| 4001 | SGL | Schienen Güter Logistik GmbH | | DE | VKM |
| 4002 | SGLB | STARLITE LOGISTICS INC | | | SCAC4 |
| 4003 | SGLC | STARGATE LOGISTICS LTD | | | SCAC4 |
| 4004 | SGLD | SOUTH GOLD CORP | | | SCAC4 |
| 4005 | SGLH | SUN CITY LOGISTICS | | | SCAC4 |
| 4006 | SGLI | S & G LEASING INC | | | SCAC4 |
| 4007 | SGLK | SALEM GLOBAL LOGISTICS INC | | | SCAC4 |
| 4008 | SGLL | SEAGULL SERVICES SA PANAMA | | | SCAC4 |
| 4009 | SGLM | SERVICE G L PARADIS INC | | | SCAC4 |
| 4010 | SGLO | SINGLE GROUP LOGISTICS CORP | | | SCAC4 |
| 4011 | SGLQ | STEGALL, T G TRUCKING COMPANY INC | | | SCAC4 |
| 4012 | SGLR | Seminole Gulf Ry. L.P. | added 4/1988; 1/1994-7/2005; eliminated 7/2008; added 4/2009 | | NAKINA |
| 4013 | SGLR | Seminole Gulf Ry. L.P. | added 4/88; 1/94-7/2000 | | NRHS |
| 4014 | SGLR | SEMINOLE GULF RAILWAY | | | PWRC |
| 4015 | SGLR | Seminole Gulf Railway | | | RSRV |
| 4016 | SGLR | SEMINOLE GULF RAILWAY L P | | | SCAC4 |
| 4017 | SGLR | Seminole Gulf | | USA | TRAFFIC |
| 4018 | SGLU | SICGIL INDUSTRIAL GASES LTD | | IND | BIC |
| 4019 | SGLV | SGLS INC | | | SCAC4 |
| 4020 | SGLW | SOUTHERN GLOBAL LOGISTICS LLC | | | SCAC4 |
| 4021 | SGLY | STEAGALL OIL CO INC | | | SCAC4 |
| 4022 | SGLZ | GENERAL ELECTRIC | | | PWRC |
| 4023 | SGM | Sky Aircraft Service | Callsign: Sigma, | NL | AVCODES |
| 4024 | SGM | Sky Aircraft Service | | | ICAO1 |
| 4025 | SGMA | SMG TRANSPORT LLC | | | SCAC4 |
| 4026 | SGMC | STECHSCHULTE GAS AND OIL COMPANY IN | | | SCAC4 |
| 4027 | SGMD | SGM INC | | | SCAC4 |
| 4028 | SGMF | SGT TWO THOUSAND (2000) MOTOR FREIG | | | SCAC4 |
| 4029 | SGMG | SINGLETON MOVING & STORAGE INC | | | SCAC4 |
| 4030 | SGMH | SGM & SA | | | SCAC4 |
| 4031 | SGMK | STRIGHT-MACKAY LTD | | | SCAC4 |
| 4032 | SGML | SLADES CARTAGE LIMITED | | | SCAC4 |
| 4033 | SGMQ | SUMAS GRO MEDIA | | | SCAC4 |
| 4034 | SGMS | STERLING MOTOR LINES INC | | | SCAC4 |
| 4035 | SGMT | SEA GLOBE MANAGEMENT & TRADING INC | | | SCAC4 |
| 4036 | SGMU | SIGMA DENIZCILIK KONT.VE.LOJ.SANT.TIC. | | TR | BIC |
| 4037 | SGMU | SEATRAIN GITMO, INC. | | | SCAC4 |
| 4038 | SGMV | SIMMINGER TRUCKING | | | SCAC4 |
| 4039 | SGMW | SEAGULF MARINE IND INC | | | SCAC4 |
| 4040 | SGMY | STERLING MATERIAL HANDLING | | | SCAC4 |
| 4041 | SGN | Imperial Air Charter Ltd. | Callsign: Sovereign, | GB | AVCODES |
| 4042 | SGN | Siam General Aviation Company Limited d/b/a Nok Mini Airlines | IATA: 5E, Callsign: Siam, Ceased Operations during 2014. | T | AVCODES |
| 4043 | SGN | Siam GA | | | ICAO1 |
| 4044 | SGND | SMOKING GUN CATTLE CARRIERS LTD | | | SCAC4 |
| 4045 | SGNF | SIGNAL TRUCKING LP | | | SCAC4 |
| 4046 | SGNG | SIGNATURE | | | SCAC4 |
| 4047 | SGNH | SANGAMON TRANSPORTATION GROUP | | | SCAC4 |
| 4048 | SGNI | SGS TRANSPORT INC | | | SCAC4 |
| 4049 | SGNJ | SYGMA NETWORK, THE | | | SCAC4 |
| 4050 | SGNK | SLAGNEB | | | SCAC4 |
| 4051 | SGNM | SARGEANT MARINE INC | | | SCAC4 |
| 4052 | SGNN | SMITH, GARY N TRUCKING INC | | | SCAC4 |
| 4053 | SGNO | SARGENTO TRANPORTATION LLC | | | SCAC4 |
| 4054 | SGNP | SIGNATURE TRANSPORT, INC | | | SCAC1 |
