How to Switch Medicare Advantage Plans: A Step-by-Step Guide for 2026

This article is for general educational purposes only and is not insurance or medical advice. We are not affiliated with the U.S. government or Medicare. For official information, visit Medicare.gov or call 1-800-MEDICARE. See our Medical & Financial Disclaimer for details.

Unlike home or auto insurance, you can’t switch your Medicare Advantage plan whenever you want. There are specific windows each year, they don’t overlap, and missing them generally means staying in a plan you may have outgrown until the next opportunity. Here’s exactly when you can switch, how to do it without ending up in a gap, and the protections that exist for people who were given wrong information — including one that expires at the end of this year.

The Quick Answer

• Annual Enrollment Period: October 15 – December 7, open to everyone with Medicare, as many changes as you like inside the window
• Medicare Advantage Open Enrollment Period: January 1 – March 31, only if you’re already in a Medicare Advantage plan, and one change only
• Special Enrollment Periods: year-round, but only with a qualifying event — and being given wrong information counts as one
• If you joined Medicare Advantage for the first time at 65: you have a 12-month right to leave that most people never hear about

The Two Main Windows

Annual Enrollment Period (October 15 – December 7)

This is the big one, and it’s open to anyone with Medicare. Inside it you can move in any direction: from Original Medicare into a Medicare Advantage plan, from Medicare Advantage back to Original Medicare, from one Medicare Advantage plan to a different one, or in and out of a standalone Part D drug plan. Whatever you choose takes effect on January 1 of the following year.

You’re also not limited to one decision. CMS enrollment guidance states that where someone submits more than one request, the last enrollment choice — determined by the plan’s receipt date — is the one that becomes effective. That single detail changes how you should treat the deadline. December 7 is the date the plan has to have your request, not the date you have to send it. A form mailed on December 5 that lands on December 9 isn’t a late change, it’s no change at all. Which is why enrolling online or by phone in the final week is meaningfully safer than mailing anything.

Medicare Advantage Open Enrollment Period (January 1 – March 31)

This window runs on different rules. It exists only for people already enrolled in a Medicare Advantage plan, and it’s there as a safety valve for when a plan turns out not to fit once you start using it — the first appointment of the year that reveals your doctor isn’t actually in network, or the first pharmacy visit that reveals your medication sits on a tier you weren’t expecting.

You can either switch to a different Medicare Advantage plan or drop Medicare Advantage entirely and return to Original Medicare, adding a standalone Part D plan if you want one. But you get one change only: Medicare’s guide to enrollment periods is explicit that you can make just one change each year during this window. Changes take effect the first of the month after the plan gets your request.

Because there is no second attempt, this is the one window where confirming your doctors and medications belongs before you submit rather than after. Get it wrong in January and you’ve spent the only move you had until October.

Special Enrollment Periods, and the Two-Month Pattern

Outside the two main windows, you generally can’t switch unless a qualifying event applies. These are the common ones, from Medicare’s list of Special Enrollment Periods:

What happened	How long you have
You move out of your plan’s service area, or somewhere with different options	Begins the month before you move if you tell your plan in advance, otherwise when you move — either way, 2 full months after
You move back to the U.S. after living abroad	2 full months after the month you move back
You leave jail, having kept paying Part A and/or Part B	2 full calendar months after release
You lose other coverage, such as employer insurance	2 full months after the coverage ends
A declared natural disaster or emergency affects your area	2 months

Two things are worth pulling out of that table. The first is the pattern: almost every one of these is two full months. If something on this list happens to you, assume two months and act inside them rather than looking the rule up later.

The second is the moving row. Telling your plan before you move starts the window a month earlier, at no cost and with no downside. It is the only free extra month in the entire Medicare enrollment system, and it exists purely as a reward for making one phone call before the moving truck arrives rather than after.

One more case, which matters for anyone who has lost a doctor mid-year: if you’re notified that there’s a significant change in your plan’s provider network, Medicare lists that among the exceptional circumstances that open a Special Enrollment Period, again with 2 months to move. You may not have to wait for October at all.

And one that has nothing to do with anything going wrong: if a plan rated five stars is sold in your county, the 5-Star Special Enrollment Period lets you move into it once between December 8 and November 30, outside every other window on this page. Medicare lists it among the Special Enrollment Periods linked above. The binding constraint here is availability rather than eligibility — as our guide to star ratings sets out, most counties have no five-star plan to switch into.

If You Were Given Wrong Information

This is the part of the rules almost nobody knows exists, and it’s the part most worth knowing. Medicare treats “you chose this plan because someone told you something untrue” as its own category of qualifying event, and there are several distinct routes.

