| HHebron | Hebron | OH | Plastics and Rubber Products Manufacturing326112 | 100-499 | ◐ LIKELY ACTIVE |
| HAHeico Aerospace Parts CORP. | Cleveland | OH | Transportation Equipment Manufacturing336412 | — | ◐ LIKELY ACTIVE |
| HMHelgeson, Michael | Sandusky | OH | Transportation Equipment Manufacturing336412 | — | ◐ LIKELY ACTIVE |
Henderson Products - Upfit Service Center Bucyrus | Bucyrus | OH | Transportation Equipment Manufacturing336211 | 20-99 | ◐ LIKELY ACTIVE |
| HTHeritage Truck Equipment | Hartville | OH | Transportation Equipment Manufacturing336211 | 100-499 | ◐ LIKELY ACTIVE |
| HEHits Engineering INC. | Cincinnati | OH | Transportation Equipment Manufacturing336411 | — | ◐ LIKELY ACTIVE |
| HMHKK Machining Company | West Unity | OH | Transportation Equipment Manufacturing336370 | 1-19 | ◐ LIKELY ACTIVE |
| HHoneywell | US, OH, Urbana | OH | Transportation Equipment Manufacturing336413 | 500+ | ◐ LIKELY ACTIVE |
| HNHSM New Washington (212) | New Washington | OH | Transportation Equipment Manufacturing336360 | 20-99 | ◐ LIKELY ACTIVE |
| HSHydro Sidney | Sidney | OH | Transportation Equipment Manufacturing336211 | 100-499 | ◐ LIKELY ACTIVE |
| IMIntegrated Manufacturing Additive Technology Center | West Chester | OH | Transportation Equipment Manufacturing336412 | 100-499 | ◐ LIKELY ACTIVE |
| IMIntegrated Manufacturing DCCDayton | Dayton | OH | Transportation Equipment Manufacturing336412 | 20-99 | ◐ LIKELY ACTIVE |
| JMJAC Manufacturing Napoleon | Napoleon | OH | Transportation Equipment Manufacturing336390 | 100-499 | ◐ LIKELY ACTIVE |
| JTJAE Tech, Inc. | Apple Creek | OH | Transportation Equipment Manufacturing336350 | 20-99 | ◐ LIKELY ACTIVE |
| KLKD Lamp | Andover | OH | Transportation Equipment Manufacturing336112 | 20-99 | ◐ LIKELY ACTIVE |
| KAKirchhoff Automotive | Waverly | OH | Transportation Equipment Manufacturing336370 | 100-499 | ◐ LIKELY ACTIVE |
| KCKks Contracting LLC | Ashland | OH | Transportation Equipment Manufacturing336212 | — | ◐ LIKELY ACTIVE |
| KTKnapheide Truck Equipment Company | Cincinnati | OH | Transportation Equipment Manufacturing336211 | 20-99 | ◐ LIKELY ACTIVE |
| KTKnapheide Truck Equipment Company Columbus | Columbus | OH | Transportation Equipment Manufacturing336211 | 20-99 | ◐ LIKELY ACTIVE |
| LFLacks Forgeline LLC | Dayton | OH | Transportation Equipment Manufacturing336390 | 20-99 | ◐ LIKELY ACTIVE |
| LTLawrence Technologies INC | Dayton | OH | Transportation Equipment Manufacturing336320 | — | ◐ LIKELY ACTIVE |
| LWLeffel Works | Springfield | OH | Transportation Equipment Manufacturing336370 | 100-499 | ◐ LIKELY ACTIVE |
| LCLORD Corporation - Dayton | Dayton | OH | Transportation Equipment Manufacturing336413 | 100-499 | ◐ LIKELY ACTIVE |
| MSMagna Seating Columbus | Lancaster | OH | Transportation Equipment Manufacturing336360 | 500+ | ◐ LIKELY ACTIVE |
| MBMahle Behr Dayton | 1600 Webster Street Dayton, Ohio | OH | Transportation Equipment Manufacturing336390 | 500+ | ◐ LIKELY ACTIVE |
