Radon levels in Texas: Low
The model predicts a population-weighted basement average of 1.5 pCi/L (model estimate) across Texas's 253 counties - about 16% below the US average of 1.8 pCi/L. Above-ground floors average 0.8 pCi/L.
Predicted (model estimate). The pCi/L figures on this page are long-term area averages from a peer-reviewed national model built on millions of real radon tests (2001-2021). They describe the typical home in this area - not your home, which can be several times higher or lower. The EPA radon zone is a separate, 1993 county-level classification. How the numbers work.
0 / 254
EPA Zone 1 counties (0%)
39 / 215
Zone 2 / Zone 3 counties
0
counties predicted ≥ 4 pCi/L
0%
of ZIP codes predicted ≥ 4 pCi/L
Test Texas once anyway - radon varies house to house
The predicted basement average here is 1.5 pCi/L, below the EPA's 2 pCi/L "consider fixing" threshold. That's good news for the area - but the EPA still recommends every home be tested, because foundation cracks, soil pockets and ventilation make one house very different from its neighbor. One inexpensive kit settles it.
Monitor link goes to the Airthings store - use code RADONGRADE-10OFF at checkout for 10% off any Airthings monitor.
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What the data says about radon in Texas
On the EPA's 1993 radon zone map, 0 of Texas's 254 counties are EPA Zone 1 (0%), 39 are Zone 2 and 215 are Zone 3. Most counties fall in Zone 3, the EPA's lowest-potential class (predicted screening average under 2 pCi/L). That classification has not been revised since 1993; it describes counties, not homes, and elevated readings turn up in Zone 3 counties every year.
Texas models out at 1.5 pCi/L predicted basement average (low; 16% below the US average of 1.8). Of the 253 counties with predictions, 0 are predicted at or above 4 pCi/L, 61 in the 2-4 band and 192 below 2. The highest predicted county is Hemphill County at 2.5 pCi/L; the lowest is Nueces County at 1.2 - a 1.4 pCi/L spread that means a statewide average tells you little about any one county.
At ZIP-code resolution, 0% of Texas ZIPs are predicted at 4 pCi/L or higher in the basement and 11.7% at 2 or higher - below the national shares of 4.2% and 48.7%. No ZIP in the state is predicted above 4 on average - but averages hide individual homes, which is why the EPA still asks everyone to test.
Texas counties by predicted radon
Sorted highest to lowest predicted basement average (model estimate). 254 counties.
| County | Predicted basement | Upstairs | Grade | EPA zone | ZIPs |
|---|---|---|---|---|---|
| Hemphill County | 2.5 pCi/L | 1.4 | Moderate | EPA Zone 2 | 1 |
| Lipscomb County | 2.5 pCi/L | 1.3 | Moderate | EPA Zone 2 | 4 |
| Moore County | 2.5 pCi/L | 1.4 | Moderate | EPA Zone 2 | 1 |
| Ochiltree County | 2.5 pCi/L | 1.4 | Moderate | EPA Zone 2 | 1 |
| Gray County | 2.4 pCi/L | 1.3 | Moderate | EPA Zone 2 | 2 |
| Sherman County | 2.4 pCi/L | 1.4 | Moderate | EPA Zone 2 | 2 |
| Roberts County | 2.4 pCi/L | 1.3 | Moderate | EPA Zone 2 | 1 |
| Dallam County | 2.4 pCi/L | 1.1 | Moderate | EPA Zone 2 | 2 |
| Carson County | 2.4 pCi/L | 1.3 | Moderate | EPA Zone 2 | 4 |
| Glasscock County | 2.4 pCi/L | 1.1 | Moderate | EPA Zone 3 | 1 |
| Hansford County | 2.4 pCi/L | 1.4 | Moderate | EPA Zone 2 | 2 |
| Armstrong County | 2.4 pCi/L | 1.4 | Moderate | EPA Zone 2 | 2 |
| Donley County | 2.4 pCi/L | 1.2 | Moderate | EPA Zone 2 | 3 |
| Deaf Smith County | 2.4 pCi/L | 1.3 | Moderate | EPA Zone 2 | 2 |
| Parmer County | 2.3 pCi/L | 1.2 | Moderate | EPA Zone 2 | 3 |
| Hartley County | 2.3 pCi/L | 1.2 | Moderate | EPA Zone 2 | 2 |
| Randall County | 2.3 pCi/L | 1.4 | Moderate | EPA Zone 2 | 7 |
| Castro County | 2.3 pCi/L | 1.1 | Moderate | EPA Zone 2 | 4 |
| Oldham County | 2.3 pCi/L | 1.4 | Moderate | EPA Zone 2 | 2 |
