| 1 | SCT | Saab-Aircraft AB | Callsign: Saab-Craft, Name changed from Saab-Scania AS | S | AVCODES |
| 2 | SCT | Saab-Scania AS | Callsign: Saab-Craft, Name changed to Saab-Aircraft AB | S | AVCODES |
| 3 | SCT | SAAB-Aircraft | | | ICAO1 |
| 4 | SCT | Sioux City Terminal Ry. | 1/1975-7/2005 | | NAKINA |
| 5 | SCT | Sioux City Terminal Ry. | 1/75-7/2000 | | NRHS |
| 6 | SCT | *SOUTH CENTRAL TENNESSEE RAILROAD | | | PWRC |
| 7 | SCT | +SIOUX CITY TERMINAL RAILWAY | | | PWRC |
| 8 | SCT | Sioux City Terminal Railway | | | RSRV |
| 9 | SCT | Specialized Container Transport | | AUS | TRAFFIC |
| 10 | SCTA | SCOTT TRANSPORTATION INC | | | SCAC4 |
| 11 | SCTB | SADDLE CREEK TRANSPORTATION INC (BR | | | SCAC4 |
| 12 | SCTC | Societá Cusiana Trasporti Costruzioni (Gossano) | | I | TRAFFIC |
| 13 | SCTD | Sheffield Corporation Transport Department | | GB | TRAFFIC |
| 14 | SCTE | SCOTT ENTERPRISES | | | SCAC4 |
| 15 | SCTI | SUPER CONTAINER TRANSPORT INC | | | SCAC4 |
| 16 | SCTL | STANS CHAPERONE/SHUTTLE SERVICE | | | SCAC4 |
| 17 | SCTM | SUNCOAST TRANSPORTATION INC | | | SCAC4 |
| 18 | SCTN | SMITH, CHARLES TRUCKING INCORPORATE | | | SCAC4 |
| 19 | SCTR | South Central Tennessee R.R. Co., Inc. | added 10/1978; added 10/1979; 1/1980-1/1994; eliminated 10/1994 | | NAKINA |
| 20 | SCTR | South Central Tennessee R.R. Corp. | added 10/1994; 7/2000; eliminated 4/2001 | | NAKINA |
| 21 | SCTR | SCTRR, LLC | added 4/2000; 7/2005 | | NAKINA |
| 22 | SCTR | South Central Tennessee R.R. Co., Inc. | added 10/78; 1/80-1/94; eliminated 10/94 | | NRHS |
| 23 | SCTR | South Central Tennessee R.R. Corp. | added 10/94; 7/2000; eliminated 4/2001 | | NRHS |
| 24 | SCTR | SCTRR, LLC | added 4/2000 | | NRHS |
| 25 | SCTR | SCTRR, LLC [SOUTH CENTRAL TENNESSEE RAILROAD CORPORATION] | | | PWRC |
| 26 | SCTR | South Central Tennessee Railroad | | | RSRV |
| 27 | SCTR | SCTRR LLC | | | SCAC4 |
| 28 | SCTS | S & C TRANSPORTATION | | | SCAC4 |
| 29 | SCTT | SCOTT TRUCK SYSTEMS INC | | | SCAC4 |
| 30 | SCTU | SOUTH COAST LOGISTICS LTD T/A SOUTH COAST | | IRL | BIC |
| 31 | SCTU | SHIRLSTAR CONTAINER TRANSPORT LTD. | | | PWRC |
| 32 | SCTU | Shirlstar Container Transport Limited | | | RSRV |
| 33 | SCTU | SOUTHCOAST TRANSPORT | | | SCAC4 |
| 34 | SCTV | SEACOAST TRANSPORTATION SERVICE INC | | | SCAC4 |
| 35 | SCTW | SCOTT-WILLIAMS INC | | | SCAC4 |
| 36 | SCTX | Steel Cities Chemical Co. | 8/1920-7/1932 | | NAKINA |
| 37 | SCTX | STEEL CITIES CHEMICAL CO. | | | PWRC |
| 38 | SCTY | SOUTHERN CHRISTIAN TRANSPORTATION I | | | SCAC4 |
