The health insurance market was highly concentrated in 42 of the 50 states in 2019 and 2020 – the continuation of a trend identified in 2010 that has persisted ever since, according to a new report by the U.S. Government Accountability Office.

The GAO considers a market concentrated if three or fewer insurers in a state have 80 percent of that market.  Using Centers for Medicare & Medicaid Services health insurance enrollment data, the GAO looked at three distinct aspects of markets – individual policies, small group policies, and large group coverage – and found that

  • Each of the three markets in 2020 was concentrated in at least 42 states (including the District of Columbia).
  • The individual and small group markets generally became more concentrated in recent years. The median market share of the top three issuers in each market increased by 12 and 10 percentage points, respectively, from 2011 through 2020. With these increases, their median market share was at least 97 percent in both markets in 2020.

Learn more about the study’s origins in the Affordable Care Act and why its findings matter in the GAO report “Private Health Insurance:   Markets Remained Concentrated through 2020, with Increases in the Individual and Small Group Markets.”