To get out of a Medicare Advantage plan, you disenroll during one of Medicare’s enrollment windows by calling 1-800-MEDICARE, contacting your plan directly, or simply enrolling in different coverage. Your protection reverts to Original Medicare automatically once the disenrollment takes effect. The paperwork is the easy part. The harder questions are whether you can still buy a Medigap policy to cover what Original Medicare doesn’t, and whether you’ll owe a lifetime penalty for going without drug coverage.
When You’re Allowed to Leave
Medicare doesn’t let you drop an Advantage plan on any random Tuesday. You need to act inside one of three windows.
The broadest is the Fall Open Enrollment Period, October 15 through December 7. Anyone with Medicare can switch back to Original Medicare, move to a different Advantage plan, or add a standalone Part D drug plan. Changes take effect January 1.1Medicare. Open Enrollment
The Medicare Advantage Open Enrollment Period runs January 1 through March 31 and is only for people already in an Advantage plan on January 1. You get one change: switch to a different Advantage plan, or drop your plan and return to Original Medicare (with the option to add a standalone Part D plan). Coverage starts the first day of the month after your plan processes the request.2Medicare.gov. Understanding Medicare Advantage and Medicare Drug Plan Enrollment Periods One change only. If you switch plans in January and regret it in February, this window won’t help you switch again.
A Special Enrollment Period opens when something specific happens in your life: you move out of your plan’s service area, lose employer coverage, qualify for Medicaid, or your plan leaves Medicare. You generally have 60 days around the event to make a change.3Medicare. Your Health Plan Options Miss that window and you’re usually locked in until the next Fall Open Enrollment.
There’s also a narrow five-star SEP. If a plan with a perfect five-star quality rating is sold in your area, you can switch to it once between December 8 and November 30 of the following year. It only works for moving into a five-star plan, not for returning to Original Medicare.4Medicare. Medicare and You Handbook 2026
Three Ways to Disenroll
Pick the method that matches where you’re going.
Call 1-800-MEDICARE
The most direct route back to Original Medicare is calling 1-800-MEDICARE (1-800-633-4227; TTY 1-877-486-2048). When the automated system picks up, say “Agent” and tell the representative you want to disenroll from your Advantage plan. They verify your identity, confirm the plan you’re leaving, and process the request. A confirmation letter arrives within about a week.5Social Security Administration. Disenrollment from Medicare Advantage (MA) and 1876 Cost Plans
Contact Your Plan
You can call your Advantage plan and ask them to disenroll you. The plan must send a written notice within 10 calendar days confirming the request, the effective date, and any restrictions that apply while the request processes.6Centers for Medicare & Medicaid Services. CY 2024 MA Enrollment and Disenrollment Guidance Some plans accept a paper disenrollment form; it asks for your name, Medicare number, date of birth, and signature.7Centers for Medicare & Medicaid Services. Medicare Advantage Enrollment and Disenrollment Guidance Appendices and Exhibits
Enroll in Different Coverage
If you’re moving to a different Advantage plan, enrolling in the new one automatically disenrolls you from the old. No separate cancellation. The same happens if you enroll in a standalone Part D plan while on Original Medicare: the Part D enrollment triggers the disenrollment from your Advantage plan.
What Happens to Your Coverage
Once disenrollment takes effect, you’re back on Original Medicare automatically. Part A covers hospital care, Part B covers outpatient services, and your red, white, and blue Medicare card still works. You don’t re-enroll in anything.8Medicare. What Original Medicare Covers You can see any doctor or hospital nationwide that accepts Medicare, with no network restrictions.
Your Advantage plan covers you right up to the effective date, so there’s no gap. If you disenrolled during Fall Open Enrollment, Original Medicare picks up January 1. If you used the January–March window, it picks up the first of the month after processing.2Medicare.gov. Understanding Medicare Advantage and Medicare Drug Plan Enrollment Periods
One thing to flag before you move on: Original Medicare does not include prescription drug coverage. If your Advantage plan included drugs, you need to enroll in a standalone Part D plan at the same time or risk a permanent penalty (more on that below).
