It’s open enrollment season for Medicare Advantage, when people enrolled in private managed-care plans can 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 might not be able to. Medigap insurers can 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 for 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 Medicare Advantage plan for traditional Medicare. Though MA managed-care plans typically are 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.Also, as Medicare Advantage plan profits have sagged in recent years, a growing number of plans are pulling out of areas they used to serve, leaving members with fewer options. This year, an estimated one in 10 MA plan members will be forced out of their plans for this reason, according to a study published in JAMA in February.“We saw some Medicare Advantage plans that just left the market completely and stopped issuing plans,” said Emily Whicheloe, education director for the Medicare Rights Center.For those considering a switch to original Medicare, getting a Medigap plan can be tricky. Federal law provides a onetime, six-month opportunity for people 65 or older and newly covered by Medicare Part B to sign up for any Medigap plan without underwriting.After that initial sign-up period ends, there are fewer coverage guarantees. But some do exist.Here are a few key circumstances and time frames in which people are guaranteed a Medigap plan without having to undergo underwriting:People who sign up for a Medicare Advantage plan when they are first eligible for Medicare Part A at 65 can switch to original Medicare within the first year and buy a Medigap plan, too. This is sometimes called the “trial right.”If a Medicare Advantage plan leaves Medicare or stops providing services in an area, affected enrollees can switch to original Medicare and buy a Medigap plan either 60 days before or up to 63 days after their MA coverage ends. During this special enrollment period, they can’t be turned down or charged more based on their health.If people move out of the service area and no longer have access to their Medicare Advantage plan providers, they can switch to original Medicare and apply for a Medigap policy either 60 days before or up to 63 days after their MA coverage ends. That typically happens when someone notifies the plan of their permanent move or the plan discovers it, said Bonnie Burns, a consultant for California Health Advocates who specializes in Medicare and Medigap coverage.Patient advocates say it’s often useful to work with a counselor at the State Health Insurance Assistance Program for free, unbiased help figuring out Medigap coverage options. SHIP counselors can help identify ways to qualify, without underwriting, for Medigap coverage at the federal and state levels.People who don’t qualify for a guaranteed right to a Medigap plan without underwriting can still be approved for coverage. But premiums might be higher, and plans can impose a waiting period of up to six months for coverage of preexisting medical conditions in certain circumstances.In recent years, some Medigap insurers have spent a growing percentage of premiums on medical claims, putting pressure on profits, Burns said. “Medigap insurers’ underwriting has tightened up considerably recently,” she said.The list of health conditions Medigap insurers might deny coverage for is long, including Alzheimer’s disease, asthma, cancer, congestive heart disease, diabetes with complications, end-stage renal disease, high blood pressure and stroke, according to a KFF review of leading insurers’ applications.When people apply for a Medigap plan that will be medically underwritten, they typically will be asked to fill out a health questionnaire, said Nick Ortner, a principal and consulting actuary at the firm Milliman who is a Society of Actuaries fellow. Increasingly, insurers are requesting that people agree to a prescription-drug background check, Ortner said.“Oftentimes, that prescription drug history may be the primary driver of a decision as it relates to underwriting,” Ortner said, rather than a physical exam or medical records review.Insurers don’t all have the same underwriting rules, though. Again, a SHIP counselor might be useful for pointing people to companies that accept applicants with a particular medical diagnosis or have different waiting periods or coverage exclusions.“They have access to a Medigap comparison tool in addition to what is existing on medicare.gov that can give you a very good estimate of what you may pay for those Medigap plans,” said Ryan Ramsey of the National Council on Aging. Ryan Ramsey of the National Council on Aging.Provided KFF Health News is a national newsroom that produces in-depth journalism on health issues. ...read more read less