Millions of Americans lose their Medicare Advantage plans each year, or their plan’s network changes and their doctors and hospital systems are no longer covered.

Breakups are on the rise as hospitals and physician groups grow increasingly exasperated with insurance companies blocking medical care through preauthorizations and other red tape. At the same time, some insurers are jettisoning plans, hospital systems, and doctors.

A prime example: UnitedHealthcare (UNH) and Johns Hopkins Medicine ended their network contract in August. That meant most Johns Hopkins facilities and providers became out of network for patients with UnitedHealthcare Medicare Advantage plans.

For Medicare Advantage enrollees caught in the fray, it can be an expensive bad dream. When your long-standing doctor or preferred hospital is no longer covered by your insurance plan, for example, you’re considered out of network.

That means you’re seeing a healthcare provider or receiving services at a medical center that doesn’t have an agreement with your health insurance plan to pick up most, if not all, of the bill. The upshot for you: Pay the steep out-of-pocket costs, or find a new provider.

Last fall, the Centers for Medicare & Medicaid Services (CMS) issued a proposed rule that would revise the process for Medicare Advantage enrollees who experience midyear provider network changes, according to a CMS fact sheet.

When providers and insurers split up, CMS reportedly gives enrollees a “special enrollment period” to change plans or enroll in traditional Medicare midyear. But how that works has been unclear and confusing. That prompted the proposed provision to make it easier.

Now CMS has dropped the proposal, which would have taken effect in 2027.

“We were disappointed that CMS did not finalize the provision to help more MA enrollees impacted by midyear network changes keep their doctor,” Lindsey Copeland, director of federal policy at the Medicare Rights Center, told Yahoo Finance.

“Abruptly losing access to a trusted provider is a difficult experience, especially for people with complex or serious conditions,” she said.

Medicare Advantage is an alternative health insurance program to traditional Medicare for those ages 65 and older. The plans are run by private insurance companies and cover benefits not included in traditional Medicare, such as drug coverage (Part D), eyeglasses, dental care, and fitness classes. Plus, they typically have very low or even no premium costs.

There’s a flip side. Unlike original Medicare, depending on the Advantage plan, you’re limited to a specific network of doctors and other healthcare providers, and those networks are ever-changing.

And that’s what the dismissed provision would have helped people navigate.

Friction between Medicare Advantage plans and the doctors, hospitals, and other providers that serve their members is not unusual, often stemming from the requirement for prior authorization for care, a restriction only rarely required in traditional Medicare.

The two largest Medicare Advantage insurers, UnitedHealthcare and Humana (HUM), offer plans in about 80% of US counties in 2026, down from nearly 90% last year.

So far this year, dozens of hospital systems have jettisoned Advantage plans. According to one analysis, 1 in 10 Medicare Advantage enrollees, or as many as 2.9 million seniors, “face forced disenrollment in 2026.”

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“When a plan is terminated by the insurer, if they offer another plan of the same type in the county, they can crosswalk somebody to that other plan,” Jeannie Fuglesten Biniek, associate director of the program on Medicare policy at KFF, previously told Yahoo Finance. “The key will be to check if your doctors are going to be in the new one you’re being folded into.”

If you do nothing when you receive the notice, you’ll be enrolled in a replacement plan. If the company is exiting a market altogether, you’ll have to sign up for a new Medicare Advantage plan or switch to traditional Medicare for next year.

Kerry Hannon is a Senior Columnist at Yahoo Finance. She is a career and retirement strategist and the author of 14 books, including "Retirement Bites: A Gen X Guide to Securing Your Financial Future," "In Control at 50+: How to Succeed in the New World of Work," and "Never Too Old to Get Rich." Follow her on Bluesky and X.

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