| | | Allen County | OH | 39003 | | Lima, OH 30620 | Lima-Van Wert-Celina, OH 338 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=AllenCounty+OH |
| | | Ashland County | OH | 39005 | | Ashland, OH 11740 | Mansfield-Ashland-Bucyrus,
OH 360 | Central | nonmetro county (rural) | nonspecialized | https://maps.google.com/?q=AshlandCounty+OH |
| | | Ashtabula County | OH | 39007 | | Ashtabula, OH 11780 | Cleveland-Akron-Canton,
OH 184 | Central | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=AshtabulaCounty+OH |
| | | Athens County | OH | 39009 | | Athens, OH 11900 | | Central | nonmetro county (rural) | federal/state
government-dependent | https://maps.google.com/?q=AthensCounty+OH |
| | | Auglaize County | OH | 39011 | | Wapakoneta, OH 47540 | Lima-Van Wert-Celina, OH 338 | Central | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=AuglaizeCounty+OH |
| | | Belmont County | OH | 39013 | | Wheeling, WV-OH 48540 | | Central | metro county (urban) | mining-dependent | https://maps.google.com/?q=BelmontCounty+OH |
| | | Butler County | OH | 39017 | | Cincinnati, OH-KY-IN 17140 | Cincinnati-Wilmington-Maysville,
OH-KY-IN 178 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=ButlerCounty+OH |
| | | Champaign County | OH | 39021 | | Urbana, OH 46500 | Dayton-Springfield-Sidney,
OH 212 | Central | nonmetro county (rural) | manufacturing-dependent | https://maps.google.com/?q=ChampaignCounty+OH |
| | | Clark County | OH | 39023 | | Springfield, OH 44220 | Dayton-Springfield-Sidney,
OH 212 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=ClarkCounty+OH |
| | | Clermont County | OH | 39025 | | Cincinnati, OH-KY-IN 17140 | Cincinnati-Wilmington-Maysville,
OH-KY-IN 178 | Central | metro county (urban) | nonspecialized | https://maps.google.com/?q=ClermontCounty+OH |
