Disenroll From a Medicare Advantage Plan: Windows, Steps, and Coverage

You can disenroll from a Medicare Advantage plan only during specific windows set by Medicare, not on demand. The four opportunities are the Annual Enrollment Period each fall, the Medicare Advantage Open Enrollment Period from January through March, a 12-month trial right if you joined at 65, and Special Enrollment Periods triggered by qualifying life events. Once you know which window applies, you can disenroll from a Medicare Advantage plan by calling Medicare directly, contacting your plan, or simply enrolling in the coverage that will replace it.

When You Can Leave

Annual Enrollment Period: October 15 to December 7

This is the widest window. Between October 15 and December 7, you can drop your Medicare Advantage plan and return to Original Medicare, switch to a different Medicare Advantage plan, or add or drop prescription drug coverage.¹ Whatever change you make takes effect January 1 of the following year.

If you go back to Original Medicare and want prescription coverage, sign up for a standalone Part D plan in the same window. Your Medicare Advantage drug coverage ends when the plan does.

Medicare Advantage Open Enrollment Period: January 1 to March 31

If you’re enrolled in a Medicare Advantage plan on January 1, you get a second chance between January 1 and March 31.² You can make one change: switch to a different Medicare Advantage plan, or drop it and return to Original Medicare. If you return to Original Medicare, you can also enroll in a standalone Part D plan.³

The one-change limit is firm. Use it, and you’re locked in until the next Annual Enrollment Period. The change takes effect the first day of the month after your plan receives your request, which is faster than the January 1 effective date from the fall window.³

Boundary: this window is only for people already in Medicare Advantage. You can’t use it to move from Original Medicare into a Medicare Advantage plan, and you can’t use it to switch between standalone Part D plans if you’re already on Original Medicare.³

First-Year Trial Right

If you joined a Medicare Advantage plan when you first became eligible for Medicare at 65, you have 12 months to change your mind. During that year you can drop the plan and return to Original Medicare at any time.⁴ This is a separate right, not your “one change” during the January–March window.

The trial right also gives you guaranteed issue rights for a Medigap policy. Insurers cannot deny you a policy or charge more for health reasons if you apply within the 12 months.⁴ The same protection applies if you dropped an existing Medigap policy to try Medicare Advantage for the first time and want that Medigap coverage back within 12 months. After 12 months, those protections disappear in most states.

Special Enrollment Periods

Certain life events open a Special Enrollment Period outside the scheduled windows. The most common ones that let you leave Medicare Advantage:

You move outside your plan’s service area. You can switch to a plan available at your new location or return to Original Medicare. If your new address is still in the plan’s service area, you can switch plans but generally can’t use the move as a reason to drop Medicare Advantage entirely.⁴
You lose employer coverage, COBRA, or other creditable coverage. You have two full months after the month your coverage ends to make a change.⁴
You move into, live in, or move out of a skilled nursing facility, long-term care hospital, psychiatric facility, or similar institution. While you live there, you can change plans once a month; after you leave, you have two months.
You gain or lose Medicaid eligibility or qualify for Extra Help with Part D costs.
Your plan has failed to reach a three-star quality rating for three consecutive years, letting you switch to a higher-rated plan. Medicare typically notifies affected members.

How to Submit the Request

You have three practical options.

The most direct is calling 1-800-MEDICARE (1-800-633-4227), available 24 hours a day, seven days a week. A representative will verify your identity, confirm your plan, and process the disenrollment.⁵ A confirmation letter should arrive by mail about a week after the disenrollment processes through Medicare’s systems.⁶

You can also contact your plan directly, by phone, by signed written notice sent through mail or fax, or in some cases through the plan’s website.⁷ Whichever route you take, the plan must send you written confirmation of the disenrollment and its effective date within ten calendar days.⁵

The third option is simplest: enroll in the plan you’re switching to. Signing up for a new Medicare Advantage plan or, if you’re going back to Original Medicare, a standalone Part D plan, automatically disenrolls you from the old one. No separate cancellation is required.

What Happens to Your Drug Coverage

Most Medicare Advantage plans bundle prescription drug coverage. When you leave, that coverage leaves with the plan. If you want to keep prescription benefits, sign up for a standalone Part D plan in the same enrollment window you use to disenroll.²

Watch the 63-day rule. Go 63 days or more without creditable drug coverage and you’ll owe a permanent late enrollment penalty when you eventually pick up Part D. The penalty is 1% of the national base beneficiary premium for every month you were uncovered. In 2026 that base premium is $38.99, so each uncovered month adds about $0.39 to your monthly premium.⁸ A 14-month gap works out to roughly $5.50 extra per month, for as long as you have Part D. The penalty is recalculated each year as the base premium changes.

Medigap Access After You Leave

This is the piece most people underestimate. Original Medicare has no out-of-pocket maximum, so most people returning from Medicare Advantage want a Medigap supplement. Whether you can get one depends almost entirely on when you disenroll.

Inside the 12-month trial period described above, federal law guarantees you the right to buy a Medigap policy without medical underwriting.⁴ A handful of other situations also carry guaranteed issue rights, including your plan leaving your area, employer coverage ending, and cases where a plan misled you about its benefits.

Outside those situations, the picture changes sharply. In most states, Medigap insurers can deny your application, impose waiting periods for pre-existing conditions, or charge higher premiums based on your health history. Only a handful of states, including Connecticut, Massachusetts, and New York, require Medigap insurers to accept all applicants year-round regardless of health. If you live elsewhere and have developed health conditions while in Medicare Advantage, affordable Medigap coverage after the trial period may be hard or impossible to get. This is the single biggest reason to think through disenrollment before you file the request.

When Your New Coverage Starts

The effective date depends on the window you used:

Annual Enrollment Period: new coverage begins January 1.¹
Medicare Advantage Open Enrollment Period: new coverage begins the first day of the month after your plan receives the request.⁵
Special Enrollment Periods: effective dates vary by the qualifying event, but most changes also take effect the first of the following month.

If you enroll in a new plan while still a member of your current one, CMS handles the transition automatically, with no gap and no duplication.⁵ Records can take up to a month to fully update, though, so let your providers’ billing offices know about the switch to avoid claims being sent to the wrong payer.

1
Medicare. Open Enrollment
2
Medicare. Joining a Plan
3
Medicare.gov. Fact Sheet – Understanding Medicare Advantage and Medicare Drug Plan Enrollment Periods
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Medicare. Special Enrollment Periods
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Centers for Medicare & Medicaid Services (CMS). CY 2024 MA Enrollment and Disenrollment Guidance
6
Social Security Administration. Disenrollment From Medicare Advantage (MA) and 1876 Cost Plans
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Medicare. What if I Want to Switch, Drop, or Rejoin Drug Coverage?
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Medicare. Avoid Late Enrollment Penalties