Medigap Underwriting Risks Create Barriers for Retirees Attempting to Switch from Medicare Advantage Plans

Beware of medical underwriting when switching from Medicare Advantage to original Medicare. Learn how Medigap insurers use health history to deny coverage.

By: AXL Media

Published: Mar 16, 2026, 7:27 AM EDT

Source: Information for this report was sourced from KFF Health News

The Hidden Complexity of Medicare Open Enrollment

The Medicare Advantage open enrollment season, running through March 31, presents an opportunity for seniors to reassess their private managed-care coverage. However, a critical pitfall awaits those intending to revert to original Medicare and pair it with a Medigap supplemental policy. Unlike the initial enrollment period, most returning applicants are subject to medical underwriting, a process where insurers evaluate health history to determine eligibility and pricing. According to Kata Kertesz, managing policy attorney at the Center for Medicare Advocacy, many individuals who have utilized Medicare Advantage for several years discover too late that their current health status makes them uninsurable in the supplemental market.

Structural Shifts and Plan Withdrawals

A primary motivation for exiting Medicare Advantage is the recent volatility in the private insurance market. As profit margins have contracted, a significant number of providers are withdrawing from specific geographic regions, a trend affecting approximately 10% of plan members this year according to research published in JAMA. While Medicare Advantage often appeals to consumers through lower premiums and added benefits like vision and hearing, the trade-off includes restricted provider networks and rigorous prior authorization mandates. When a plan exits a market, it triggers a federal protection allowing affected members to switch to original Medicare with guaranteed Medigap access, but this window is strictly limited to approximately 60 days.

Navigating Federal and State Protections

While federal law typically only guarantees a one-time, six-month underwriting-free window upon turning 65, certain "trial rights" and state-specific regulations offer narrow paths for others. New York, Connecticut, and Massachusetts provide year-round enrollment without underwriting, while Maine offers a specific annual window for basic coverage. Additionally, those who joined a Medicare Advantage plan when first eligible at 65 have a one-year trial period to revert to original Medicare with guaranteed Medigap rights. Outside of these specific scenarios or instances of relocation, most applicants must navigate a gauntlet of health questionnaires and background checks.