In switching to original medicare, beware of Medigap plan refusals

It's open enrollment season for Medicare Advantage, when people currently enrolled in private managed-care plans can either sign up for a new one or switch to original Medicare through March 31.

But there's a catch: If people want to move to original Medicare and buy a supplemental Medigap insurance plan to cover some out-of-pocket costs, they may not be able to. Medigap insurers can generally refuse coverage to applicants whose medical history or current health problems might make them expensive to cover, a process called medical underwriting.

"We really want people to factor that in," said Kata Kertesz, managing policy attorney at the Center for Medicare Advocacy. "If someone is in a Medicare Advantage plan for several years and then wants to switch to original Medicare, they may find they can't switch and also get a Medigap plan."

There are many reasons people might want to trade their MA plan for traditional Medicare. Although MA managed-care plans are typically cheaper and offer benefits not available in original Medicare, such as coverage for vision and hearing services, they have smaller provider networks than the original program and, sometimes, extensive prior authorization requirements.