval rather than precede it. If you are dropping a Medigap policy, you cancel that yourself, and again only after the new coverage is confirmed in writing.
Keep the confirmation number and watch for the new plan's card and welcome packet. If nothing arrives within about three weeks, call the plan rather than assuming it went through.
When switching is not the answer
Some of what sends people looking for a new plan is not a plan problem. Deductibles reset on January 1, so an expensive first pharmacy visit of the year is normal. Prior authorization delays often look like denials when they are paperwork in progress. A single surprise bill is worth understanding before it costs you your one annual change.
Worth switching over: a daily medication that moved to a tier you cannot sustain, a provider you will not leave who has gone out of network, or a service you use regularly that the plan does not cover. Those are real. If what you have is one confusing bill from the second week of January, get it explained first.
Lancaster Cook is an independent agent in Little Rock, AHIP certified, Arkansas license #8021079. Reviewing a switch before you make it costs nothing, and on the Advantage-to-Original move it is worth doing.