| Hutchinson County | 2.3 pCi/L | 1.3 | Moderate | EPA Zone 2 | 4 |
| Brewster County | 2.3 pCi/L | 1.2 | Moderate | EPA Zone 2 | 4 |
| Crosby County | 2.3 pCi/L | 1.1 | Moderate | EPA Zone 2 | 3 |
| Floyd County | 2.2 pCi/L | 1.1 | Moderate | EPA Zone 2 | 2 |
| Hale County | 2.2 pCi/L | 1.2 | Moderate | EPA Zone 2 | 4 |
| Mason County | 2.2 pCi/L | 0.9 | Moderate | EPA Zone 2 | 3 |
| Presidio County | 2.2 pCi/L | 1.3 | Moderate | EPA Zone 2 | 1 |
| Lynn County | 2.2 pCi/L | 1.0 | Moderate | EPA Zone 2 | 2 |
| Swisher County | 2.2 pCi/L | 1.1 | Moderate | EPA Zone 2 | 2 |
| Briscoe County | 2.2 pCi/L | 1.2 | Moderate | EPA Zone 3 | 2 |
| Sutton County | 2.2 pCi/L | 0.9 | Moderate | EPA Zone 3 | 1 |
| Wheeler County | 2.2 pCi/L | 1.0 | Moderate | EPA Zone 3 | 4 |
| Dickens County | 2.2 pCi/L | 1.1 | Moderate | EPA Zone 3 | 4 |
| Lamb County | 2.2 pCi/L | 1.1 | Moderate | EPA Zone 2 | 6 |
| Borden County | 2.2 pCi/L | 1.1 | Moderate | EPA Zone 3 | 2 |
| Garza County | 2.2 pCi/L | 1.2 | Moderate | EPA Zone 2 | 2 |
| Bailey County | 2.1 pCi/L | 1.0 | Moderate | EPA Zone 2 | 4 |
| Mills County | 2.1 pCi/L | 0.9 | Moderate | EPA Zone 3 | 3 |
| Mitchell County | 2.1 pCi/L | 1.0 | Moderate | EPA Zone 3 | 3 |
| Stephens County | 2.1 pCi/L | 1.1 | Moderate | EPA Zone 3 | 2 |
| Callahan County | 2.1 pCi/L | 0.9 | Moderate | EPA Zone 3 | 3 |
| Nolan County | 2.1 pCi/L | 0.9 | Moderate | EPA Zone 3 | 6 |
| Sterling County | 2.1 pCi/L | 0.9 | Moderate | EPA Zone 3 | 1 |
| Potter County | 2.1 pCi/L | 1.2 | Moderate | EPA Zone 2 | 9 |
| Reagan County | 2.1 pCi/L | 0.9 | Moderate | EPA Zone 3 | 1 |
| Culberson County | 2.1 pCi/L | 1.1 | Moderate | EPA Zone 2 | 2 |
| San Saba County | 2.1 pCi/L | 1.1 | Moderate | EPA Zone 3 | 5 |
| Jack County | 2.1 pCi/L | 0.9 | Moderate | EPA Zone 3 | 4 |
| Stonewall County | 2.1 pCi/L | 1.1 | Moderate | EPA Zone 3 | 2 |
| Jeff Davis County | 2.1 pCi/L | 1.3 | Moderate | EPA Zone 2 | 2 |
| Crockett County | 2.0 pCi/L | 0.9 | Moderate | EPA Zone 3 | 2 |
| Scurry County | 2.0 pCi/L | 1.0 | Moderate | EPA Zone 3 | 3 |
| Childress County | 2.0 pCi/L | 0.9 | Moderate | EPA Zone 3 | 2 |
| Collingsworth County | 2.0 pCi/L | 0.9 | Moderate | EPA Zone 3 | 2 |
| Hall County | 2.0 pCi/L | 1.0 | Moderate | EPA Zone 3 | 4 |
| Lubbock County | 2.0 pCi/L | 0.9 | Moderate | EPA Zone 2 | 17 |
| Shackelford County | 2.0 pCi/L | 1.0 | Moderate | EPA Zone 3 | 3 |
| Eastland County | 2.0 pCi/L | 0.9 | Moderate | EPA Zone 3 | 7 |
| Reeves County | 2.0 pCi/L | 0.9 | Moderate | EPA Zone 2 | 2 |
| Howard County | 2.0 pCi/L | 0.9 | Moderate | EPA Zone 3 | 3 |
| Kimble County | 2.0 pCi/L | 0.8 | Moderate | EPA Zone 3 | 3 |
| Palo Pinto County | 2.0 pCi/L | 1.0 | Moderate | EPA Zone 3 | 6 |
| El Paso County | 2.0 pCi/L | 1.3 | Low | EPA Zone 3 | 25 |
| Hudspeth County | 2.0 pCi/L | 1.0 | Low | EPA Zone 2 | 2 |
| Llano County | 2.0 pCi/L | 1.1 | Low | EPA Zone 2 | 7 |
| Throckmorton County | 2.0 pCi/L | 1.0 | Low | EPA Zone 3 | 3 |
| Comanche County | 2.0 pCi/L | 0.9 | Low | EPA Zone 3 | 5 |
| Concho County | 2.0 pCi/L | 0.9 | Low | EPA Zone 3 | 4 |
| Hamilton County | 2.0 pCi/L | 0.9 | Low | EPA Zone 3 | 5 |
| Terrell County | 2.0 pCi/L | 0.8 | Low | EPA Zone 2 | 2 |
| Cottle County | 2.0 pCi/L | 0.9 | Low | EPA Zone 3 | 1 |
| Andrews County | 2.0 pCi/L | 0.8 | Low | EPA Zone 3 | 1 |
| Dawson County | 2.0 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Pecos County | 2.0 pCi/L | 0.9 | Low | EPA Zone 3 | 3 |
| Burnet County | 1.9 pCi/L | 1.0 | Low | EPA Zone 3 | 4 |
| Hardeman County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Motley County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 3 |
| Hockley County | 1.9 pCi/L | 0.8 | Low | EPA Zone 2 | 5 |
