| | | St. Louis County | MO | 29189 | | St. Louis, MO-IL 41180 | St. Louis-St.
Charles-Farmington, MO-IL 476 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=St.LouisCounty+MO |
| | | Warren County | MO | 29219 | | St. Louis, MO-IL 41180 | St. Louis-St.
Charles-Farmington, MO-IL 476 | Outlying | metro county (urban) | manufacturing-dependent | https://maps.google.com/?q=WarrenCounty+MO |
| | | Webster County | MO | 29225 | | Springfield, MO 44180 | | Outlying | metro county (urban) | nonspecialized | https://maps.google.com/?q=WebsterCounty+Missouri |
| | | St. Louis city | MO | 29510 | | St. Louis, MO-IL 41180 | St. Louis-St.
Charles-Farmington, MO-IL 476 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=St.Louiscity+MO |
| | | Adair County | MO | 29001 | | Kirksville, MO 28860 | | Central | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=AdairCounty+MO |
| | | Atchison County | MO | 29005 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=AtchisonCounty+MO |
| | | Audrain County | MO | 29007 | | Mexico, MO 33020 | Columbia-Jefferson
City-Moberly, MO 190 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=AudrainCounty+MO |
| | | Barry County | MO | 29009 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=BarryCounty+MO |
| | | Barton County | MO | 29011 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=BartonCounty+MO |
| | | Benton County | MO | 29015 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=BentonCounty+MO |
