| | Marshall County | IN | 18099 | | Plymouth, IN 38500 | South
Bend-Elkhart-Mishawaka,
IN-MI 515 | Central | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=MarshallCounty+IN |
| | Martin County | IN | 18101 | | | | | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=MartinCounty+IN |
| | Miami County | IN | 18103 | | Peru, IN 37940 | Indianapolis-Carmel-Muncie,
IN 294 | Central | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=MiamiCounty+IN |
| | Montgomery County | IN | 18107 | | Crawfordsville, IN 18820 | Indianapolis-Carmel-Muncie,
IN 294 | Central | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=MontgomeryCounty+IN |
| | Noble County | IN | 18113 | | Kendallville, IN 28340 | Fort
Wayne-Huntington-Auburn,
IN 258 | Central | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=NobleCounty+IN |
| | Orange County | IN | 18117 | | | | | nonmetro county (rural) | recreation | https://maps.google.com/?q=OrangeCounty+IN |
| | Parke County | IN | 18121 | | | | | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=ParkeCounty+IN |
| | Perry County | IN | 18123 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=PerryCounty+IN |
| | Pike County | IN | 18125 | | | | | nonmetro county (rural) | mining-dependent | https://maps.google.com/?q=PikeCounty+IN |
| | Pulaski County | IN | 18131 | | | | | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=PulaskiCounty+IN |