Medicare open enrollment may hide a Medigap eligibility gap

People switching from Medicare Advantage to original Medicare can face Medigap denials because insurers commonly use medical underwriting after the initial six-month Medigap window, and the open enrollment period runs through March 31.

Many people are switching from Medicare Advantage back to original Medicare during this enrollment period. Some may expect that they can enroll in Medigap supplemental coverage when needed. Insurers often use medical underwriting after the initial six-month Medigap enrollment window, which can prevent some applicants from enrolling in Medigap. Key points: - After the six-month Medigap enrollment window tied to initial Part B enrollment, insurers in most states may apply medical underwriting and can deny applicants based on health history. - A JAMA study reported that roughly 2.9 million Medicare Advantage enrollees had to find new coverage for 2026 after plans left their markets, increasing the number of people seeking alternative coverage. - Federal guaranteed-issue situations include a trial right, plan exits, relocations, and state-specific rules in Connecticut, Massachusetts, New York, and an annual Maine window. - The State Health Insurance Assistance Program (SHIP) offers free, state-specific counseling and a Medigap comparison tool, as reported by advocacy groups. Summary: Medigap underwriting limits can affect access to supplemental coverage for people leaving Medicare Advantage, which may alter their coverage options. The open enrollment period runs through March 31.