The Medigap Question That Can Trap You
This is the single biggest issue people miss when leaving an Advantage plan. Original Medicare has no annual cap on what you can owe out of pocket. A Medigap (Medicare Supplement) policy fills those gaps, covering the Part A and B deductibles, the 20% coinsurance on outpatient services, and other costs. Whether an insurer will sell you one, and at what price, depends almost entirely on timing.
Your Medigap Open Enrollment Period runs for six months starting the month you turn 65 and have Part B. During that six-month window, insurers must sell you any policy they offer at the standard price regardless of your health. After it closes, insurers in most states can use medical underwriting to deny you or charge more based on pre-existing conditions.9Medicare. Get Ready to Buy
The 12-Month Trial Right
Two protections let you get Medigap on a guaranteed-issue basis after that initial window:
- If you joined an Advantage plan when you first became eligible for Medicare at 65 and leave within the first 12 months, you can buy any Medigap policy from any insurer with no underwriting.10Medicare. Learn How Medigap Works
- If you dropped a Medigap policy to try an Advantage plan for the first time and return within 12 months, you can get your old Medigap policy back from the same insurer. If that specific policy is no longer sold, certain other plans are available on a guaranteed-issue basis depending on your state.10Medicare. Learn How Medigap Works
You also get guaranteed-issue rights in involuntary situations: your Advantage plan leaves Medicare, stops serving your area, or fails to meet its obligations. You have 63 days from the end of that coverage to apply, and the insurer can’t deny you or charge more based on health.9Medicare. Get Ready to Buy
If you’ve been in an Advantage plan for more than a year and are leaving voluntarily, you probably don’t qualify for any of these protections. Insurers can screen your health and either deny coverage or set premiums well above the standard rate. For people with significant health conditions, that is often the real barrier to leaving an Advantage plan. A handful of states have “birthday rule” protections that give Medigap policyholders an annual window to switch without underwriting, but the rules vary and don’t apply everywhere.
The Part D Penalty Trap
If your Advantage plan included drug coverage and you drop it without immediately enrolling in a standalone Part D plan, you face a permanent late enrollment penalty when you eventually sign up. Medicare calculates it at 1% of the national base beneficiary premium ($38.99 in 2026) for every full month you went without creditable drug coverage.11Medicare. Avoid Late Enrollment Penalties
It adds up. Twenty-four months without coverage adds roughly $9.36 per month on top of whatever Part D plan you eventually buy, for as long as you have Part D. For most people that’s life. Even if you take no prescriptions today, enrolling in a low-cost Part D plan when you leave your Advantage plan is almost always worth it.12Medicare. How Much Does Medicare Drug Coverage Cost
What Original Medicare Will Cost You in 2026
Before you commit, know what you’re walking into. Advantage plans cap your annual out-of-pocket spending. Original Medicare does not, unless you add a Medigap policy.
The standard Part B monthly premium is $202.90 in 2026. Higher earners pay more: if your modified adjusted gross income on your 2024 tax return exceeded $109,000 (individual) or $218,000 (joint), monthly premiums range from $284.10 to $689.90 depending on the bracket.13Medicare. Fact Sheet – 2026 Medicare Costs
The Part B annual deductible is $283. After meeting it, you typically pay 20% of the Medicare-approved amount for most outpatient services, with no ceiling. The Part A inpatient hospital deductible is $1,736 per benefit period, and a benefit period resets after you’ve been out of the hospital for 60 consecutive days. Multiple hospitalizations in one year can each trigger a new deductible.14Centers for Medicare & Medicaid Services. 2026 Medicare Parts A and B Premiums and Deductibles
For a standalone Part D plan, the maximum annual deductible any plan can charge in 2026 is $615, though many plans set theirs lower or waive it. Monthly premiums vary by plan and region. After you’ve spent $2,100 out of pocket on covered drugs, catastrophic coverage kicks in and you pay nothing for the rest of the year.12Medicare. How Much Does Medicare Drug Coverage Cost
Put the pieces together before you disenroll. Price out a Medigap policy and confirm you can get one. Line up a Part D plan so the switch takes effect the same month your Advantage plan ends. Done in that order, leaving an Advantage plan is a clean handoff. Done out of order, it can mean higher premiums for life or no supplemental coverage at all.