| Irion County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Lampasas County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Schleicher County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Upton County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Young County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 4 |
| Coleman County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 9 |
| Erath County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 4 |
| Johnson County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 10 |
| McCulloch County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Parker County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 11 |
| Blanco County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 4 |
| Brown County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 7 |
| Haskell County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 6 |
| Kent County | 1.9 pCi/L | 1.0 | Low | EPA Zone 3 | 2 |
| Montague County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 7 |
| Wilbarger County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 4 |
| Fannin County | 1.9 pCi/L | 1.0 | Low | EPA Zone 3 | 12 |
| Fisher County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 4 |
| Foard County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 1 |
| Wise County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 8 |
| Cochran County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Coke County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Edwards County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 1 |
| Gaines County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 4 |
| Jones County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Coryell County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Gillespie County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 4 |
| Grayson County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 15 |
| Baylor County | 1.9 pCi/L | 0.9 | Low | EPA Zone 3 | 1 |
| Kerr County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Clay County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Crane County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 1 |
| Winkler County | 1.9 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Menard County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Yoakum County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Bosque County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 8 |
| Kendall County | 1.8 pCi/L | 0.9 | Low | EPA Zone 3 | 5 |
| Martin County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Runnels County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Bandera County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Knox County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Lamar County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 11 |
| Terry County | 1.8 pCi/L | 0.7 | Low | EPA Zone 3 | 2 |
| Real County | 1.8 pCi/L | 0.7 | Low | EPA Zone 3 | 4 |
| Ward County | 1.8 pCi/L | 0.7 | Low | EPA Zone 3 | 4 |
| Ellis County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 11 |
| Taylor County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 12 |
| Tom Green County | 1.8 pCi/L | 0.7 | Low | EPA Zone 3 | 9 |
| Loving County | 1.8 pCi/L | 0.7 | Low | EPA Zone 3 | 1 |
| Hill County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 13 |
| Hood County | 1.8 pCi/L | 0.7 | Low | EPA Zone 3 | 4 |
| Midland County | 1.8 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Ector County | 1.7 pCi/L | 0.8 | Low | EPA Zone 3 | 7 |
| Val Verde County | 1.7 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Cooke County | 1.7 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Archer County | 1.7 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Comal County | 1.7 pCi/L | 0.9 | Low | EPA Zone 3 | 6 |
