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Mapped: The Top Health Insurance Companies by State
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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 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:
| State | Top Health Insurer | Market Share in 2023 |
|---|---|---|
| Alabama | Blue Cross Blue Shield | 86% |
| Kentucky | Elevance Health | 67% |
| Louisiana | Blue Cross Blue Shield | 66% |
| Hawaii | Hawaii Medical Service Association | 63% |
| Illinois | Health Care Service Corporation | 63% |
| South Carolina | Blue Cross Blue Shield | 59% |
| Oklahoma | Health Care Service Corporation | 57% |
| Vermont | Blue Cross Blue Shield | 57% |
| Delaware | Highmark | 56% |
| Indiana | Elevance Health | 56% |
| West Virginia | Highmark | 52% |
| Mississippi | Blue Cross Blue Shield | 50% |
| Montana | Health Care Service Corporation | 50% |
| New Hampshire | Elevance Health | 48% |
| North Carolina | Blue Cross Blue Shield | 48% |
| North Dakota | Blue Cross Blue Shield | 48% |
| Iowa | Wellmark | 47% |
| Alaska | Premera | 46% |
| Utah | Intermountain | 46% |
| Arkansas | Blue Cross Blue Shield | 45% |
| Kansas | Blue Cross Blue Shield | 45% |
| Nebraska | Blue Cross Blue Shield | 45% |
| Texas | Health Care Service Corporation | 44% |
| Maine | Elevance Health | 43% |
| Maryland | CareFirst | 43% |
| Massachusetts | CareFirst | 43% |
| Virginia | Elevance Health | 43% |
| Idaho | Blue Cross of Idaho | 42% |
| Rhode Island | Blue Cross Blue Shield | 42% |
| Tennessee | Blue Cross Blue Shield | 42% |
| Wyoming | Cigna | 40% |
| New Jersey | Horizon | 39% |
| Minnesota | Blue Cross Blue Shield | 38% |
| New Mexico | Health Care Service Corporation | 38% |
| California | Kaiser | 37% |
| Connecticut | Elevance Health | 37% |
| Florida | Blue Cross Blue Shield | 36% |
| Nevada | UnitedHealth Group | 36% |
| Michigan | Blue Cross Blue Shield | 35% |
| Georgia | Elevance Health | 33% |
| South Dakota | Avera Health | 33% |
| Ohio | Elevance Health | 31% |
| Pennsylvania | Highmark | 31% |
| Missouri | Elevance Health | 29% |
| Arizona | UnitedHealth Group | 28% |
| Wisconsin | UnitedHealth Group | 27% |
| New York | UnitedHealth Group | 26% |
| Colorado | Elevance Health | 24% |
| Oregon | Cambia | 21% |
| Washington | Kaiser | 21% |
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.
Learn More on the Voronoi App 
To learn more about this topic from a national perspective, check out this graphic on the largest health insurance companies in America.
