If you're enrolled in a Medicare Advantage plan, 2026 brings an unusually high level of disruption to the market. A study from the Johns Hopkins Bloomberg School of Public Health found that roughly 1 in 10 Medicare Advantage enrollees — approximately 1.6 million people nationwide — are being forced out of their current plans this year, not by their own choice, but because insurers are withdrawing from counties, shrinking service areas, or exiting the Medicare Advantage market altogether. This is one of the largest waves of involuntary disenrollment the program has seen in recent years, and it has real consequences for people who built their care routines around a specific network of doctors, hospitals, and drug formularies.
The driving force behind these exits is financial pressure on insurers. Medicare Advantage plans are paid a fixed rate by the federal government to cover each enrollee, and in recent years, many insurers have reported that their actual costs — particularly for hospital stays, post-acute care, and specialty drugs — have exceeded those payments. Major insurers including Humana and UnitedHealthcare have publicly announced reductions in their Medicare Advantage footprints for 2026, pulling out of counties where margins were too thin. Smaller regional plans have done the same. The result is a patchwork of coverage gaps, particularly in rural and suburban counties where plan competition was already limited.
If your plan is one of those exiting, you should have received a notice from your insurer — typically sent by late September or early October of the prior year — informing you that your coverage will end on December 31. This notice triggers a Special Enrollment Period (SEP) that allows you to enroll in a new Medicare Advantage plan or switch back to Original Medicare (Parts A and B) without waiting for the standard Annual Enrollment Period (AEP), which runs October 15 through December 7. Your SEP window generally runs from the date you receive your notice through February 28 of the following year, though acting before January 1 is strongly recommended to ensure continuous coverage. If you miss this window without enrolling elsewhere, you do not simply lose Medicare — you revert to Original Medicare — but you could face a period without drug coverage if you don't also enroll in a standalone Part D plan.
One of the most consequential decisions forced disenrollees face is whether to stay in the Medicare Advantage system or return to Original Medicare paired with a Medigap supplement policy. Original Medicare covers roughly 80% of approved costs, leaving you responsible for the remaining 20% with no out-of-pocket cap. A Medigap policy fills those gaps, but here's the critical catch: in most states, insurers can use medical underwriting to deny you a Medigap policy or charge you higher premiums based on your health history if you're not in a guaranteed issue window. Federal law provides a guaranteed issue right when you involuntarily lose Medicare Advantage coverage — meaning insurers must sell you certain Medigap plans without medical underwriting — but this right is time-sensitive, typically lasting 63 days from the date your plan coverage ends. If you're in California, Idaho, Illinois, Kentucky, Louisiana, Maine, Maryland, Missouri, Nevada, New Jersey, New York, Oklahoma, or Oregon, your state provides additional Medigap protections, including birthday rule windows that allow annual plan switches without underwriting.
For those who want to stay in Medicare Advantage, the practical task is comparing replacement plans carefully. In 2026, plan benefits, premiums, drug formularies, and provider networks vary significantly even within the same county. A plan that covers your cardiologist may not cover your orthopedic surgeon. A plan with a $0 premium may carry a $7,550 or higher in-network out-of-pocket maximum. Use Medicare's Plan Finder tool at Medicare.gov to enter your specific prescriptions and preferred doctors before selecting a replacement. Your State Health Insurance Assistance Program (SHIP) — a free, federally funded counseling service available in every state — can walk you through this comparison at no cost. To find your local SHIP counselor, call 1-800-MEDICARE or visit shiphelp.org.
The broader policy question raised by this disruption is whether Medicare Advantage's structure adequately protects enrollees from market volatility. Unlike Original Medicare, which is a federal entitlement with no geographic gaps, Medicare Advantage is delivered through private insurers who can and do exit markets when profitability declines. Researchers at Johns Hopkins and other health policy institutions have noted that forced disenrollment disproportionately affects older, sicker enrollees who have built long-term relationships with specific providers — and who may face the greatest difficulty navigating a plan switch mid-care. Congress and CMS have discussed strengthening notice requirements and SEP protections, but as of April 2026, no new federal rules have been finalized specifically addressing the scale of this year's exits.
If you received a disenrollment notice or are unsure whether your plan is continuing in your area, the most direct step is to call your plan directly and ask for written confirmation of your coverage status through December 31, 2026. Then use Medicare.gov's Plan Finder to see what alternatives exist in your ZIP code. Don't wait until the last week of your SEP — processing times for new enrollments can take two to four weeks, and you want your new coverage confirmed before your old plan ends.