Key Takeaways

• Switching from Medigap to Medicare Advantage may seem cost-effective, but it comes with limitations that could affect your access to care and overall expenses.

• You may not be able to switch back to Medigap later without undergoing medical underwriting, potentially leaving you with fewer options if your health changes.

Why Many Consider Switching

Medigap, or Medicare Supplement Insurance, is designed to fill the gaps in Original Medicare by covering out-of-pocket expenses like deductibles, coinsurance, and copayments. However, in 2025, many people are looking to switch to Medicare Advantage (Part C) plans due to lower upfront costs, bundled benefits, and extras like dental or vision coverage.

But before making that change, you need to understand what you’re potentially giving up—and whether the trade-offs are really in your favor long-term.

What You Lose When You Leave Medigap

When you replace your Medigap policy with a Medicare Advantage plan, you exit Original Medicare and enroll in a private health plan that follows Medicare rules. Here’s what that means for you:

Limited Provider Networks

• With Medigap, you can see any doctor who accepts Medicare nationwide.

• Medicare Advantage plans typically have restricted networks of doctors and hospitals.

• Going out of network may result in higher costs or even no coverage, especially for specialized or out-of-state care.

Referrals and Prior Authorizations

• Most Medicare Advantage plans require referrals to see specialists.

• Prior authorization is often needed for services like hospital stays, MRIs, or surgeries.

• These administrative steps can delay care or even result in denied claims.

Loss of Predictability in Costs

• Medigap plans offer relatively predictable out-of-pocket expenses.

• Medicare Advantage plans have varying copayments, coinsurance, and out-of-pocket maximums—up to $9,350 for in-network services in 2025.

• Unexpected health events could make Advantage plans more expensive in the long run.

Rejoining Medigap Isn’t Guaranteed

One of the most important facts to know is this: if you give up your Medigap plan, you might not be able to get it back later.

The One-Time Guarantee

• When you first enroll in Medicare Part B (usually at age 65), you have a six-month Medigap open enrollment period.

• During this time, you can buy any Medigap policy available in your state without being denied or charged more based on your health.

• After this window, you may have to go through medical underwriting.

Limited Guaranteed Issue Rights

• Federal rules give you certain situations—called “guaranteed issue rights”—where you can get Medigap without underwriting.

• These include losing other coverage, moving out of a plan’s service area, or your Medicare Advantage plan leaving Medicare.

• Simply choosing to leave a Medicare Advantage plan does not give you guaranteed issue rights in most cases.

Your Health Could Block Your Return

• If you develop a chronic condition or face a major health event after switching to Medicare Advantage, you may be denied Medigap coverage if you try to return later.

• Even if accepted, you may face higher premiums due to your health status.

Coverage May Not Be as Robust

People often switch to Medicare Advantage for the promise of extra benefits. But those extras sometimes come with hidden trade-offs.

Supplemental Benefits Are Not Standard

• Dental, vision, and hearing benefits vary widely between plans.

• These extras are not guaranteed from year to year.

• Networks for supplemental services may be even more limited than medical provider networks.

Prescription Drug Coverage May Differ

• Medicare Advantage plans often include drug coverage (Part D).

• Formularies (the list of covered drugs) vary by plan and may change annually.

• Some drugs may require step therapy or prior authorization.

Annual Plan Changes Can Be Disruptive

Medicare Advantage plans reset annually. Benefits, costs, networks, and even plan availability may change.

• Each year, between October 15 and December 7, you can switch or leave a Medicare Advantage plan during Open Enrollment.

• But if your plan drops your doctor or increases costs, you may not have the ability to return to your original Medigap plan without underwriting.

This yearly uncertainty can be especially difficult for those with ongoing medical needs.

You Might Have Fewer Choices Than You Think

While Medicare Advantage plans are heavily advertised and widely available, they may not offer broad choice in every region.

• Rural areas may have fewer plan options or narrower provider networks.

• If you travel often or spend winters in a different state, coverage limitations could follow you.

Medigap, in contrast, provides the freedom to receive care anywhere in the U.S. that accepts Medicare.

Emergency Coverage While Traveling

If you plan to travel domestically or internationally, understand how each type of coverage handles emergencies.

• Medigap plans C, D, F, G, M, and N cover foreign travel emergencies up to plan limits.

• Medicare Advantage plans may have restrictions on out-of-area emergency care or higher cost-sharing.

Consider the Long-Term Horizon

What feels right now may not serve you well years down the road.

• Medicare Advantage plans may work well while you’re healthy.

• But if your health changes, your access to care could become more limited.

• Reapplying for Medigap later can be costly—or impossible.

Think Through the Timeline Before You Switch

Before leaving Medigap, it’s essential to line up the timing, understand the enrollment rules, and plan for the long-term.

Use These Key Periods Wisely

• Medigap Open Enrollment: Within 6 months of enrolling in Medicare Part B.

• Medicare Advantage Open Enrollment: January 1 to March 31 — for switching between Advantage plans or returning to Original Medicare.

• Annual Enrollment Period (AEP): October 15 to December 7 — allows you to join, switch, or drop a Medicare Advantage plan.

If you want to test out Medicare Advantage but keep Medigap as a backup, understand your state’s rules. Some states offer a “trial right” to return to Medigap within 12 months, but this is not available nationwide.

Get Help Before You Decide

Choosing between Medigap and Medicare Advantage is not just a financial decision—it’s a healthcare access decision. Your needs, preferences, and future plans all matter.

Speak with a licensed agent listed on this website who can help you:

• Understand your eligibility and enrollment rights.

• Compare options without being steered toward a specific plan.

• Navigate potential future limitations.

Think Carefully Before Leaving Your Medigap Safety Net

Switching from Medigap to Medicare Advantage can seem appealing in the short term, but the long-term impact on your access to care, cost stability, and future flexibility could be substantial. Before making the leap, review your current health status, assess possible future needs, and speak with a licensed agent listed on this website for advice tailored to your situation.