The American Medical Association (AMA) has released its 2024 edition of "Competition in Health Insurance: A Comprehensive Study of US Markets," which provides an in-depth analysis of health insurance market concentration across the United States. The study examined 382 metropolitan statistical areas (MSAs), all 50 states, and the District of Columbia, focusing on commercial and Medicare Advantage (MA) market shares for the two largest health insurers in each region.
According to federal merger guidelines issued in December 2023, markets that exceed a certain regulatory threshold are considered "highly concentrated." The study found that the majority of health insurance markets have remained highly concentrated over the past decade. In both 2014 and 2023, 95% of commercial markets were classified as highly concentrated. Nearly half (49%) of these markets became even more consolidated by 2023.
"For too many Americans living in highly concentrated health insurance markets, choosing medical coverage feels like having no choice at all," stated AMA President Bruce A. Scott, M.D. He urged regulators, policymakers, lawmakers, and others to engage in discussions aimed at reversing this trend and fostering a more competitive marketplace for patients.
The report highlights several key findings:
- Under current federal guidelines, 95% of MSA-level markets were highly concentrated in both 2014 and 2023.
- In 89% of MSAs, at least one insurer held a commercial market share of 30% or greater. In nearly half (47%) of MSAs, one insurer's share was at least 50%.
- A Blue Cross Blue Shield (BCBS) insurer had the largest state-level market share in 41 states and dominated MSA-level market shares in 83% of MSAs.
- Elevance Health led the MSA-level market share in 21% of MSAs.
- Nationally, UnitedHealth Group held the largest commercial health insurance market share while Centene led in exchange market shares.
- The ten states with the least competitive commercial health insurance markets included Alabama, Kentucky, Michigan, Louisiana, Hawaii, Illinois, Alaska, Delaware, Vermont, and South Carolina.
Medicare Advantage markets also displayed high levels of concentration with little change over time. By 2023, almost all MA markets were highly concentrated with UnitedHealth Group maintaining a national-level share increase from 25% in 2017 to 29%.
The AMA study serves as a resource for identifying potential competitive harms caused by mergers and acquisitions within health insurance markets. It continues to support antitrust advocacy efforts aimed at protecting consumers and healthcare providers from anti-competitive practices.
Additional content from this updated study is available on the AMA’s Competition in Health Care Research website.
