Switching from a Medicare Advantage (MA) plan to a Medigap (Medicare Supplement Insurance) plan is possible, but the transition requires navigating precise timing windows and regulatory requirements. The process involves three steps: first, disenroll from your MA plan, which automatically returns you to Original Medicare (Part A and Part B). Then, you can apply for a Medigap policy and enroll in a separate, standalone Part D prescription drug plan. Success depends heavily on specific enrollment periods and your current health status.
Returning to Original Medicare
Medigap policies are designed by private insurance companies to work exclusively with Original Medicare (Part A and Part B). Since you cannot have both a Medicare Advantage plan and a Medigap policy simultaneously, the first mandatory step is canceling the MA plan and reverting to Original Medicare. You must be actively enrolled in both Part A and Part B before applying for a Medigap policy.
You can disenroll from the Medicare Advantage plan during an approved enrollment period using several methods. You can contact the plan provider directly to request a disenrollment form or call 1-800-MEDICARE to process the cancellation over the phone. A simpler method is to enroll in a standalone Medicare Part D plan or a Medigap policy during an eligible election period, which automatically ends your Medicare Advantage enrollment.
Critical Enrollment Periods for Switching
The ability to switch coverage depends entirely on making the move during specific, government-mandated timeframes. The Annual Enrollment Period (AEP), running from October 15th to December 7th, allows you to drop an MA plan and return to Original Medicare. The change takes effect on January 1st of the following year, making this the most common time for beneficiaries to make a planned change.
A second opportunity exists during the Medicare Advantage Open Enrollment Period (MA OEP), which runs annually from January 1st to March 31st. This period allows individuals already enrolled in an MA plan to switch back to Original Medicare, with coverage starting the first of the month after the request is received. Outside of these periods, certain life events may trigger a Special Enrollment Period (SEP), such as moving out of the plan’s service area or the plan ceasing to offer coverage.
Certain individuals are granted “Trial Rights,” which provide Guaranteed Issue protection outside of standard enrollment windows. These rights apply if you joined an MA plan when you were first eligible for Medicare at age 65 and wish to switch back within the first 12 months. A second trial right exists if you dropped a Medigap policy to enroll in an MA plan for the first time and want to switch back within 12 months. These rights allow a seamless, no-underwriting switch back to Medigap coverage within a specific timeframe.
Navigating Medical Underwriting Requirements
The most significant barrier when switching from an MA plan to Medigap is the requirement for medical underwriting. Underwriting is the process where insurance companies evaluate your health history and pre-existing conditions to determine if they will accept your application and what premium they will charge. If you apply for a Medigap policy outside of your initial six-month Medigap Open Enrollment Period or a specific guaranteed issue window, the insurer can deny coverage or charge higher rates based on your health.
Securing a Guaranteed Issue Right (GIR) is frequently the only viable path for individuals with pre-existing conditions to switch successfully. Federal law mandates that Medigap insurers must accept an application without medical underwriting in certain scenarios. These federally-mandated GIRs apply when an individual involuntarily loses existing coverage, such as when an MA plan leaves the service area or stops providing coverage.
Other guaranteed issue scenarios include moving out of the MA plan’s service area or utilizing the trial rights periods. When a GIR applies, the Medigap insurer cannot deny the policy or discriminate in pricing based on health status. The application window is typically limited to a 63-day period starting when the prior coverage ends, requiring prompt action to secure the protection.
Securing Prescription Drug Coverage
A key detail in the transition is that Medigap policies do not include prescription drug coverage (Part D). Unlike most Medicare Advantage plans, which bundle Part D coverage, Medigap policies only supplement the out-of-pocket costs of Original Medicare. Therefore, once you return to Original Medicare, you must enroll in a separate, standalone Part D prescription drug plan to maintain drug coverage.
Failing to enroll in a Part D plan or another form of creditable prescription drug coverage can result in a permanent late enrollment penalty. This penalty is incurred if you go without creditable coverage for a continuous period of 63 days or more after leaving the MA plan. The penalty is calculated by multiplying 1% of the national base beneficiary premium by the number of full, uncovered months without coverage, and this amount is permanently added to your monthly Part D premium.