| 401 | SAM | United States Air Force 89th Airlift Wing | Callsign: Sam, | USA | AVCODES |
| 402 | SAM | SAM Colombia | IATA: MM | | ICAO1 |
| 403 | SAMA | SAMMA | | | SCAC4 |
| 404 | SAMARA | | City: Samara | RUS | TRAFFIC |
| 405 | SAMB | SAMBA EXPRESS INC | | | SCAC4 |
| 406 | SAMC | S&M TRANSPORTATION SYSTEMS | | | SCAC1 |
| 407 | SAMCL | SaM silnice a mosty a.s. | | CZ | VKM |
| 408 | SAMD | SAME DAY INC | | | SCAC4 |
| 409 | SAME | SCOTT AMBULANCE SERVICE | | | PWRC |
| 410 | SAME | SAMCO EPSILON LTD | | | SCAC4 |
| 411 | SAMF | SAMMYS FLOAT SERVICE LTD | | | SCAC4 |
| 412 | SAMH | S AND M XPRESS | | | SCAC4 |
| 413 | SAMI | SAMS TRANSPORT SERVICE INC | | | SCAC4 |
| 414 | SAMJ | SAMS TRUCKING LLC | | | SCAC4 |
| 415 | SAML | SEA AIM MARINE LTD | | | SCAC4 |
| 416 | SAMM | SAMMONS TRUCKING | | | SCAC1 |
| 417 | SAMM | SAMM | | | SCAC4 |
| 418 | SAMN | SUMMIT TOOLS | | | SCAC4 |
| 419 | SAMO | SAMOS STEAMSHIP CO | | | SCAC4 |
| 420 | SAMP | Sampsons | | GB | TRAFFIC |
| 421 | SAMR | SHALOM ALEICHEM MOVING COMPANY INC | | | SCAC4 |
| 422 | SAMS | SAN ANTONIO MERCHANT SHIPPERS LLC ( | | | SCAC4 |
| 423 | SAMTR | San Mateo County Transit District | City: San Mateo | USA | TRAFFIC |
| 424 | SAMU | SAMUDA CHEMICAL COMPLEX LIMITED | | BD | BIC |
| 425 | SAMU | SOUTH AFRICAN MARINE CORP. | | | PWRC |
| 426 | SAMU | South African Marine Corporation | | | RSRV |
| 427 | SAMU | SAFMARINE CONTAINER LINES NV | | | SCAC4 |
| 428 | SAMX | Cargill, Inc. | added 7/1984; 1/1994-7/2005 | | NAKINA |
| 429 | SAMX | Seaboard Allied Milling Dept. of Cargill, Inc. | added 4/1982; eliminated 7/1984 | | NAKINA |
| 430 | SAMX | Seaboard Allied Milling Corp. | added 1/1981; eliminated 4/1982 | | NAKINA |
| 431 | SAMX | Seaboard Allied Milling Corp. | added 1/81; eliminated 4/82 | | NRHS |
| 432 | SAMX | Seaboard Allied Milling Dept. of Cargill, Inc. | added 4/82; eliminated 7/84 | | NRHS |
| 433 | SAMX | Cargill, Inc. | added 7/84; 1/94-7/2000 | | NRHS |
| 434 | SAMX | CARGILL, INC. (SEABOARD ALLIED MILLING DEPT.) | | | PWRC |
| 435 | SAMX | Seaboard Allied Milling Department (Cargill) | | | RSRV |
| 436 | SAMX | CARGILL, INC. | | | SCAC4 |
| 437 | SAMZ | SAHARA MINE | | | PWRC |
| 438 | SAN | Servicios Aereos Nacionales (SAN), S.A. | IATA: WB, Callsign: Aereos, Founded in 1964. Ceased operations in 1999. | EC | AVCODES |
| 439 | SAN | Silvair Sp. z.o.o. | Callsign: Silvar Net, | PL | AVCODES |
| 440 | SAN | Servicios Aereos Nacionales (SAN) | | | ICAO1 |
| 441 | SAN | Sandersville R.R. Co. | 7/1965-1/1994; added 4/1997; 7/2000-7/2005 | | NAKINA |
| 442 | SAN | Sandersville R.R. Co. | 7/65-1/94; added 4/97; 7/2000 | | NRHS |
| 443 | SAN | SANDERSVILLE RAILROAD COMPANY | | | PWRC |
| 444 | SAN | Sandersville Railroad | | | RSRV |
| 445 | SAN | Sandersville Railroad | | USA | TRAFFIC |
| 446 | SANA | SANTA FUEL INC | | | SCAC4 |