| 4055 | SGNP | SEGUIN TRANSPORT | | | SCAC4 |
| 4056 | SGNS | STURGEON & SON INC | | | SCAC4 |
| 4057 | SGNU | SOGIN SPA | | I | BIC |
| 4058 | SGNU | SOGIN SPA | | | SCAC4 |
| 4059 | SGNV | SEATRADE GROUP N V | | | SCAC4 |
| 4060 | SGNW | SCHILLING INC | | | SCAC4 |
| 4061 | SGNY | SEA GATE NAVIGATION LTD | | | SCAC4 |
| 4062 | SGO | Space Cargo, Inc. | Callsign: Space Cargo, | GQ | AVCODES |
| 4063 | SGO | VVB Aviation Malta | IATA: IV, Callsign: Maiden, Name changed to Cardiff Aviation Malta Ltd. | M | AVCODES |
| 4064 | SGO | Cardiff Aviation Malta Ltd. | IATA: IV, Callsign: Maiden, Ceased operations in 2017. Name changed from VVB Aviation Malta | M | AVCODES |
| 4065 | SGO | Admiral Beverage Corporation | Callsign: Speedgoat, | USA | AVCODES |
| 4066 | SGOC | ST LOGISTICS LLC | | | SCAC4 |
| 4067 | SGOG | SHOTGUNS AND STEREOS CLOTHING | | | SCAC4 |
| 4068 | SGOH | ST ONGES CUSTOM SPREADING & HAULING | | | SCAC4 |
| 4069 | SGOK | Stojlenskij | Opencast mining "Stojlenskij", Stary Oskol, Belgorod area in Russia | RUS | TRAFFIC |
| 4070 | SGOL | SHANKS, GLENN OIL CO INC | | | SCAC4 |
| 4071 | SGON | STRONG TRUCKING | | | SCAC4 |
| 4072 | SGOO | SHUGOO TRUCKING | | | SCAC4 |
| 4073 | SGOQ | SE LOGISTICS INC | | | SCAC4 |
| 4074 | SGOR | SUNGLO TRANSPORT INC | | | SCAC4 |
| 4075 | SGOV | SOUTHERN CARGO SERVICES (DIV SOUTHE | | | SCAC4 |
| 4076 | SGOW | SINSUNG LOGISTICS CO LTD | | | SCAC4 |
| 4077 | SGP | Sagolair Transportes Ejecutivos S.L. | Callsign: Sagolair, | E | AVCODES |
| 4078 | SGP | Sagolair Transportes Ejecutivos | | | ICAO1 |
| 4079 | SGPC | SARGENT PIPE CO INC | | | SCAC4 |
| 4080 | SGPE | SHRIGLEY, PERRY TRUCKING LTD | | | SCAC4 |
| 4081 | SGPF | SOHAL GROUP INC | | | SCAC4 |
| 4082 | SGPG | SOSSEH GROUP LLC | | | SCAC4 |
| 4083 | SGPL | SUPERIOR LOGISTICS SERVICES INC | | | SCAC4 |
| 4084 | SGPM | SONNTAG PETROLEUM TRANSPORT INC | | | SCAC4 |
| 4085 | SGPN | SUGAR PLAY ENTERPRISES LIMITED | | | SCAC4 |
| 4086 | SGPO | STERLING TRANSPORT | | | SCAC4 |
| 4087 | SGPQ | STRAIGHT POINT LINE INC | | | SCAC4 |
| 4088 | SGPS | SERGI, PAT | | | SCAC4 |
| 4089 | SGPU | SSB CRYOGENIC EQUIPMENT PTE LTD | | SGP | BIC |
| 4090 | SGPV | SEAGOLD (PRIVATE) LIMITED | | | SCAC4 |
| 4091 | SGPX | Shellabarger Grain Products Co. | 7/1935-7/1937 | | NAKINA |
| 4092 | SGPX | *SHELLABARGER GRAIN PRODUCTS CO. | | | PWRC |
| 4093 | SGPX | *SKIP GIBBS | | | PWRC |
| 4094 | SGPY | SFI GROUP LTD | | | SCAC4 |
| 4095 | SGQ | SaudiGulf Airlines | IATA: 6S, Callsign: Saudi Gold, Designator 6S recalled by IATA.Commence domestic operations on 29 October 2016. Wholly owned by Abdul Hadi Al Qahtani Group of Companies. | SA | AVCODES |
| 4096 | SGQ | SaudiGulf Airlines | Callsign: Saudi Gold, Designator 6S recalled by IATA.Commence domestic operations on 29 October 2016. Wholly owned by Abdul Hadi Al Qahtani Group of Companies. | SA | AVCODES |
| 4097 | SGQB | S G T TWO THOUSAND (2000) INC | | | SCAC4 |
| 4098 | SGQC | STAGE CALL CORPORATION | | | SCAC4 |
| 4099 | SGQD | SRP ENGINEERING LTD | | | SCAC4 |
| 4100 | SGQI | SULCO LOGISTICS INC | | | SCAC4 |
