| 1 | SC | Shandong Airlines | ICAO: CDG, Callsign: Shandong, IATA Prefix: 324, | PRC | AVCODES |
| 2 | SC | Servicos Aereos Cruzeiro Do Sul, S.A. | ICAO: CRZ, Callsign: Cruzeiro, Founded in 1927 as Syndicato Condor. Commenced operations in 1928. Ceased operations during 1993. | BR | AVCODES |
| 3 | SC | Sullivan County R.R. (Boston & Maine R.R.) | 8/1920-7/1923 | | NAKINA |
| 4 | SC | Sumter & Choctaw Ry. Co. | 1/1975-1/1980; eliminated 1/1986 | | NAKINA |
| 5 | SC | Sumter & Choctaw Ry. Co. | 1/75-1/80; eliminated 1/86 | | NRHS |
| 6 | SC | *BOSTON & MAINE RAILROAD [SULLIVAN COUNTY RAILROAD] | | | PWRC |
| 7 | SC | *SUMPTER & CHOCTAW RAILWAY | | | PWRC |
| 8 | SC | Sumter and Choctaw Railway | | | RSRV |
| 9 | SC | Southern Railway | 1999: 710km standard gauge, electrified at 750V= 3rd rail Southern (New Southern Railway Ltd.) is the latest name of the train operating company that took over from Connex South Central on the routes to South London, Surrey, and Sussex from Victoria and London Bridge. On 30 May 2004, the franchise was rebranded as Southern.. Southern also operates the cross-London Watford Junction to Gatwick Airport / Brighton route via Kensington (Olympia) and Clapham Junction (the West London Line). The franchise is owned by Govia, a joint venture between transport groups Go-Ahead Group and Keolis. | GB | TRAFFIC |
| 10 | SC | South Central (New Southern Railway) | | UK | VKM |
| 11 | SCA | South Central Air, Inc. | Callsign: South Central, | USA | AVCODES |
| 12 | SCA | South Central Air, Inc. | IATA: XE, Designator recalled by IATA | USA | AVCODES |
| 13 | SCA | Sierra Charlie Aviation, LLC | Callsign: Aviator, | USA | AVCODES |
| 14 | SCA | South Central Air | | | ICAO1 |
| 15 | SCAB | SCHIFFAHRTSKONTOR ALTES LAND GMBH & | | | SCAC4 |
| 16 | SCAD | SCANDIA EXPRESS INC | | | SCAC4 |
| 17 | SCAF | SCARLETT TRUCKING | | | SCAC4 |
| 18 | SCAG | SCR AIR SERVICE INC | | | SCAC4 |
| 19 | SCAH | SCHWAB, TIM R INC | | | SCAC4 |
| 20 | SCAI | SPENCER, C A INC | | | SCAC4 |
| 21 | SCAJ | SEA CAP INC | | | SCAC4 |
| 22 | SCAL | SCANDANAVIAN-AMERICAN LINES | | | PWRC |
| 23 | SCAL | S C ALPHA | | | SCAC4 |
| 24 | SCAN | SCANNAVINO, AL, TRUCKING, INC | | | SCAC1 |
| 25 | SCAN | SCANNAVINO, AL, TRUCKING | | | SCAC4 |
| 26 | SCANIA | Scania | | S | TRAFFIC |
| 27 | SCARD | Scarsdale Bus Company | | US-NY | TRAFFIC |
| 28 | SCAS | SOUTHERN CALIFORNIA MOVING & STORAG | | | SCAC4 |
| 29 | SCAT | SCAT DIVISION OF ABF FREIGHT | | | SCAC4 |
| 30 | SCAT | South Coast Area Transit | | US-CA | TRAFFIC |
| 31 | SCAU | SCA TRANSFOREST | | | SCAC4 |
| 32 | SCAW | SHADOWFAX CORPORATION, THE | | | SCAC4 |
| 33 | SCAX | Union Tank Car Co. | added 7/1956; 10/1957; eliminated 1/1958 | | NAKINA |
| 34 | SCAX | Shell Canada Ltd. | 10/1966 (not listed); added 4/1967; 4/1970-1/1980; eliminated 7/1981 | | NAKINA |
| 35 | SCAX | Shell Oil Co. of Canada, Ltd. | 7/1935-7/1954; eliminated 7/1956 | | NAKINA |
| 36 | SCAX | Shell Oil Co. of Canada, Ltd. | 4/38-1/52; eliminated 7/56 | | NRHS |
| 37 | SCAX | Union Tank Car Co. | added 7/56; 10/57; eliminated 1/58 | | NRHS |
| 38 | SCAX | Shell Canada Ltd. | added 4/67; 4/70-1/80; eliminated 7/81 | | NRHS |
| 39 | SCAX | *SHELL CANADA LTD. (UNION TANK CAR CO.) | | | PWRC |
| 40 | SCAX | *SOUTHERN CALIFORNIA REGIONAL RAIL AUTHORITY | | | PWRC |
| 41 | SCAX | Southern California Regional Rail Authority | | | RSRV |
| 42 | SCAX | SOUTHERN CALIFORNIA REGIONAL RAIL A | | | SCAC4 |
| 43 | SCAX | Metrolink, Southern California Regional Rail Authority | | USA | TRAFFIC |