| Bell County | 1.7 pCi/L | 0.8 | Low | EPA Zone 3 | 17 |
| Somervell County | 1.7 pCi/L | 0.9 | Low | EPA Zone 3 | 3 |
| Uvalde County | 1.7 pCi/L | 0.7 | Low | EPA Zone 3 | 4 |
| Denton County | 1.7 pCi/L | 0.9 | Low | EPA Zone 3 | 24 |
| Medina County | 1.7 pCi/L | 0.7 | Low | EPA Zone 3 | 9 |
| Wichita County | 1.7 pCi/L | 0.8 | Low | EPA Zone 3 | 9 |
| Williamson County | 1.6 pCi/L | 0.9 | Low | EPA Zone 3 | 17 |
| Kinney County | 1.6 pCi/L | 0.7 | Low | EPA Zone 3 | 1 |
| Camp County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Collin County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 27 |
| Tarrant County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 62 |
| Wood County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Delta County | 1.6 pCi/L | 0.7 | Low | EPA Zone 3 | 5 |
| Franklin County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Robertson County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 4 |
| Van Zandt County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 8 |
| Morris County | 1.6 pCi/L | 0.9 | Low | EPA Zone 3 | 3 |
| Bastrop County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 8 |
| Cherokee County | 1.6 pCi/L | 0.9 | Low | EPA Zone 3 | 6 |
| McLennan County | 1.6 pCi/L | 0.7 | Low | EPA Zone 3 | 18 |
| Rusk County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 7 |
| Dallas County | 1.6 pCi/L | 0.9 | Low | EPA Zone 3 | 82 |
| Leon County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 7 |
| Falls County | 1.6 pCi/L | 0.7 | Low | EPA Zone 3 | 7 |
| San Augustine County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Wilson County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Burleson County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Freestone County | 1.6 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Lee County | 1.6 pCi/L | 0.7 | Low | EPA Zone 3 | 5 |
| Hays County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 7 |
| Rockwall County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 3 |
| Travis County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 47 |
| Cass County | 1.5 pCi/L | 0.9 | Low | EPA Zone 3 | 10 |
| Kaufman County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 8 |
| Upshur County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 4 |
| Guadalupe County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 6 |
| Limestone County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 7 |
| Maverick County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 2 |
| Rains County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Red River County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 6 |
| Gregg County | 1.5 pCi/L | 0.9 | Low | EPA Zone 3 | 7 |
| Lavaca County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Shelby County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 5 |
| Smith County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 14 |
| Angelina County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Atascosa County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 7 |
| Colorado County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 7 |
| Nacogdoches County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 8 |
| Titus County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 3 |
| Caldwell County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 5 |
| DeWitt County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Fayette County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 8 |
| Gonzales County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 8 |
| Harrison County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 8 |
| Henderson County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 10 |
