| | Cottle County | TX | 48101 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=CottleCounty+TX |
| | Crane County | TX | 48103 | | | | | nonmetro county (rural) | mining-dependent | https://maps.google.com/?q=CraneCounty+TX |
| | Crockett County | TX | 48105 | | | | | nonmetro county (rural) | mining-dependent | https://maps.google.com/?q=CrockettCounty+TX |
| | Crosby County | TX | 48107 | | Lubbock, TX 31180 | Lubbock-Plainview, TX 352 | Outlying | metro county (urban) | farm-dependent | https://maps.google.com/?q=CrosbyCounty+TX |
| | Culberson County | TX | 48109 | | | | | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=CulbersonCounty+TX |
| | Dallam County | TX | 48111 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=DallamCounty+TX |
| | Dallas County | TX | 48113 | Dallas-Plano-Irving, TX 19124 | Dallas-Fort
Worth-Arlington, TX 19100 | Dallas-Fort Worth, TX-OK 206 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=DallasCounty+TX |
| | Dawson County | TX | 48115 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=DawsonCounty+Texas |
| | Deaf Smith County | TX | 48117 | | Hereford, TX 25820 | | Central | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=DeafSmithCounty+TX |
| | Delta County | TX | 48119 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=DeltaCounty+TX |