| 10301 | SSVC | SISTEMAS Y SERVICIOS DE COMUNICACIO | | | SCAC4 |
| 10302 | SSVD | SSG VENTURES INC | | | SCAC4 |
| 10303 | SSVE | SEA SUPPORT VENTURES LLC | | | SCAC4 |
| 10304 | SSVG | SCHENIAN, STEVEN R TRUCKING INC | | | SCAC4 |
| 10305 | SSVH | SHUTTLE SERVICE INC | | | SCAC4 |
| 10306 | SSVK | SALES AND SALVAGE LLC | | | SCAC4 |
| 10307 | SSVL | SSTL LLC | | | SCAC4 |
| 10308 | SSVM | SUPER SERVICE MOTOR FREIGHT, INC | | | SCAC1 |
| 10309 | SSVM | SUPER SERVICE MOTOR FREIGHT INC | | | SCAC4 |
| 10310 | SSVO | STAN'S TRUCKING LLC | | | SCAC4 |
| 10311 | SSVP | SHANGHAI SALVAGE COMPANY | | | SCAC4 |
| 10312 | SSVR | SUN STATE VAN SERVICES INC | | | SCAC4 |
| 10313 | SSVT | SEASERVICE TA | | | SCAC4 |
| 10314 | SSVX | Spray Services, Inc. | added 7/1977; eliminated 1/1979 | | NAKINA |
| 10315 | SSVX | SSI Industries, Inc. | added 1/1979; 1/1980; eliminated 5/1983 | | NAKINA |
| 10316 | SSVX | SSI Industries, Inc. (MofW cars) | 1/1994-7/2005 | | NAKINA |
| 10317 | SSVX | Spray Services, Inc. | added 7/77; eliminated 1/79 | | NRHS |
| 10318 | SSVX | SSI Industries, Inc. | added 1/79; 1/80; eliminated 5/83 | | NRHS |
| 10319 | SSVX | SSI Industries, Inc. (MofW cars) | 1/94-7/2000 | | NRHS |
| 10320 | SSVX | SSI INDUSTRIES, MOW CARS [SPRAY SERVICES, INC.] | | | PWRC |
| 10321 | SSVX | SSI Industries | | | RSRV |
| 10322 | SSVY | S & S DELIVERY SERVICE | | | SCAC4 |
| 10323 | SSW | Streamline Aviation Ltd. | Callsign: Streamline, ICAO designator changed from STM | GB | AVCODES |
| 10324 | SSW | Streamline Aviation | | | ICAO1 |
| 10325 | SSW | St. Louis Southwestern Ry. Co. (Cotton Belt Route) | 8/1920-7/1936 | | NAKINA |
| 10326 | SSW | St. Louis Southwestern Ry. Co. of Texas (Cotton Belt Route) | 8/1920-7/1936 | | NAKINA |
| 10327 | SSW | St. Louis Southwestern Ry. Co. | 4/1938-1/1994; eliminated 10/1997 | | NAKINA |
| 10328 | SSW | Union Pacific R.R. Co. | added 10/1997; 7/2000-7/2005 | | NAKINA |
| 10329 | SSW | Cotton Belt Route | 23-Jul | | NRHS |
| 10330 | SSW | St. Louis Southwestern Ry. Co. | 4/38-1/94; eliminated 10/97 | | NRHS |
| 10331 | SSW | Union Pacific R.R. Co. | added 10/97; 7/2000 | | NRHS |
| 10332 | SSW | UNION PACIFIC RR [SOUTHERN PACIFIC; ST. LOUIS SOUTHWESTERN (COTTON BELT)] | | | PWRC |
| 10333 | SSW | St. Louis Southwestern Railway (Union Pacific Railroad) | | | RSRV |
| 10334 | SSW | St. Louis Southwestern Railway (Cotton Belt) | | USA | TRAFFIC |
| 10335 | SSWB | STERICYCLE SPECIALTY WASTE SOLUTION | | | SCAC4 |
| 10336 | SSWC | SOLUTIONS THRU SOFTWARE LTD | | | SCAC4 |
