1. You must have Medicare Part A and Part B before enrolling in a Medigap (or Medicare Supplement) plan. 2. If you have a Medicare Advantage Plan and want to move to a Medigap Plan, make sure to leave your Advantage plan before your Medigap coverage begins. 3. A Medigap Policy only covers one person. 4. In addition to paying your Part B premium every month, you will also pay a monthly premium for your Medigap Plan. 5. As long as you pay your premium, an insurance company cannot cancel your policy no matter what health problems you may have. It is guaranteed renewable. See ManhattanLife's Medicare Supplement for plan information.