Two insurers dominate most Medicare Advantage markets, report finds
The vast majority of Medicare Advantage markets leave patients with only one or two insurance companies to choose from—signaling that, despite the privatized Medicare Part C being more popular than ever, the landscape remains heavily consolidated.
A new report from KFF revealed that UnitedHealthcare and Humana dominate in terms of market share, with 59% of all Medicare Advantage enrollees using their plans. The two companies hold the largest market share in two-thirds of all counties in the U.S., according to 2024 enrollment data.
KFF said that 97% of all counties in the U.S. fall into either the “highly” or “very highly” consolidated categories for Medicare Advantage, with 90% of all patients living in counties where more than 50% of enrollees use one or two companies.
In most of those counties, UnitedHealthcare and Humana were the two dominant providers, together owning a total of 66% of all available plans.
Further, when comparing rural counties to urban ones, the former have higher levels of consolidation overall, KFF concluded. While 18% of all counties are measured as “very highly consolidated,” that number rises to 40% in rural America.
Some of the data presented by KFF shows an overall improvement toward reduced consolidation, albeit a small one.
“In 2024, 90% of eligible Medicare beneficiaries—54.3 million out of 60.5 million—lived in a county where at least 50% of Medicare Advantage enrollees in that county were in plans sponsored by one or two insurers,” the report reads. “This represents a small decrease since 2010, when 96% of eligible beneficiaries—41.4 million out of 43.5 million—lived in a county where at least half of Medicare Advantage enrollees were in plans sponsored by one or two insurers.”
Humana and UnitedHealth dominate the least competitive markets
When zooming in on areas of the country with the fewest options, KFF found that UnitedHealthcare operated the most Medicare Advantage plans in 2024. The company held a 50% share in “very highly concentrated” counties and 41% in “highly concentrated” counties, making it the top insurer in those regions.
Humana came in second, dominating 22% of very highly concentrated areas and offering the most plan options in 26% of highly concentrated counties.
In other areas, Blue Cross Blue Shield affiliates were the largest Medicare Advantage insurer in 11% of all counties, followed by CVS Health with 8% and Elevance Health with 4%.
KFF said it used data from the Centers for Medicare & Medicaid Services (CMS) on Medicare Advantage enrollment, ranging from 2010 to 2024.
The full report is available here.
Chad is an award-winning writer and editor with over 15 years of experience working in media. He has a decade-long professional background in healthcare, working as a writer and in public relations.