Commercial health insurance markets are continuing to become more concentrated, according to the AMA’s 2025 “Competition in health insurance” report published Dec. 16.
The 24th annual report analyzed insurer market concentration across 384 metropolitan areas and all 50 states and D.C.
10 things to know:
1. Ninety-seven percent of commercial health insurance markets at the metropolitan level were highly concentrated in 2024, up from 95% in 2014.
2. In 47% of metro areas, a single insurer controlled at least half the market. In 91% of metro areas, at least one insurer held a market share of 30% or more.
3. The 10 largest commercial insurers nationally by market share were UnitedHealth Group (16%), Elevance Health (12%), CVS/Aetna (12%), Cigna (9%), Health Care Service Corp. (8%), Kaiser Permanente (6%), Centene (3%), Florida Blue (2%), BCBS Michigan (2%) and Highmark (2%).
4. BCBS companies collectively hold a 43% national commercial market share and are the largest insurer in 43 states and 84% of metro areas.
5. The 10 states with the least competitive commercial markets are Alabama, Kentucky, Hawaii, Michigan, Louisiana, Illinois, Alaska, Vermont, Delaware and West Virginia.
6. Medicare Advantage markets remain highly concentrated (97%), down slightly from 99% in 2017.
7. UnitedHealth Group is the largest MA insurer nationally with a 30% market share, followed by Humana (19%) and CVS/Aetna (12%).
8. UnitedHealth Group held the largest MA market share in 44% of metro areas, followed by Humana at 23%.
9. The 10 states with the least competitive MA markets are Wyoming, Rhode Island, Montana, Nebraska, Utah, West Virginia, Mississippi, Oklahoma and Louisiana, along with Washington D.C.
10. Centene has grown significantly in the ACA exchanges, rising from the 76th largest insurer in 2014 among all markets to the largest exchange insurer in 2024 with a 20% market share.
