" " Although a Medicare Advantage plan can be cheaper, there are times when it pays to take a Medigap policy instead. AdvertisementAdvertisementBecause so many potential health care budget-busters remain after Medicare pays its share, many retirees opt to do one of two things: purchase Medicare Part D, which covers prescription drugs, along with a Medicare Supplement plan, better known as Medigap. Or they ditch all Medicare plans (Parts A, B and D) and purchase a Medicare Advantage plan. Medicare Advantage plans, also offered by private insurers, provide all of the same benefits as Medicare Part A and Medicare Part B. In 2018, 22 million people, or one-third of all Medicare beneficiaries, were receiving care through Medicare Advantage plans,.