To find out where in the US health insurance coverage is highest and lowest, SmartAsset ranked 810 counties based on the percentage of people aged under 65 who were insured in 2024.

Texas dominates the list of US counties with the lowest rates of health insurance coverage, accounting for 19 of the study's top 20. Hidalgo County, Texas (32.05 percent), has the highest share of uninsured residents nationwide, followed by Cameron County, Texas (30.08 percent), and Webb County, Texas (29.69 percent).

The only non-Texan county in the top 20 is Whitfield County, Georgia, where 23.43 percent of people don't have health insurance.

Coverage is highest in Norfolk County, Massachusetts, with just 2.39 percent of residents going without health insurance. In fact, more than 96 percent of Massachusettsans are insured overall.

Via SmartAsset.

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