| Hopkins County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 8 |
| Houston County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Hunt County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 9 |
| Milam County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 6 |
| Polk County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| San Jacinto County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Anderson County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Austin County | 1.5 pCi/L | 0.7 | Low | EPA Zone 3 | 6 |
| Madison County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Sabine County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Trinity County | 1.5 pCi/L | 0.9 | Low | EPA Zone 3 | 3 |
| Grimes County | 1.5 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Karnes County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Navarro County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 12 |
| Tyler County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 7 |
| Webb County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 8 |
| Frio County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 4 |
| Jackson County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 3 |
| Liberty County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 5 |
| Newton County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 6 |
| Panola County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 5 |
| Bowie County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 8 |
| Chambers County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 5 |
| Jasper County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 4 |
| Jim Hogg County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 1 |
| Montgomery County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 22 |
| Bexar County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 68 |
| Dimmit County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 3 |
| Marion County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 1 |
| Waller County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 3 |
| Aransas County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 1 |
| Brazoria County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 15 |
| Goliad County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 1 |
| Walker County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 3 |
| Washington County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 5 |
| Zavala County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 3 |
| Hardin County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 6 |
| La Salle County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 2 |
| Wharton County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 5 |
| Duval County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 4 |
| Live Oak County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 4 |
| Orange County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 4 |
| Bee County | 1.4 pCi/L | 0.7 | Low | EPA Zone 3 | 3 |
| Brazos County | 1.4 pCi/L | 0.8 | Low | EPA Zone 3 | 7 |
| Galveston County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 15 |
| Starr County | 1.4 pCi/L | 0.9 | Low | EPA Zone 3 | 6 |
| Calhoun County | 1.4 pCi/L | 0.6 | Low | EPA Zone 3 | 3 |
| Fort Bend County | 1.3 pCi/L | 0.6 | Low | EPA Zone 3 | 17 |
| Refugio County | 1.3 pCi/L | 0.6 | Low | EPA Zone 3 | 4 |
| Victoria County | 1.3 pCi/L | 0.6 | Low | EPA Zone 3 | 5 |
| Willacy County | 1.3 pCi/L | 0.8 | Low | EPA Zone 3 | 5 |
| Zapata County | 1.3 pCi/L | 0.8 | Low | EPA Zone 3 | 2 |
| Matagorda County | 1.3 pCi/L | 0.6 | Low | EPA Zone 3 | 9 |
| San Patricio County | 1.3 pCi/L | 0.6 | Low | EPA Zone 3 | 7 |
| Jefferson County | 1.3 pCi/L | 0.6 | Low | EPA Zone 3 | 14 |