| 10337 | SSWE | SANTA SWEETS INC | | | SCAC4 |
| 10338 | SSWF | SSW FREIGHT LLC | | | SCAC4 |
| 10339 | SSWI | SARDO & SONS WAREHOUSING INC | | | SCAC4 |
| 10340 | SSWL | SHANHOLTZ, S W LLC | | | SCAC4 |
| 10341 | SSWM | SELECT SAWMILL COMPANY | | | SCAC4 |
| 10342 | SSWN | Southern Pacific Chicago St. Louis Connection | added 1/1990 | | NAKINA |
| 10343 | SSWN | SPCSL, Corp. | 1/1994; eliminated 7/1997 | | NAKINA |
| 10344 | SSWN | Union Pacific R.R. Co. | added 7/1997; 7/2000-7/2005 | | NAKINA |
| 10345 | SSWN | Southern Pacific Chicago St. Louis Connection | added 1/90 | | NRHS |
| 10346 | SSWN | SPCSL, Corp. | 1/94; eliminated 7/97 | | NRHS |
| 10347 | SSWN | Union Pacific R.R. Co. | added 7/97; 7/2000 | | NRHS |
| 10348 | SSWN | UNION PACIFIC RAILROAD COMPANY [SOUTHERN PACIFIC, CHICAGO, ST.LOUIS CORP.] | | | PWRC |
| 10349 | SSWN | St. Louis Southwestern Railway (Union Pacific Railroad) | | | RSRV |
| 10350 | SSWO | SS TEWASHO LLC | | | SCAC4 |
| 10351 | SSWP | SWOOPE SR, WILLIAM N TRUCKING LLC | | | SCAC4 |
| 10352 | SSWQ | SIMS WORLDWIDE INC | | | SCAC4 |
| 10353 | SSWR | SELS SWIFT SERVICE INC | | | SCAC4 |
| 10354 | SSWS | S & S TOW/TRUCKING SERVICE | | | SCAC4 |
| 10355 | SSX | Lynx Aviation, Inc. | IATA: L3, Callsign: Shasta, Subsidiary of Republic Airways Holdings, Inc. ICAO designator changed from SHA | USA | AVCODES |
| 10356 | SSX | Belgium Exel | Callsign: Sunshine Exel, | B | AVCODES |
| 10357 | SSX | Southern States Phosphate and Fertilizer Co. | added 1/1953; eliminated 1/1954 | | NAKINA |
| 10358 | SSX | Southern States Phosphate and Fertilizer Co. | added 1/53 | | NRHS |
| 10359 | SSX | SOUTHERN STATES PHOSPHATE & FERTILIZER CO. | | | PWRC |
| 10360 | SSXB | STS TRANSPORTATION LLC | | | SCAC4 |
| 10361 | SSXD | S & S EXPRESS LTD | | | SCAC4 |
| 10362 | SSXK | SOUTH SIDE TRANSPORTATION INC | | | SCAC4 |
| 10363 | SSXL | SOMAL STAR TRANSPORT INC | | | SCAC4 |
| 10364 | SSXM | SOMERSET TRANSPORT LLC | | | SCAC4 |
| 10365 | SSXN | SAM SUNG EXPRESS INC | | | SCAC4 |
| 10366 | SSXQ | SHUTTLE SERVICE XPRESS | | | SCAC4 |
| 10367 | SSXR | STRAIGHT SHOT EXPRESS | | | SCAC4 |
| 10368 | SSXS | STRAIGHT SHOT EXPRESS | | | SCAC4 |
| 10369 | SSXU | SAMSON SERVICE LLC | | RUS | BIC |
| 10370 | SSXV | S & S TRANSPORTATION SERVICES | | | SCAC4 |
| 10371 | SSXW | S & S EXPRESS | | | SCAC4 |
| 10372 | SSXY | SUMMIT 66 OIL CO INC | | | SCAC4 |
| 10373 | SSY | Excel Aviation Limited | Merged with Sabre Airways Ltd as Excel Airways ICAO designator XLA | GB | AVCODES |
