Switching from Medicare Advantage to Original Medicare

Not everyone who leaves a Medicare Advantage plan is adding a Medigap policy. Some people simply want to go back to Original Medicare on its own — no network, no bundled extras, just Part A and Part B the way Medicare was originally set up. This is generally a more straightforward switch than adding Medigap, since Original Medicare doesn't use medical underwriting. Here is what the process involves and what changes once you're back on it.

When you can switch

You have two windows for this move. The first is the Annual Enrollment Period, October 15 through December 7, when anyone can drop Medicare Advantage and return to Original Medicare for the following plan year, effective January 1. The second is the Medicare Advantage Open Enrollment Period, January 1 through March 31, available only to people who are already enrolled in a Medicare Advantage plan as of January 1. During that window you're allowed one change: you can switch to a different Medicare Advantage plan, or you can drop Medicare Advantage entirely and return to Original Medicare. Outside these two windows, you'd generally need to qualify for a Special Enrollment Period tied to a specific event.

What changes once you're back on Original Medicare

The most immediate difference is provider access. Medicare Advantage plans typically route your care through a network and often require referrals to see a specialist. Original Medicare doesn't work that way — if a doctor or hospital accepts Medicare, you can see them directly, in any state, without a referral. Billing changes too. Under Medicare Advantage, your plan handles claims and you generally pay a fixed copay at the time of service. Under Original Medicare, Part B typically covers 80% of the approved amount for covered services after you meet your deductible, and you're responsible for the rest unless you have supplemental coverage. There's also no annual out-of-pocket maximum built into Original Medicare on its own, which is one of the main reasons people who make this switch often look at a Medigap policy separately, or budget more deliberately for the 20% Original Medicare doesn't cover.

You'll likely want a Part D plan

Most Medicare Advantage plans bundle in prescription drug coverage. Original Medicare does not include drug coverage at all — Part A and Part B cover hospital and medical care, not prescriptions. If you're switching away from Advantage, you should enroll in a stand-alone Part D plan at the same time, unless you already have creditable drug coverage from another source, such as an employer plan. Going without any drug coverage for an extended stretch after you're Medicare-eligible can lead to a late enrollment penalty added to your Part D premium later, so this isn't a step to skip or delay.

What doesn't change

Your Medicare number stays the same, and your Part A and Part B coverage continues without interruption — you're not re-enrolling in Medicare itself, only changing how the rest of your coverage is structured. Extra benefits that some Advantage plans include, such as dental, vision, or hearing allowances, end when you leave the plan, since those aren't part of Original Medicare.

Consider your out-of-pocket exposure

Because Original Medicare on its own doesn't cap what you could owe in a given year, it's worth thinking through what happens if you have a hospital stay or a run of specialist visits. Some people are comfortable covering that 20% coinsurance out of pocket, or have retiree coverage or another secondary policy that helps with it. If you don't, a Medigap policy is the more common way to manage that gap, though it comes with its own enrollment timing and, outside certain windows, medical underwriting. That's a separate decision from the one covered here, but it's worth having in mind before you finalize the switch, not after.

If you're thinking about this switch, it helps to walk through your specific situation with someone who can check your current plan, your prescriptions, and your timing before you make a change.