If you joined a plan, or chose not to join one, because of an error, misrepresentation or inaction by a federal employee or someone authorized to act on the government’s behalf, you get 2 full months after the month you receive notice of the error. Misleading information from a plan representative or a State Health Insurance Assistance Program counselor falls under exceptional circumstances, with the same 2 months. So does being notified of a significant change to your plan’s provider network. And if your plan failed to properly tell you that your other private drug coverage wasn’t as good as Medicare’s, or failed to tell you that you were losing coverage that was, that’s another 2 full months from the month you get notice of the error.

Read those timings carefully, because they share a feature that works in your favor. Most run from when you receive notice of the error, not from when the error was made. The clock may not have started yet on something that went wrong months ago — which is a reason to raise it with 1-800-MEDICARE rather than assuming you’re out of time.

The 2026-only Plan Finder directory protection

There’s one more, and unlike the others it is genuinely temporary. In 2025 the Medicare Plan Finder added a feature showing which doctors are in a plan’s network. CMS acknowledged that some of that directory information may be incorrect, especially in this first year, and created a Special Enrollment Period for people tripped up by it.

It is narrow. Per the CMS notice on this new Plan Finder SEP, all four of these have to be true:

1. You enrolled in the Medicare Advantage plan through the Medicare Plan Finder. CMS is explicit that this SEP is only open to people who relied on incorrect information from Plan Finder — not from a plan’s own website.
2. Your plan’s effective date falls between January 1 and December 1, 2026.
3. You are within the first 3 months of that enrollment.
4. You found your preferred doctor was not in the plan’s provider network.

Two things follow from that list, and both are the kind of detail that gets left out elsewhere. The three-month limit means this is not a protection you can sit on: if you discovered the problem in month five, this particular route has closed, although the misleading-information routes above may still be open to you. And CMS states the SEP is available through 2026 only, so it will not be there next year.

While it lasts, it’s a decent argument for enrolling through Medicare.gov or 1-800-MEDICARE rather than a third-party site. But treat it as a fallback, not as a substitute for calling your doctor’s office and asking whether they take the plan.

The First-Timer’s Safety Net: Your 12-Month Right to Leave

If you joined a Medicare Advantage plan when you were first eligible for Medicare at 65, and within that first year you decide you’d rather have Original Medicare, Medicare gives you a full 12 months from joining to drop the plan. You switch back to Original Medicare automatically, and you get special rights to buy a Medigap policy for a limited time.

That second half is what makes this valuable rather than merely convenient. As covered in our Medicare Advantage vs Medigap comparison, leaving Medicare Advantage does not normally entitle you to a Medigap policy at all — in most states an insurer can underwrite your application and decline it. Inside this trial right, it can’t. A closely related right covers the reverse move: if you dropped a Medigap policy the first time you joined a Medicare Advantage plan, the same 12-month trial period applies to getting Medigap back.

Read the condition carefully, because it’s narrower than it sounds. It’s tied to joining Medicare Advantage when first eligible at 65, and to the first 12 months. It is not a general right to leave Medicare Advantage within a year of joining any plan. But if you are in that first year, it is the single most valuable thing on this page, and it is the only route out that carries the Medigap protection with it.

How to Actually Make the Switch

1. Check your doctors with the doctors, not with the directory. Use the Medicare Plan Finder to compare premiums, star ratings and your medications against each formulary — then phone the offices of the doctors you actually see and ask whether they take that specific plan. CMS has itself acknowledged directory errors; a two-minute call is worth more than any listing.
2. Enroll through official channels where you can. The Plan Finder or 1-800-MEDICARE (1-800-633-4227). Through 2026, this is also what makes the directory protection above available to you at all.
3. Don’t send a disenrollment nobody asked you for. The new enrollment is the action; the exit generally takes care of itself. Our guide to leaving Medicare Advantage sets out when you do and don’t need to contact your plan at all. When you’re moving between two Medicare Advantage plans, say plainly to whoever processes it that this is a switch and let them close the old enrollment. A separate disenrollment sent on your own initiative is an extra moving part in a process that didn’t need one, and it’s how people end up back in Original Medicare by accident.
4. Know your effective date before you submit. AEP changes start January 1. MA OEP and most Special Enrollment Period changes start the first of the month after the plan receives the request. If you’re unsure what has actually been processed, 1-800-MEDICARE can confirm both sides before the date arrives.
5. Keep the paperwork. Save your confirmation and the date you submitted. If something needs correcting later, the date you can prove is the one that counts.

Signs It Might Be Time to Switch

The clearest signal is the network: a doctor or specialist you rely on has left it, or you’re facing repeated prior authorization denials for care you actually need. If you were formally notified of a significant network change, remember you may not have to wait for an enrollment window at all.