| 447 | SANB | SAN-REY CORPORATION | | | SCAC4 |
| 448 | SANCO | Mie Kotsu Co., Ltd. | | J | TRAFFIC |
| 449 | SANDTOFT | Trolleybus Museum at Sandtoft | | GB | TRAFFIC |
| 450 | SANE | SANTA FE TRANSPORTATION COMPANY | | | SCAC4 |
| 451 | SANEX | SANEX S.A. | | RO | VKM |
| 452 | SANF | SANFACON INDUSTRIES INC | | | SCAC4 |
| 453 | SANGI | Sangi Railway | City: San Diego | J | TRAFFIC |
| 454 | SäNJ | Sävsjöström - Nässjö Järnväg | 1914 - 1940 | S | svenska-lok.se |
| 455 | SANM | SANMAR SHIPPING LIMITED | | | SCAC4 |
| 456 | SANO | SANOIL LLC | | | SCAC4 |
| 457 | SANO | SANO-PROPAN GmbH | | DE | VKM |
| 458 | SANOK | MKS Sanok | | PL | TRAFFIC |
| 459 | SANP | SALMA TRANSPORT | | | SCAC4 |
| 460 | SANQ | SANCO TRANSPORTES | | | SCAC4 |
| 461 | SANR | SANDERS, R W TRUCKING INC | | | SCAC4 |
| 462 | SANR | Sanriku Railway | | J | TRAFFIC |
| 463 | SANRE | SANRE, spol. s r.o. | | CZ | VKM |
| 464 | SANS | Sand Springs | Real: SS | USA | TRAFFIC |
| 465 | SANSORIA | Sansori Transportation | | US-NJ | TRAFFIC |
| 466 | SANT | SANDERS TRANSFER, INC | | | SCAC1 |
| 467 | SANU | SAMSKIP HF | | IS | BIC |
| 468 | SANU | SAMBAND ISLENZKRA SAMVINNUFELAG | | | PWRC |
| 469 | SANU | Samband Islenzkra Samvinnufelag | | | RSRV |
| 470 | SANU | SAMSKIP HF | | | SCAC4 |
| 471 | SANW | SMITH&WATERS, INC | | | SCAC1 |
| 472 | SANW | SMITH & WATERS INC | | | SCAC4 |
| 473 | SANX | San Angelo Tank Car Line | added 7/1957; 10/1957-7/2005; eliminated 1/2007 | | NAKINA |
| 474 | SANX | San Angelo Tank Car Line | 10/57-7/2000 | | NRHS |
| 475 | SANX | SAN ANGELO TANK CAR LINE | | | PWRC |
| 476 | SANX | San Angelo Tank Car Line | | | RSRV |
| 477 | SANY | SANYO LOGISTICS CORPORATION | | | SCAC4 |
| 478 | SANZ | SANGAMON INDUSTRIAL | | | PWRC |
| 479 | SAO | Sahel Aviation Service | Callsign: Savser, | RMM | AVCODES |
| 480 | SAO | Sahel Aviation Service | | | ICAO1 |
| 481 | SAOB | STANDARD ASPHALT & OIL COMPANY | | | SCAC4 |
| 482 | SAOC | SANDERS OIL COMPANY | | | SCAC4 |
| 483 | SAOD | SACO LOGISTICS LLC | | | SCAC4 |
| 484 | SAOF | SAMCO GAMMA LTD | | | SCAC4 |
| 485 | SAOI | SAMCO BETA LTD | | | SCAC4 |
| 486 | SAOJ | SANGEO | | | SCAC4 |
| 487 | SAOL | STRAIN ASSOCIATES LTD | | | SCAC4 |
| 488 | SAOM | SAMCO ALPHA LTD | | | SCAC4 |
| 489 | SAOO | SAMSON LOGISTICS LLC | | | SCAC4 |
| 490 | SAOQ | STAVROPEDA E N E | | | SCAC4 |
| 491 | SAOR | SERVICE ANYTIME INC SALEM | | | SCAC4 |
| 492 | SAOS | STRAIGHT SHOT EXPRESS | | | SCAC4 |
| 493 | SAOT | SEASIDE TRANSPORTATION SERVICES INC | | | SCAC4 |
| 494 | SAOU | ARMASUISSE | | CH | BIC |
| 495 | SAOU | DEFENSE PROCUREMENT AGENCY | | | SCAC4 |
| 496 | SAOV | SANDCASTLE OVERSEAS CORP | | | SCAC4 |
| 497 | SAOW | S&M TRANSPORT | | | SCAC1 |
| 498 | SAOW | SERV-ALL OIL CORP | | | SCAC4 |
| 499 | SAOY | ST ANTHONYS TRANSPORT INC | | | SCAC4 |
| 500 | SAP | Sardairline | Callsign: Sardair, | I | AVCODES |
