| Abbreviation | Definition |
|---|---|
| CS | Colorado and Southern Railway (BNSF Railway) |
| CSAU | Costa Line |
| CSBX | Cargill Incorporated - Salt Division |
| CSBX | Cargill Salt Division |
| CSCD | Cascade and Columbia River Railroad |
| CSCX | Coal Supply Corporation |
| CSDX | Metropolitan Water Reclamation District of Greater Chicago |
| CSGX | Central Sand and Gravel |
| CSIU | CSI Group |
| CSKR | C and S Railroad |
| CSKR | C and S Railroad Corporation |
| CSKU | Consolidated Services |
| CSKU | Consolidated Services Incorporated |
| CSL | Chicago Short Line Railway |
| CSL | Chicago Short Line Railway Company |
| CSL | Coastal Star Light |
| CSMX | Carol and Andy Muller |
| CSNX | Cities Service Oil and Gas Corporation (Trident NGL) |
| CSNX | Trident NGL Incorporated |
| CSO | Connecticut Southern Railroad |