| 1 | SPC | Skyworld Airlines | Callsign: Port, | USA | AVCODES |
| 2 | SPC | Skyworld Airlines | | | ICAO1 |
| 3 | SPC | SOUTHERN PACIFIC [SOUTH PACIFIC COAST RAILROAD] | | | PWRC |
| 4 | SPC | SPIRIT COACH LLC | | | SCAC4 |
| 5 | SPCA | SOPRO CARRIERS INC | | | SCAC4 |
| 6 | SPCC | SOUTHWESTERN PORTLAND CEMENT CO. | | | PWRC |
| 7 | SPCC | STAPLES OIL CO INC | | | SCAC4 |
| 8 | SPCC | Southern Peru Copper Corporation | | PE | TRAFFIC |
| 9 | SPCD | SPRINT COURIER INC | | | SCAC4 |
| 10 | SPCF | SPECIFIED FITTINGS INC | | | SCAC4 |
| 11 | SPCG | SPECIALIZED TRANSPORTATION INC | | | SCAC4 |
| 12 | SPCH | Quest Communications Corp. | 7/2000-7/2005 | | NAKINA |
| 13 | SPCH | Quest Communications Corp. | Jul-00 | | NRHS |
| 14 | SPCH | QUEST COMMUNICATIONS CORP. | | | PWRC |
| 15 | SPCH | Quest Communications Corporation | | | RSRV |
| 16 | SPCH | SUPREME CHAIN LOGISTICS LTD | | | SCAC4 |
| 17 | SPCH | Spolek pro chemickou a hutní výrobu, akciová společnost | | CZ | VKM |
| 18 | SPCI | SPECIAL COMMODITIES INC | | | SCAC4 |
| 19 | SPCJ | SPECIAL DISTRIBUTION CALIFORNIA LLC | | | SCAC4 |
| 20 | SPCL | SPECIALIZED TRANSPORT SERVICE | | | SCAC4 |
| 21 | SPCM | SPENCER COMPANIES INCORPORATED | | | SCAC4 |
| 22 | SPCN | SEPSA CUSTODIA DE VALORES SA DE CV | | | SCAC4 |
| 23 | SPCO | SHOPCAM INC | | | SCAC4 |
| 24 | SPCR | SUPERIOR CARRIERS INC | | | SCAC4 |
| 25 | SPCT | SPENCER TRANSPORTATION | | | SCAC4 |
| 26 | SPCU | PACIFIC CONTAINER LEASE PTY LIMITED | | | PWRC |
| 27 | SPCU | Spacific Container Lease Pty | | | RSRV |
| 28 | SPCU | SHANGHAI POINT CONTAINER LEASING CO | | | SCAC4 |
| 29 | SPCV | SUPPLY CHAIN SOLUTIONS LLC | | | SCAC4 |
| 30 | SPCW | SUPERSONIC TRANSPORT LTD | | | SCAC4 |
| 31 | SPCX | Superior Packing Co. | 7/1932 | | NAKINA |
| 32 | SPCX | Fruit Growers Express Co. | 7/1937-4/1938 | | NAKINA |
| 33 | SPCX | E.H. Saunders | 1/1945 (not listed) | | NAKINA |
| 34 | SPCX | Saunders Petroleum Co. | 1/1950 | | NAKINA |
| 35 | SPCX | Saskatchewan Power Corp. | added 7/1978; 1/1980; eliminated 10/1982 | | NAKINA |
| 36 | SPCX | SP Construction Services | added 1/1997; eliminated 4/1998 | | NAKINA |
| 37 | SPCX | Qwest Communications Corp. | added 4/1998; eliminated 7/1998; 7/2000-7/2005 (not listed) | | NAKINA |
| 38 | SPCX | Superior Packing Co. (National Car Co.) | Apr-38 | | NRHS |
| 39 | SPCX | Saskatchewan Power Corp. | added 7/78; 1/80; eliminated 10/82 | | NRHS |
| 40 | SPCX | SP Construction Services | added 1/97; eliminated 4/98 | | NRHS |
| 41 | SPCX | Qwest Communications Corp. | added 4/98; eliminated 7/98; 7/2000 | | NRHS |
| 42 | SPCX | *SUPERIOR PACXKING CO. (FRUIT GROWERS EXPRESS CO.) | | | PWRC |
| 43 | SPCX | *SAUNDERS PETROLEUM CO. [E. H. SAUNDERS] | | | PWRC |
| 44 | SPCX | *SASKATCHEWAN POWER CORP. | | | PWRC |
| 45 | SPCX | *SPRINGERVILLE & CORONADO RAILROAD LINES | | | PWRC |
| 46 | SPCX | *QWEST COMMUNICATIONS CORPORATION [SP CONSTRUCTION SERVICES] | | | PWRC |
| 47 | SPCX | Saskatchewan Power Corporation | | | RSRV |
| 48 | SPCY | SPECIALTY TRUCKING | | | SCAC4 |
| 49 | SPCZ | SCOTT PAPER COMPANY | | | PWRC |