Cost is the other common trigger, and it usually shows up at the pharmacy rather than in the premium — a medication that disappeared from the formulary, or moved to a tier that quietly undid whatever the $0 premium was saving you.

Then there’s the slower kind of reason: your priorities changed. That runs in both directions. Some people want more freedom to see specialists and travel without network limits; others want the simplicity of one all-in-one plan instead of juggling Original Medicare, Medigap and Part D separately. Neither is a mistake, and either is a good enough reason to use a window you’re entitled to.

Frequently Asked Questions

Can I switch Medicare Advantage plans more than once a year? Within the Annual Enrollment Period, yes — as often as you like, and the last request the plan receives before December 7 is the one that counts. After that you get one change during the Medicare Advantage Open Enrollment Period if you’re already in a Medicare Advantage plan. Outside those, you need a qualifying Special Enrollment Period.

My doctor left the network in June. Do I have to wait until October? Not necessarily. Being notified of a significant change in your plan’s provider network is listed among the exceptional circumstances that open a Special Enrollment Period, giving you 2 months to move. Call 1-800-MEDICARE and ask about that specifically.

I enrolled through Plan Finder and my doctor isn’t actually in the network. What can I do? If your plan started between January 1 and December 1, 2026, you’re within the first 3 months of enrollment, and you relied on Plan Finder’s own directory rather than a plan website, a Special Enrollment Period is available — but only through 2026.

Do I need to cancel my old plan before joining a new one? For a move between two Medicare Advantage plans, no: the new enrollment closes the old one, and a cancellation you send yourself causes more problems than it solves. If you are leaving Medicare Advantage altogether the mechanics differ slightly, and our guide to disenrolling walks through them. Either way, check with 1-800-MEDICARE rather than mailing a form.

Do I get extra protection if this is my first Medicare Advantage plan? If you joined when first eligible at 65, yes: 12 months to drop it and return to Original Medicare, plus special rights to buy a Medigap policy for a limited time. That Medigap piece is the part worth protecting.

Bottom Line

Switching isn’t something you can do on a whim, but the rules are more forgiving than most people assume — and the forgiveness is concentrated in two places almost nobody looks.

The first is the wrong-information category. Errors by federal staff, misleading claims from a plan representative, and significant network changes all open a two-month window outside the normal calendar, and most of those clocks start when you’re notified rather than when the error happened. The second is the 12-month trial right for anyone who joined Medicare Advantage when first eligible at 65, which is the only reliable way to leave Medicare Advantage and still be guaranteed a Medigap policy.

If neither applies to you, the practical rules are short: compare in October rather than December, call the doctor’s office instead of trusting a directory, and let the new enrollment do the work rather than sending a disenrollment of your own.

Compare and switch plans through the official Medicare Plan Finder, or call 1-800-MEDICARE or your local State Health Insurance Assistance Program (SHIP) for free, unbiased help with the process.

Sources

• Special Enrollment Periods — Medicare.gov. Source for the moving SEP starting a month earlier with advance notice, the 2-month windows, the jail SEP and its premium condition, the federal-employee error and misleading-information SEPs, the significant-network-change SEP, the creditable coverage notification SEPs, the 5-Star Special Enrollment Period running from December 8 to November 30 and usable once, and the 12-month right to drop a first Medicare Advantage plan joined at 65.
• New Special Enrollment Period for Medicare Plan Finder — Centers for Medicare & Medicaid Services. Source for the four conditions of the 2026 directory SEP, the restriction to people who relied on Plan Finder rather than a plan website, and the fact that it is available through 2026 only.
• Understanding Medicare Advantage Plans — Medicare.gov. Source for disenrollment happening automatically when you return to Original Medicare and join a separate drug plan.
• Understanding Medicare Advantage & Medicare Drug Plan Enrollment Periods — Medicare.gov. Source for the one-change limit during the Medicare Advantage Open Enrollment Period.
• CY 2026 Medicare Advantage and Part D Enrollment and Disenrollment Guidance — Centers for Medicare & Medicaid Services. Source for multiple elections during the Annual Enrollment Period and for the last choice, by plan receipt date, being the one that takes effect.
• Joining a plan — Medicare.gov. Source for the October 15 – December 7 and January 1 – March 31 dates and their effective dates.

All dates and rules on this page were checked against the sources above on September 16, 2026.

Disclaimer: Enrollment rules, windows, and protections mentioned in this article reflect 2026 guidelines from the Centers for Medicare & Medicaid Services (CMS) and are subject to change. Always confirm current details directly with Medicare.gov, 1-800-MEDICARE, or a licensed agent before making a decision.