Medicare Advantage open enrollment: the January to March window

If you are already in a Medicare Advantage plan, you may use this period to switch to a different Advantage plan, or to leave Advantage entirely and return to original Medicare with a stand-alone drug plan. You get one change. Once used, the window is closed for you until the fall.

What you cannot do is the reverse. Someone on original Medicare cannot use the January to March period to join an Advantage plan, because the fall annual enrollment period is the door for that. Confusing the two directions is the most common reason a call in February ends in disappointment.

Leaving an Advantage plan to return to original Medicare feels like a reset. It is not. Unless you are using the first-year trial right, or you live in a state with its own protections, buying a Medigap policy after you leave means answering health questions and possibly being declined.

That produces a specific, avoidable disaster: a person drops the Advantage plan in February, applies for a supplement in March, is declined in April, and is left with original Medicare and no cap on cost sharing. Before anyone leaves an Advantage plan, the supplement application should be the deciding factor, not an afterthought.

Start in December, not March. Confirm whether your doctors and preferred hospital are in network for the coming plan year, since networks change on January 1 and the plan you liked last year may not be the same one now. Check the drug formulary at the same time, because an Advantage plan without your medications is not a saving.

Then decide what you are actually fixing. If the premium was fine but the network failed, another Advantage plan may solve it. If the problem was prior authorizations and referral rules, the answer is probably original Medicare plus a supplement, and that requires knowing your underwriting position first.