Medicare Advantage Open Enrollment Starts in 77 Days. After 2.6 Million Seniors Were Dropped in 2026, Here Is What to Check.

Medicare’s Annual Enrollment Period opens October 15 - 77 days from today. For the roughly 35 million Americans on Medicare Advantage plans, it is the one annual window to switch plans, return to Original Medicare, or change prescription drug coverage without restriction. After insurers dropped 2.6 million seniors from their Advantage plans in 2026, this year’s enrollment period carries more weight than usual.

The 2026 exits were driven by insurers pulling out of counties where costs had outpaced premiums, leaving seniors in rural and mid-sized markets with plans being discontinued. Those seniors were automatically enrolled in alternative coverage - but not necessarily in coverage that matched their previous plan’s network, formulary, or premium structure.

What Is Likely to Change for 2027

Insurer participation in Medicare Advantage has been adjusting each year as companies respond to CMS payment rates and risk adjustment changes. For 2027, some insurers that exited markets in 2026 may not return. Others may enter. The coverage available in your county on October 15 may look significantly different from what was available when you last chose a plan.

Premiums, deductibles, drug formularies, and provider networks can all change year to year even within the same plan. A plan you are currently enrolled in may have cut coverage for medications you take, narrowed its specialist network, or raised its out-of-pocket maximum for 2027. CMS requires plans to notify enrollees of material changes - but those notices arrive in October alongside enrollment materials, not before.

The Deadline and What Happens If You Do Nothing

The Annual Enrollment Period runs October 15 through December 7, 2026. Coverage selected during AEP takes effect January 1, 2027. If you do not actively choose a plan, you remain enrolled in your current plan under whatever terms it offers in 2027 - which may include changed premiums, dropped drugs, or a narrowed network. Doing nothing is also a choice, but it is an uninformed one until the plan’s 2027 materials arrive.

For seniors who were displaced in 2026 and are currently in auto-enrolled coverage, this AEP is particularly important. The plan they were placed in may not be the best match for their prescriptions, providers, or budget.

What to Do Before October

Medicare.gov’s Plan Finder tool will be updated with 2027 plan information starting October 1 - two weeks before enrollment opens. The State Health Insurance Assistance Program (SHIP) in your state provides free, one-on-one counseling. The national SHIP hotline is 1-800-633-4227. Call 1-800-MEDICARE for enrollment questions.

References: Study Reveals Medicare Advantage Dropping Members | 25 Health Systems Have Dropped Medicare Advantage in 2026: Here’s What Enrollees Should Do Now | Is Medicare Part D Ending Subsidy Program?