| MTManufacturing & Technical Support Services LLC | Beavercreek | OH | Transportation Equipment Manufacturing336413 | — | ◐ LIKELY ACTIVE |
| MNMarelli North America, Inc. | Bowling Green | OH | Transportation Equipment Manufacturing336360 | 20-99 | ◐ LIKELY ACTIVE |
| MWMartin Wheel | Tallmadge | OH | Transportation Equipment Manufacturing336999 | 20-99 | ◐ LIKELY ACTIVE |
| MIMaval Industries | Twinsburg | OH | Transportation Equipment Manufacturing336330 | 100-499 | ◐ LIKELY ACTIVE |
| MWMaval Warehouse | Maple Heights | OH | Transportation Equipment Manufacturing336330 | 1-19 | ◐ LIKELY ACTIVE |
| MRMiddletown Recycling | Middletown | OH | Transportation Equipment Manufacturing336510 | 1-19 | ◐ LIKELY ACTIVE |
| MIMillat Industries, CORP. | Kettering | OH | Transportation Equipment Manufacturing336412 | — | ◐ LIKELY ACTIVE |
| MSMohr Stamping INC. | Wellington | OH | Transportation Equipment Manufacturing336370 | 20-99 | ◐ LIKELY ACTIVE |
| MYMotherson Yachiyo US Automotive Systems, Inc | Marion | OH | Transportation Equipment Manufacturing336390 | 100-499 | ◐ LIKELY ACTIVE |
| NFNational Fleet Services of Ohio | Avon Lake | OH | Transportation Equipment Manufacturing336212 | 100-499 | ◐ LIKELY ACTIVE |
| NTNewark Trucking | Newark | OH | Transportation Equipment Manufacturing336999 | 1-19 | ◐ LIKELY ACTIVE |
| NNgas-oh12 | Kettering | OH | Transportation Equipment Manufacturing336413 | 20-99 | ◐ LIKELY ACTIVE |
| NINorplas Industries (Magna T.E.A.M. Systems) | Toledo | OH | Transportation Equipment Manufacturing336390 | 100-499 | ◐ LIKELY ACTIVE |
| NCNSI Crankshaft | Fostoria | OH | Transportation Equipment Manufacturing336310 | 20-99 | ◐ LIKELY ACTIVE |
| OTOakley - Toledo | Northwood | OH | Transportation Equipment Manufacturing336390 | 20-99 | ◐ LIKELY ACTIVE |
| OIOgs Industries, INC | Akron | OH | Transportation Equipment Manufacturing336412 | — | ▲ REPORTED CLOSED |
| OTOhashi Technica USA Manufacturing Inc | Sunbury | OH | Transportation Equipment Manufacturing336390 | 20-99 | ◐ LIKELY ACTIVE |
| OAOhio Assembly | Avon Lake | OH | Transportation Equipment Manufacturing336211 | 500+ | ◐ LIKELY ACTIVE |
| OOOhio Office | Columbus | OH | Transportation Equipment Manufacturing336320 | 20-99 | ◐ LIKELY ACTIVE |
| OPOhio Precision Products LLC | Toledo | OH | Transportation Equipment Manufacturing336390 | 1-19 | ◐ LIKELY ACTIVE |
| PCParker-hannifin Corporation | Mentor | OH | Transportation Equipment Manufacturing336413 | — | ◐ LIKELY ACTIVE |
| PTPAS Technologies Inc. dba StandardAero | Hillsboro | OH | Transportation Equipment Manufacturing336412 | 100-499 | ◐ LIKELY ACTIVE |
| PTPegasus Trailers INC. | Sandusky | OH | Transportation Equipment Manufacturing336212 | — | ▲ REPORTED CLOSED |
Piston Automotive - Toledo | Toledo | OH | Transportation Equipment Manufacturing336390 | 100-499 | ◐ LIKELY ACTIVE |
| PMPJ Mt Orab | Mount Orab | OH | Transportation Equipment Manufacturing336212 | 100-499 | ◐ LIKELY ACTIVE |