The U.S. health insurance industry is highly concentrated, with a single insurer having at least a 50% market share in 13 U.S. states.

This trend has intensified over the last 10 years due to industry consolidation, leaving consumers with limited options for health insurance. Going further, in markets dominated by a few insurers, healthcare costs and spending tend to be higher as insurers are less likely to reimburse hospitals for patient care.

This graphic, via Visual Capitalist's Dorothy Neufeld, shows America’s largest health insurance companies by state, based on data from the American Medical Association.

The Market Concentration of Health Insurers in 2023

Below, we show the top health insurance company in each U.S. state, measured by their share of total enrollments in 2023:

Last year, Blue Cross Blue Shield covered 86% of all enrollments in Alabama, making it the most concentrated health insurance market nationwide.

Ranking in second is Kentucky, where Elevance Health makes up 67% of the market share. Overall, six of the most concentrated states are located in the South. Going further, the region has higher levels of uninsured rates compared to other regions driven by states opposing the expansion of Medicaid.

In comparison, the Northwestern states of Washington and Oregon have the least concentrated health insurance markets, each with one company controlling a 21% share.

Overall, Blue Cross Blue Shield was the top health insurance company in 14 states, followed by Elevance Health in 10 states. While UnitedHealth Group is America’s largest insurer on a national level, it is comparatively less concentrated state-wide, being the top provider in states such as New York and Arizona.

Shifting Business Models

Beyond having significant market concentration across states, many health insurance companies are diversifying into other noninsurance healthcare services.

For instance, Cigna, the top health insurance company in Wyoming, generated roughly 75% of its revenues from noninsurance services in Q3 2023. For Elevance Health, noninsurance business activities made up 25% of revenues, spanning from pharmacy services to primary care.

In many ways, health insurers are becoming increasingly vertically integrated, which has also been shown to raise prices and reduce competition in healthcare systems.

To learn more about this topic from a national perspective, check out this graphic on the largest health insurance companies in America.