| 44 | SCAZ | ASSIGNED FOR ATP | | | PWRC |
| 45 | SCB | Sky Cabs (PVT) Ltd. | IATA: 2E, Callsign: Sky Cabs, Designator 2E recalled by IATA | CL | AVCODES |
| 46 | SCB | Sky Cabs (PVT) Ltd. | Callsign: Sky Cabs, Designator 2E recalled by IATA | CL | AVCODES |
| 47 | SCB | | | CH | TRAFFIC |
| 48 | SCBG | Santa Cruz, Big Trees & Pacific Ry. Co. | 1/1994-7/2005 | | NAKINA |
| 49 | SCBG | Santa Cruz, Big Trees & Pacific Ry. Co. | 1/94-7/2000 | | NRHS |
| 50 | SCBG | SANTA CRUZ, BIG TREES & PACIFIC RAILWAY | | | PWRC |
| 51 | SCBG | Santa Cruz, Big Trees and Pacific Railway | | | RSRV |
| 52 | SCBJ | SCHNACKER, LAYNE TRUCKING INC | | | SCAC4 |
| 53 | SCBP | SCHAFER BROS. TRANSFER & PIANO MOVERS, INC | | | SCAC1 |
| 54 | SCBP | SCHAFER BROS TRANSFER & PIANO MOVER | | | SCAC4 |
| 55 | SCBR | SCHULTZ, BRUCE TRUCKING | | | SCAC4 |
| 56 | SCBS | SOLUTIONS LOGISTICS INC | | | SCAC4 |
| 57 | SCBT | SHIPPER CENTRAL INC | | | SCAC4 |
| 58 | SCBU | SCANDI BULK AB | | S | BIC |
| 59 | SCBV | SCIENTIFIC CREATIONS | | | SCAC4 |
| 60 | SCBX | Standbridge Color Corp. | added 7/1997; 7/2000-7/2005 | | NAKINA |
| 61 | SCBX | Shell Oil Co. of British Columbia, Ltd. | 7/1930-1/1950 | | NAKINA |
| 62 | SCBX | Shell Oil Co. of British Columbia, Ltd. | Apr-38 | | NRHS |
| 63 | SCBX | Standbridge Color Corp. | added 7/97; 7/2000 | | NRHS |
| 64 | SCBX | *SHELL OIL CO. OF BRITISH COLUMBIA, LTD. | | | PWRC |
| 65 | SCBX | +STANDBRIDGE COLOR CORPORATION | | | PWRC |
| 66 | SCBX | Standbridge Color Corporation | | | RSRV |
| 67 | SCBX | STANDRIDGE COLOR CORPORATION | | | SCAC4 |
| 68 | SCBY | SCHOBER, KENNY TRANSPORT INC | | | SCAC4 |
| 69 | SCC | Seacoast Airlines, Inc. | Callsign: Sea-Coaster, | USA | AVCODES |
| 70 | SCC | Seacoast Airlines | | | ICAO1 |
| 71 | SCC | Susquehanna Coal Co. | | USA | TRAFFIC |
| 72 | SCCA | SCHINDLER CARVINGS | | | SCAC4 |
| 73 | SCCB | STONEY CREEK CABINET COMPANY | | | SCAC4 |
| 74 | SCCC | SPECIFIED COMMODITY CARRIERS INC | | | SCAC4 |
| 75 | SCCG | SCHNIDT CARTAGE INC | | | SCAC4 |
| 76 | SCCI | SLACK CHEMICAL COMPANY INC | | | SCAC4 |
| 77 | SCCL | SOUTH C & C TRUCKING LLC | | | SCAC4 |
| 78 | SCCM | SIEM CAR CARRIERS (PACIFIC) AS | | | SCAC4 |
| 79 | SCCN | SOUTHERN CROSS CARRIERS INC | | | SCAC4 |
| 80 | SCCO | SENTER CARTAGE COMPANY INC | | | SCAC4 |
| 81 | SCCON | Scandicon AB | | SE | VKM |
| 82 | SCCP | SUN FUELS INC | | | SCAC4 |
| 83 | SCCR | SURPASS CHEMICAL CO INC | | | SCAC4 |
| 84 | SCCT | SANTA CLARA COUNTY TRANSIT DISTRICT | | | PWRC |
| 85 | SCCT | SUTCO CONTRACTING LTD | | | SCAC4 |
| 86 | SCCTD | Santa Clara County Transit District | City: San Jose | US-CA | TRAFFIC |
| 87 | SCCU | SUDAN SHIPPING LINE CO LTD | | SUD | BIC |
| 88 | SCCU | CIE SCADOA | | | SCAC3 |
| 89 | SCCU | SEA CONTAINERS LTD | | | SCAC4 |
| 90 | SCCV | SCHUMM TRUCKING | | | SCAC4 |
| 91 | SCCW | SCARECROW TRANSPORTATION LLC | | | SCAC4 |
| 92 | SCCX | Shell Oil Co. | added 10/1953; 7/1954-1/1980; eliminated 1/1980 | | NAKINA |
| 93 | SCCX | Shell Oil Co. | 7/1937-4/1938 | | NAKINA |
| 94 | SCCX | Shell Oil Co., Inc. | 1/1941-1/1952; eliminated 10/1953 | | NAKINA |
| 95 | SCCX | Shell (Shell Oil Co.) | 7/1935 | | NAKINA |
| 96 | SCCX | Shell Co. of California (Shell Oil Co.) | 7/1930-7/1932 | | NAKINA |
| 97 | SCCX | Shell Co. of California | 8/1920-7/1923 | | NAKINA |
| 98 | SCCX | Shell Oil Co., Inc. | 4/38-1/52; eliminated 10/53 | | NRHS |
| 99 | SCCX | Shell Oil Co. | added 10/53; 10/57-1/80; eliminated 1/80 | | NRHS |
| 100 | SCCX | *(SOEX) SHELL OIL COMPANY | | | PWRC |