| 10374 | SSY | Sky Aviation Ltd. | Callsign: Sierra Sky, | WAL | AVCODES |
| 10375 | SSY | Sky Aviation | | | ICAO1 |
| 10376 | SSYC | SCHNEIDER SPECIALIZED CARRIERS, INC. | | | SCAC1 |
| 10377 | SSYI | SILVER SPRAY SPORTS INC | | | SCAC4 |
| 10378 | SSYR | SASSY TRUCKING LLC | | | SCAC4 |
| 10379 | SSYV | STEELNOR SYSTEMS | | | SCAC4 |
| 10380 | SSZ | Specsavers Aviation Ltd. | Callsign: Specsavers, | GB | AVCODES |
| 10381 | SSZ | Specsavers Aviation | | | ICAO1 |
| 10382 | SSZI | SL SPECIALIZED TRANSPORTATION INC | | | SCAC4 |
| 10383 | SSZN | SIX SEVEN ZERO NINE ZERO FIVE TWO ( | | | SCAC4 |
| 10384 | SSZO | SIX SIX FIVE ZERO SIX EIGHT SIX (66 | | | SCAC4 |
| 10385 | SSZT | SS STAR TRANSPORTATION INC | | | SCAC4 |
| 10386 | ST | Germania Fluggesellschaft mbH | ICAO: GMI, Callsign: Germania, Ceased operations on 05 February 2019. ICAO designator changed from GFG. Founded in 1986. | D | AVCODES |
| 10387 | ST | Yanda Airlines | Designator changed to YE. Formerly Singleton Air Serivces | AUS | AVCODES |
| 10388 | ST | Société de Transports Aériens en Extrême-Orient | | VN | AVCODES |
| 10389 | ST | Western Aircraft, Inc. | ICAO: STT, Callsign: Sawtooth, | USA | AVCODES |
| 10390 | ST | Air Thanlwin Holding Company Limited | ICAO: AYG, Callsign: Royal Bird, Name changed from Yangon Airways Limited in February 2014. IATA Designator changed from YH*. ICAO designator changed to RTL. IATA designator changed from HK* w.e.f. 15 June 2009. | MYA | AVCODES |
| 10391 | ST | Air Thanlwin Holding Company Limited | ICAO: RTL, Callsign: Royal Bird, Name changed from Yangon Airways Limited in February 2014. IATA Designator changed from YH*. ICAO designator changed from AYG. IATA designator changed from HK* w.e.f. 15 June 2009. | MYA | AVCODES |
| 10392 | ST | Springfield Terminal Ry. Co. (Vermont) | 1/1975-1/1980; eliminated 4/1985 | | NAKINA |
| 10393 | ST | Springfield Terminal Ry. Co. (MA) | added 4/1985; eliminated 10/1987 | | NAKINA |
| 10394 | ST | Springfield Terminal Ry. Co. (NH) | added 10/1987 | | NAKINA |
| 10395 | ST | Springfield Terminal Ry. Co. | 1/1994 | | NAKINA |
| 10396 | ST | Springfield Terminal Ry. Co. (NH) | eliminated 10/1997 | | NAKINA |
| 10397 | ST | ST Rail System | 7/2000-7/2005 | | NAKINA |
| 10398 | ST | Springfield Terminal Ry. Co. (Vermont) | 1/75-1/80; eliminated 4/85 | | NRHS |
| 10399 | ST | Springfield Terminal Ry. Co. (MA) | added 4/85; eliminated 10/87 | | NRHS |
| 10400 | ST | Springfield Terminal Ry. Co. (NH) | added 10/87 | | NRHS |