| McMullen County | 1.3 pCi/L | 0.7 | Low | EPA Zone 3 | 2 |
| Brooks County | 1.3 pCi/L | 0.7 | Low | EPA Zone 3 | 2 |
| Jim Wells County | 1.3 pCi/L | 0.6 | Low | EPA Zone 3 | 3 |
| Harris County | 1.3 pCi/L | 0.6 | Low | EPA Zone 3 | 128 |
| Hidalgo County | 1.3 pCi/L | 0.7 | Low | EPA Zone 3 | 22 |
| Cameron County | 1.2 pCi/L | 0.6 | Low | EPA Zone 3 | 13 |
| Kleberg County | 1.2 pCi/L | 0.6 | Low | EPA Zone 3 | 3 |
| Kenedy County | 1.2 pCi/L | 0.7 | Low | EPA Zone 3 | 2 |
| Nueces County | 1.2 pCi/L | 0.6 | Low | EPA Zone 3 | 20 |
| King County | n/a | - | zone only | EPA Zone 3 | 0 |
Radon levels in Texas cities
The 83 most-populous Texas places among the 1,000 largest US cities (Census incorporated places and CDPs), by population. City figures are ZIP-land-weighted means of the model's ZIP predictions (model estimate).
| City | Population | Predicted basement | Upstairs | Grade | ZIPs ≥ 4 |
|---|---|---|---|---|---|
| Houston | 2,314,157 | 1.2 pCi/L | 0.5 | Low | 0% |
| San Antonio | 1,495,295 | 1.4 pCi/L | 0.6 | Low | 0% |
| Dallas | 1,302,868 | 1.5 pCi/L | 0.8 | Low | 0% |
| Austin | 979,882 | 1.5 pCi/L | 0.7 | Low | 0% |
| Fort Worth | 978,468 | 1.6 pCi/L | 0.8 | Low | 0% |
| El Paso | 678,958 | 2.0 pCi/L | 1.4 | Moderate | 0% |
| Arlington | 398,431 | 1.7 pCi/L | 0.9 | Low | 0% |
| Corpus Christi | 316,595 | 1.2 pCi/L | 0.6 | Low | 0% |
| Plano | 290,190 | 1.6 pCi/L | 0.8 | Low | 0% |
| Lubbock | 266,878 | 2.0 pCi/L | 0.9 | Moderate | 0% |
| Laredo | 257,602 | 1.5 pCi/L | 0.8 | Low | 0% |
| Irving | 254,373 | 1.6 pCi/L | 0.9 | Low | 0% |
| Garland | 243,470 | 1.5 pCi/L | 0.8 | Low | 0% |
| Frisco | 225,007 | 1.6 pCi/L | 0.9 | Low | 0% |
| McKinney | 213,509 | 1.8 pCi/L | 0.8 | Low | 0% |
| Amarillo | 202,408 | 2.2 pCi/L | 1.2 | Moderate | 0% |
| Grand Prairie | 202,134 | 1.7 pCi/L | 1.1 | Low | 0% |
| Brownsville | 190,158 | 1.3 pCi/L | 0.7 | Low | 0% |
| Killeen | 159,643 | 1.7 pCi/L | 0.8 | Low | 0% |
| Denton | 158,349 | 1.6 pCi/L | 0.8 | Low | 0% |
| Mesquite | 147,317 | 1.4 pCi/L | 0.8 | Low | 0% |
| Pasadena | 146,716 | 1.3 pCi/L | 0.6 | Low | 0% |
| McAllen | 146,593 | 1.2 pCi/L | 0.7 | Low | 0% |
| Waco | 144,816 | 1.6 pCi/L | 0.7 | Low | 0% |
| Midland | 138,397 | 1.8 pCi/L | 0.8 | Low | 0% |
| Lewisville | 133,553 | 1.6 pCi/L | 0.8 | Low | 0% |
| Carrollton | 132,918 | 1.7 pCi/L | 1.0 | Low | 0% |
| Round Rock | 130,406 | 1.7 pCi/L | 0.9 | Low | 0% |
| Abilene | 129,043 | 1.8 pCi/L | 0.8 | Low | 0% |
| Pearland | 127,736 | 1.4 pCi/L | 0.6 | Low | 0% |
| College Station | 125,192 | 1.4 pCi/L | 0.8 | Low | 0% |
| Richardson | 117,435 | 1.7 pCi/L | 0.9 | Low | 0% |
| League City | 116,320 | 1.4 pCi/L | 0.6 | Low | 0% |
| Odessa | 115,743 | 1.7 pCi/L | 0.7 | Low | 0% |
| Beaumont | 112,193 | 1.3 pCi/L | 0.6 | Low | 0% |
| Allen | 111,620 | 1.7 pCi/L | 0.8 | Low | 0% |
| New Braunfels | 110,958 | 1.5 pCi/L | 0.7 | Low | 0% |
| Tyler | 110,327 | 1.4 pCi/L | 0.8 | Low | 0% |
| Sugar Land | 108,515 | 1.3 pCi/L | 0.6 | Low | 0% |
| Conroe | 108,248 | 1.4 pCi/L | 0.7 | Low | 0% |
| Edinburg | 105,799 | 1.3 pCi/L | 0.7 | Low | 0% |
| Wichita Falls | 102,691 | 1.6 pCi/L | 0.8 | Low | 0% |
| San Angelo | 99,262 | 1.8 pCi/L | 0.7 | Low | 0% |
| Georgetown | 96,312 | 1.7 pCi/L | 0.9 | Low | 0% |
| The Woodlands | 93,847 | 1.4 pCi/L | 0.7 | Low | 0% |
| Temple | 93,095 | 1.7 pCi/L | 0.8 | Low | 0% |
| Bryan | 89,615 | 1.4 pCi/L | 0.8 | Low | 0% |
| Mission | 87,292 | 1.3 pCi/L | 0.8 | Low | 0% |
| Baytown | 84,067 | 1.3 pCi/L | 0.6 | Low | 0% |
| Longview | 83,236 | 1.4 pCi/L | 0.8 | Low | 0% |
| Pharr | 80,410 | 1.2 pCi/L | 0.6 | Low | 0% |
| Leander | 80,067 | 1.9 pCi/L | 0.9 | Low | 0% |
| Flower Mound | 79,445 | 1.7 pCi/L | 0.9 | Low | 0% |
| Mansfield | 78,542 | 1.8 pCi/L | 0.9 | Low | 0% |
| Cedar Park | 77,516 | 1.6 pCi/L | 0.9 | Low | 0% |
