Health insurance companies that are the biggest players in privatized Medicare Advantage coverage are pulling back a little bit after years expanding their geographic footprints even while they offer new benefits. With more than half of the nation's eligible seniors enrolled in Medicare Advantage plans, competition has been fierce offering seniors more lucrative benefits and more choices. But this fall, seniors will find during open enrollment that many of these plans including Aetna, Cigna, Humana and some regional insurers and startups are no longer offering Medicare Advantage in certain states and counties for the 2025 health benefit year.