| | Stone County | MO | 29209 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=StoneCounty+Missouri |
| | Stoddard County | MO | 29207 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=StoddardCounty+MO |
| | Ste. Genevieve County | MO | 29186 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=Ste.GenevieveCounty+MO |
| | 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 |
| | 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 |
| | St. Francois County | MO | 29187 | | Farmington, MO 22100 | St. Louis-St.
Charles-Farmington, MO-IL 476 | Central | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=St.FrancoisCounty+MO |
| | St. Clair County | MO | 29185 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=St.ClairCounty+MO |
| | St. Charles County | MO | 29183 | | St. Louis, MO-IL 41180 | St. Louis-St.
Charles-Farmington, MO-IL 476 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=St.CharlesCounty+MO |
| | Shelby County | MO | 29205 | | | | | nonmetro county (rural) | farm-dependent | https://maps.google.com/?q=ShelbyCounty+MO |
| | Shannon County | MO | 29203 | | | | | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=ShannonCounty+MO |