| | Adair County | OK | 40001 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=AdairCounty+OK |
| | Alfalfa County | OK | 40003 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=AlfalfaCounty+OK |
| | Atoka County | OK | 40005 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=AtokaCounty+OK |
| | Beaver County | OK | 40007 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=BeaverCounty+OK |
| | Beckham County | OK | 40009 | | Elk City, OK 21120 | Weatherford-Elk City, OK 555 | Central | nonmetro county (rural) | mining-dependent | https://maps.google.com/?q=BeckhamCounty+OK |
| | Blaine County | OK | 40011 | | | | | nonmetro county (rural) | mining-dependent | https://maps.google.com/?q=BlaineCounty+OK |
| | Bryan County | OK | 40013 | | Durant, OK 20460 | Dallas-Fort Worth, TX-OK 206 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=BryanCounty+OK |
| | Caddo County | OK | 40015 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=CaddoCounty+OK |
| | Canadian County | OK | 40017 | | Oklahoma City, OK 36420 | Oklahoma City-Shawnee, OK 416 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=CanadianCounty+OK |
| | Carter County | OK | 40019 | | Ardmore, OK 11620 | | Central | nonmetro county (rural) | mining-dependent | https://maps.google.com/?q=CarterCounty+OK |