You can switch from Medicare Advantage back to Original Medicare during two specific windows each year, and the process itself takes a single phone call. The bigger challenge is timing your switch correctly and making sure you don’t end up with gaps in drug coverage or supplemental insurance. Here’s exactly how to do it.
When You Can Make the Switch
There are two enrollment periods that allow you to drop a Medicare Advantage plan and return to Original Medicare:
- Annual Enrollment Period (October 15 through December 7): You can switch from Medicare Advantage to Original Medicare, and the change takes effect January 1. You can also sign up for a standalone Part D drug plan at the same time.
- Medicare Advantage Open Enrollment Period (January 1 through March 31): If you’re currently in a Medicare Advantage plan, you can drop it and return to Original Medicare. You’re allowed one change during this window. The switch takes effect the first day of the month after your plan receives the request.
The fall Annual Enrollment Period is generally the better time to make this move. It gives you more flexibility to line up a Part D drug plan and, if you want one, a Medigap supplemental policy with a clean January 1 start date. The January through March window works too, but coordinating supplemental coverage on a mid-year timeline can be trickier.
How to Disenroll Step by Step
The most straightforward way to leave your Medicare Advantage plan is to call 1-800-MEDICARE (1-800-633-4227). TTY users can call 1-877-486-2048. When you reach the automated system, select your language, then say “Agent” when the introduction finishes. Tell the agent you want to disenroll from your Medicare health plan, and they’ll transfer you to a representative who handles disenrollments.
Have the following information ready before you call:
- Your full name
- Your Medicare number from your red, white, and blue Medicare card
- Your date of birth
- One additional piece of identifying information, such as your Social Security number, address, or phone number on file
The representative will verify which plan you’re enrolled in, confirm you want to leave it, and process the disenrollment. You should receive a confirmation letter in the mail within about a week once Medicare’s systems process the change. There is no paper form you need to fill out or mail in.
If you’re enrolled in a Medicare Medical Savings Account plan or an 1876 Cost Plan, the process is slightly different. You’ll need to contact your plan directly to disenroll rather than calling 1-800-MEDICARE.
Don’t Forget Prescription Drug Coverage
This is the detail most people overlook. Medicare Advantage plans typically bundle prescription drug coverage. When you drop your Advantage plan, that drug coverage disappears. Original Medicare does not include prescription drug coverage on its own, so you’ll need to enroll in a standalone Medicare Part D plan to avoid a gap.
If you switch during the Annual Enrollment Period (October 15 through December 7), you can sign up for a Part D plan at the same time, and both changes kick in January 1. If you switch during the January through March window, you can also join a Part D plan at that time.
Timing matters here because going without creditable drug coverage for 63 or more continuous days triggers a late enrollment penalty. That penalty adds a surcharge to your Part D premium for as long as you have the plan. The simplest way to avoid it is to have your Part D plan start the same month your Advantage coverage ends.
The Medigap Question
Original Medicare has no out-of-pocket maximum. That means if you have a major hospitalization or a series of expensive treatments, your 20% coinsurance on Part B services adds up with no cap. This is why most people on Original Medicare buy a Medigap (Medicare Supplement) policy to cover some or all of those costs.
Here’s the catch: getting a Medigap policy after you’ve been on Medicare Advantage can be difficult. When you first enroll in Medicare Part B at age 65, you get a six-month Medigap Open Enrollment Period during which insurers must sell you any policy regardless of your health. Once that window closes, federal law does not guarantee you can buy a Medigap policy. Insurers in most states can deny you coverage or charge higher premiums based on your health history.
Some states offer stronger protections. A handful require insurers to sell Medigap policies year-round regardless of health status, and several others have “birthday rules” that give you an annual window to switch Medigap plans. Check with your state insurance department to find out what rights you have, because this varies significantly by state and can determine whether switching back to Original Medicare is financially practical for you.
If you’ve been in a Medicare Advantage plan for less than 12 months, you may have a guaranteed issue right to buy a Medigap policy. This is sometimes called a “trial right” for people who tried Medicare Advantage and want to return. The specifics depend on your situation and state, so it’s worth confirming your eligibility before you finalize the switch.
What Changes When You’re Back on Original Medicare
The biggest practical difference is provider access. On Original Medicare, you can see any doctor or visit any hospital in the country that accepts Medicare, with no network restrictions. You don’t need referrals to see specialists in most cases. If you’ve been frustrated by network limitations, prior authorization requirements, or needing your primary care doctor to sign off before seeing a specialist, that goes away.
On the cost side, the tradeoffs shift. Many Medicare Advantage plans have low or zero monthly premiums beyond the standard Part B premium, plus they include an annual out-of-pocket maximum. Original Medicare has no out-of-pocket cap, and you’ll likely be paying premiums for both a Medigap policy and a standalone Part D plan. For some people, the monthly costs on Original Medicare end up higher. For others, especially those with complex medical needs or who travel frequently, the unrestricted access and predictable cost-sharing through Medigap make it the better value.
Your Medicare Advantage plan’s extra benefits, like dental, vision, hearing, or gym memberships, also end when you disenroll. Original Medicare does not cover routine dental or vision care, so you’d need to arrange separate coverage for those if they matter to you.
A Practical Timeline for Switching
If you’re planning to switch, the smoothest approach is to start preparing in September or early October, before the Annual Enrollment Period opens. Research standalone Part D plans in your area using Medicare’s plan finder tool at Medicare.gov. Check whether Medigap policies are available to you given your age, health, and state. Compare monthly costs for the combination of Part B premium, Medigap premium, and Part D premium against what you’re currently paying.
Once the enrollment period opens on October 15, call 1-800-MEDICARE to disenroll from your Advantage plan and separately enroll in a Part D plan. If you’re buying a Medigap policy, contact the insurer directly to start that application. Aim to have everything submitted well before the December 7 deadline so there’s time to resolve any issues. Your new coverage starts January 1, and your Advantage plan ends December 31.
If you’re using the January through March window instead, keep in mind that your coverage change takes effect the first of the month after your plan processes the request. You’ll want to have your Part D enrollment lined up to start on the same date to avoid any gap in drug coverage.