| Missouri City | 76,773 | 1.4 pCi/L | 0.6 | Low | 0% |
| San Marcos | 71,569 | 1.3 pCi/L | 0.5 | Low | 0% |
| Harlingen | 71,510 | 1.3 pCi/L | 0.6 | Low | 0% |
| North Richland Hills | 70,658 | 1.8 pCi/L | 1.0 | Low | 0% |
| Rowlett | 66,813 | 1.5 pCi/L | 0.7 | Low | 0% |
| Atascocita | 65,844 | 1.4 pCi/L | 0.6 | Low | 0% |
| Victoria | 65,800 | 1.4 pCi/L | 0.6 | Low | 0% |
| Pflugerville | 65,301 | 1.5 pCi/L | 0.7 | Low | 0% |
| Kyle | 62,548 | 1.5 pCi/L | 0.6 | Low | 0% |
| Wylie | 61,078 | 1.6 pCi/L | 0.7 | Low | 0% |
| Euless | 59,686 | 1.7 pCi/L | 1.0 | Low | 0% |
| Little Elm | 58,496 | 1.7 pCi/L | 0.9 | Low | 0% |
| Texas City | 56,609 | 1.4 pCi/L | 0.6 | Low | 0% |
| DeSoto | 55,740 | 1.8 pCi/L | 0.9 | Low | 0% |
| Port Arthur | 55,547 | 1.3 pCi/L | 0.6 | Low | 0% |
| Burleson | 55,220 | 1.9 pCi/L | 0.9 | Low | 0% |
| Spring | 54,298 | 1.3 pCi/L | 0.6 | Low | 0% |
| Galveston | 53,237 | 1.3 pCi/L | 0.7 | Low | 0% |
| Rockwall | 52,918 | 1.5 pCi/L | 0.7 | Low | 0% |
| Grapevine | 50,928 | 1.7 pCi/L | 0.8 | Low | 0% |
| Huntsville | 48,552 | 1.4 pCi/L | 0.8 | Low | 0% |
| Cedar Hill | 48,411 | 1.9 pCi/L | 0.9 | Low | 0% |
| Bedford | 48,370 | 1.7 pCi/L | 1.0 | Low | 0% |
| Sherman | 47,473 | 1.9 pCi/L | 1.0 | Low | 0% |
| Waxahachie | 47,201 | 1.8 pCi/L | 0.9 | Low | 0% |
| Keller | 46,316 | 1.7 pCi/L | 1.0 | Low | 0% |
| The Colony | 45,471 | 1.7 pCi/L | 0.8 | Low | 0% |
| Haltom City | 45,290 | 1.4 pCi/L | 0.7 | Low | 0% |
Highest-radon ZIP codes in Texas
The 10 Texas ZIP codes with the highest predicted basement average (model estimate), out of 1,713 modeled. A ZIP average is still an area figure - neighboring homes routinely test several pCi/L apart.
| ZIP | County | Predicted basement | Upstairs | Grade |
|---|---|---|---|---|
| 79040 | Hansford County | 2.7 pCi/L | 1.6 | Moderate |
| 79118 | Randall County | 2.6 pCi/L | 1.4 | Moderate |
| 79014 | Hemphill County | 2.5 pCi/L | 1.4 | Moderate |
| 79083 | Hutchinson County | 2.5 pCi/L | 1.3 | Moderate |
| 79005 | Lipscomb County | 2.5 pCi/L | 1.3 | Moderate |
| 79068 | Carson County | 2.5 pCi/L | 1.4 | Moderate |
| 79015 | Randall County | 2.5 pCi/L | 1.4 | Moderate |
| 79034 | Lipscomb County | 2.5 pCi/L | 1.4 | Moderate |
| 79029 | Moore County | 2.5 pCi/L | 1.4 | Moderate |
| 79070 | Ochiltree County | 2.5 pCi/L | 1.4 | Moderate |
Texas radon questions
- Is radon high in Texas?
- Texas's population-weighted predicted basement average is 1.5 pCi/L, about 16% below the US average of 1.8. 0 of its 253 modeled counties are predicted at or above the EPA action level of 4 pCi/L, 61 are in the 2-4 "consider fixing" range and 192 are below 2. 0% of Texas ZIP codes are predicted at 4 or higher.
- Which Texas county has the highest radon?
- Hemphill County has the highest predicted basement average in Texas at 2.5 pCi/L (EPA Zone 2). The lowest is Nueces County at 1.2 pCi/L. These are area figures; individual homes in any county can test far higher.
- How many EPA Zone 1 counties are in Texas?
- 0 of Texas's 254 counties (0%) are EPA Zone 1 (highest potential), 39 are Zone 2 and 215 are Zone 3. The EPA zone map dates from 1993; the predicted values on this page come from a 2001-2021 model built on millions of actual tests, so the two can disagree for a given county.
- Should I test for radon in Texas?
- Yes. Even though Texas's predicted average is below 2 pCi/L, the EPA recommends every home be tested - radon varies house to house, and 11.7% of Texas ZIP codes are still predicted at 2 pCi/L or higher.
Texas radon program
State programs keep lists of certified testers and mitigators and sometimes run kit programs. We link only pages we could verify, and Texas's program page did not respond when we checked, so start from the EPA state radon contacts page. Then read how to test and what mitigation costs.