| RTRail Terminal Services | French Camp | CA | — | ◇ UNVERIFIED |
| RHRed Haul Express LLC | Yucaipa | CA | — | ◇ UNVERIFIED |
| RLRelco Locomotives Incorporated | Albia | IA | — | ◇ UNVERIFIED |
| RGRescar Gordon Facility | Gordon | GA | — | ◇ UNVERIFIED |
| RARetrofit and Cleaning Rack Expansion | Marmaduke | AR | — | ◇ UNVERIFIED |
| RMRocky Mountain Rail Car & Repair INC | Tooele | UT | — | ◇ UNVERIFIED |
| STSabre Tubular Structures | Fort Worth | TX | — | ◇ UNVERIFIED |
| SFSan Francisco Bay Railway | San Francisco | CA | — | ◇ UNVERIFIED |
| SEScott Equiment INC | Santa Fe Springs | CA | — | ◇ UNVERIFIED |
| SISeisenbacher, INC. | Rochester | NY | — | ◇ UNVERIFIED |
| SGSeminole Gulf Railway | Fort Myers | FL | — | ◇ UNVERIFIED |
 Siemens Industry INC | Saint Paul | MN | — | ◇ UNVERIFIED |
| Siemens Industry INC | Mcclellan Park | CA | — | ◇ UNVERIFIED |
| Siemens Industry, INC | Sacramento | CA | — | ◇ UNVERIFIED |
| SMSiemens Mobility INC | Sacramento | CA | — | ◇ UNVERIFIED |
| SMSiemens Mobility INC | Oakland | CA | — | ◇ UNVERIFIED |
| SMSiemens Mobility, INC | Lexington | NC | — | ◇ UNVERIFIED |
| SMSiemens Mobility INC Midway | Sacramento | CA | — | ◇ UNVERIFIED |
| SGSims Grading INC | Vista | CA | — | ◇ UNVERIFIED |
| SJSocal Jcb | Fontana | CA | — | ◇ UNVERIFIED |
| SRSoutheastern Railway Services | Magnolia | MS | — | ◇ UNVERIFIED |
| SPSouthern Pacific Lines | Denver | CO | — | ◇ UNVERIFIED |
| SWSouth Western Sealcoating INC | Murrieta | CA | — | ◇ UNVERIFIED |
| SEStadler Expansion | Salt Lake City | UT | — | ◇ UNVERIFIED |
| SRStucki Roller Bearing Company | Glendale | KY | — | ◇ UNVERIFIED |
| SRStucki Roller Bearing - Nebraska | Lincoln | NE | — | ◇ UNVERIFIED |
| SCSully-miller Contracting CO Bl | Long Beach | CA | — | ◇ UNVERIFIED |
| SSunbelt | Newhall | CA | — | ◇ UNVERIFIED |
| SBSwinerton Builders | Mendota | CA | — | ◇ UNVERIFIED |
| SRSygnet Rail Technologies LLC | Tenino | WA | — | ◇ UNVERIFIED |
| SRSygnet Rail Technologies Site | Tenino | WA | — | ◇ UNVERIFIED |
| TCTamper Corporation | West Columbia | SC | — | ◇ UNVERIFIED |
| TITeleweld INC | Streator | IL | — | ◇ UNVERIFIED |
| TCThrall Car Manufacturing Company | Cartersville | GA | — | ◇ UNVERIFIED |
| TLTig/m, LLC | Chatsworth | CA | — | ◇ UNVERIFIED |
| TBTnt Blanchard General Eingneering INC. | Winchester | CA | — | ◇ UNVERIFIED |
| TAToku American INC Dba Striker Hydraulic Breakers | Riverside | CA | — | ◇ UNVERIFIED |
| TSTrackside Services, INC. | Milwaukee | WI | — | ◇ UNVERIFIED |
| TRTransco Railway Products | Miles City | MT | — | ◇ UNVERIFIED |
| TRTransco Railway Products, INC - Oelwein | Oelwein | IA | — | ◇ UNVERIFIED |
| TRTransdev Rail INC | Riverside | CA | — | ◇ UNVERIFIED |
| TDTrinity Diversified INC | Gardena | CA | — | ◇ UNVERIFIED |
| TITrinity Industries, INC. | Hurst | TX | — | ◇ UNVERIFIED |
| TITrinity Industries, LLC | Cartersville | GA | — | ◇ UNVERIFIED |
| TITrinity Industries Plant 117 | Vidor | TX | — | ◇ UNVERIFIED |
| TITrinity Industries Plant 19 | Longview | TX | — | ◇ UNVERIFIED |
| TRTrinity Rail Maintenance Services, INC. | Vidor | TX | — | ◇ UNVERIFIED |
| TSTrinity Shoring Products, INC. | Union City | MI | — | ◇ UNVERIFIED |
| TTTrinity Tank Car INC Plt 194 | Longview | TX | — | ◇ UNVERIFIED |
| TFTriple F Industries LLC | Hopland | CA | — | ◇ UNVERIFIED |
