| # | County | EPA radon zone |
|---|---|---|
| 1 | Anderson County | 3 |
| 2 | Andrews County | 3 |
| 3 | Angelina County | 3 |
| 4 | Aransas County | 3 |
| 5 | Archer County | 3 |
| 6 | Atascosa County | 3 |
| 7 | Austin County | 3 |
| 8 | Bandera County | 3 |
| 9 | Bastrop County | 3 |
| 10 | Baylor County | 3 |
| 11 | Bee County | 3 |
| 12 | Bell County | 3 |
| 13 | Bexar County | 3 |
| 14 | Blanco County | 3 |
| 15 | Borden County | 3 |
| 16 | Bosque County | 3 |
| 17 | Bowie County | 3 |
| 18 | Brazoria County | 3 |
| 19 | Brazos County | 3 |
| 20 | Briscoe County | 3 |
| 21 | Brooks County | 3 |
| 22 | Brown County | 3 |
| 23 | Burleson County | 3 |
| 24 | Burnet County | 3 |
| 25 | Caldwell County | 3 |
Source: EPA Map of Radon Zones (September 2025). All counties with data are ranked. Estimates carry margins of error.
Citing this page: GIS Map, “Counties with the Highest Radon Potential in Texas”, https://gismap.land/rankings/texas/highest-radon-counties. Figures from EPA Map of Radon Zones (September 2025).
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