Can I switch from Medicare Advantage to a Medicare Supplement?
In short, yes — but the order of steps matters just as much as the timing.
Switching from Medicare Advantage to a Medicare Supplement means returning to Original Medicare (Parts A and B) and applying for a Supplement (also known as Medigap) policy. Outside your one-time Medigap Open Enrollment Period, insurers can review your health history and may charge higher premiums or deny coverage altogether. You'll also need a standalone Part D drug plan — but when you add it matters. Getting the sequence wrong can leave you without coverage.
Common Mistakes to Avoid When Switching from Medicare Advantage to a Supplement
- Missing the enrollment window. Changes must happen during specific periods. If you miss them, you may have to wait until the next window opens.
- Assuming automatic acceptance. Outside your Medigap Open Enrollment Period, insurers can deny Supplement coverage or charge you more based on your health.
- Dropping your plan too soon. Leaving your Medicare Advantage plan without confirming your eligibility for a Supplement can limit your options.
- Enrolling in Part D at the wrong time. Signing up for a Part D drug plan automatically cancels your Medicare Advantage plan. Don't do this until your Supplement is approved.
What Most People Don't Realize
Your Medigap Open Enrollment Period is a one-time, six-month window that begins the first month you enroll in Medicare Part B and are 65 or older. If you chose Medicare Advantage during this time, your guaranteed opportunity to enroll in Supplement coverage may have already ended.
Understanding Medicare Advantage and Medicare Supplement Coverage
Medicare Advantage (Part C) is an all-in-one plan purchased from a private insurer. It bundles your hospital, medical, and often drug coverage, plus extra benefits. Premiums are usually lower, and you have a network of providers.
A Medicare Supplement (Medigap) plan works alongside Original Medicare (Parts A and B). It helps cover out-of-pocket costs like copays, coinsurance, and deductibles. You pay a higher monthly premium, but you can see any doctor who accepts Medicare and typically face fewer medical bills.
The right coverage depends on your health needs, your budget, and how you prefer to manage your care.
How to Make the Switch from Medicare Advantage to a Medicare Supplement
Follow these steps to transition from Medicare Advantage to a Supplement plan. The order of these steps is critical to avoid gaps in coverage.
Step 1: Confirm Your Enrollment Window
You can only change your Medicare coverage during certain periods:
- Medicare Advantage Open Enrollment Period (OEP): Jan. 1 – March 31
- You may switch to a different Medicare Advantage plan or return to Original Medicare.
- One change is allowed, and new coverage begins the first of the following month.
- Medicare Annual Enrollment Period (AEP): Oct. 15 – Dec. 7
- Plan changes take effect Jan. 1.
- Special Enrollment Periods (SEPs)
- Triggered by qualifying life events, such as moving or losing other coverage.
At the same time, confirm if you're still in your Medigap Open Enrollment Period. This determines whether you'll have guaranteed enrollment when you apply for a Supplement.
Step 2: Apply for a Supplement Plan First — Before Making Any Other Changes
Do not cancel your Medicare Advantage plan before you’re approved for a Supplement plan.
Apply for a Supplement while your Medicare Advantage plan is still active. If your application is delayed or denied after you've already dropped your current plan, you could end up without coverage.
Supplement plans are standardized by letter (A–D, F, G, and K–N). Plans with the same letter offer the same benefits regardless of insurer — price is the only difference between plans with the same letter.
Outside your Medigap Open Enrollment Period, insurers will ask questions about your health. Your answers may affect your premium or approval.
Step 3: Wait for Approval Before Taking Further Action
After submitting your Supplement application, wait for written confirmation of approval before making any other changes.
Do not enroll in a standalone Part D drug plan yet. Enrolling in Part D automatically cancels your Medicare Advantage plan, including your drug coverage. Doing this before your Supplement is approved puts you at risk of losing your current coverage before your new coverage begins.
Step 4: Enroll in a Standalone Part D Drug Plan
Once your Supplement is approved, it’s important to enroll in a Part D plan, since Supplement plans don't include prescription drug coverage. Doing this will automatically replace your Medicare Advantage plan — you do not need to cancel it separately.
Check the drug plan's formulary to ensure your medications are covered and align your Part D and Supplement start dates to avoid coverage gaps. Although you should wait to enroll in a Part D plan until after your Supplement is approved, you must sign up for both plans within the same enrollment window.
When switching your coverage, following certain guidelines is essential, and the process can be confusing. Our advisors can walk you through each step based on your personal situation to ensure a smooth transition without gaps in coverage.
Supplement Medical Underwriting: What to Expect
During your Medigap Open Enrollment Period, you're guaranteed acceptance into any Supplement plan. Insurers can't deny you or charge more because of pre-existing health conditions.
After the enrollment window closes, insurance companies may require you to go through medical underwriting. This process involves an examination of your health history, which could result in higher premiums or even a denial of your application, especially if you have ongoing or chronic health conditions. We strongly recommend speaking with one of our licensed advisors before making any changes to your coverage.
Once approved, your Supplement will automatically renew each year, regardless of any health changes.
Frequently Asked Questions
Is it okay to apply for a Supplement while my Medicare Advantage plan is still active?
Yes — it's actually the recommended approach. Staying on your current plan during the application process ensures you remain covered, no matter the outcome.
What if my Supplement application is denied after I've already left my Medicare Advantage plan?
This is why you should never drop your Medicare Advantage plan before your Supplement is approved. A denial could leave you with a gap in coverage and limited options. Apply first, confirm approval, then enroll in Part D – all within the same enrollment window.
Do I need to cancel my Medicare Advantage plan before enrolling in Part D?
No. Enrolling in a standalone Part D plan automatically replaces your Medicare Advantage plan; you don't need to cancel it separately. But if you enroll in Part D before your Supplement is approved, your Medicare Advantage coverage — including drug benefits — will end before your new coverage begins. Always wait for written Supplement approval first.
Thinking about making the switch? We’re here to help.
If you’re considering switching from a Medicare Advantage plan to a Supplement, our knowledgeable advisors can help walk you through each step. Contact us today!