| 15301 | AUMS | AUTOMOBILE SHIPPERS, INCORPORATED | | | SCAC3 |
| 15302 | AUMT | AUTOMOTIVE COMPONENT CARRIER LLC | | | SCAC4 |
| 15303 | AUMV | AUTOMOTIVE CONVEYING CO OF NEW JERS | | | SCAC3 |
| 15304 | AUN | Aviones Unidos, S.A. de C.V. | Callsign: Aviones Unidos, | MEX | AVCODES |
| 15305 | AUN | Common Sky A & N Luftfahrt GmbH | Callsign: Common Sky, | D | AVCODES |
| 15306 | AUN | Aviones Unidos | | | ICAO1 |
| 15307 | AUNA | AUSTIN NORTH AMERICAN | | | SCAC3 |
| 15308 | AUNC | AUTHENTIC TOURS INC | | | SCAC3 |
| 15309 | AUND | ASTEN DISTRIBUTION | | | SCAC3 |
| 15310 | AUNI | A A A UNIVERSAL INTERNATIONAL AUTO | | | SCAC3 |
| 15311 | AUNK | AURORA TANKERS INTERNATIONAL LIMITE | | | SCAC4 |
| 15312 | AUNL | ARUTRANS LLC | | | SCAC4 |
| 15313 | AUNM | AUSTIN MOVERS | | | SCAC3 |
| 15314 | AUNO | AUTOTRANSPORTES UNION | | | SCAC4 |
| 15315 | AUNP | AUTOCON MOTORSPORTS | | | SCAC4 |
| 15316 | AUNR | ASTROCIELO NEPTUNEA ARMADORA SA | | | SCAC3 |
| 15317 | AUNU | ADVANCE INTERNATIONAL TRANSPORT | | | SCAC4 |
| 15318 | AUNV | AURORA NAVIGATION S A PAMANA | | | SCAC3 |
| 15319 | AUNW | Austin R.R. (Austin & Northwestern R.R. Co.) | added 1/1987; 1/1994 (not listed); eliminated 7/1996 | | NAKINA |
| 15320 | AUNW | Austin R.R. (Austin & Northwestern R.R. Co.) | added 1/87; 1/94; eliminated 7/96 | | NRHS |
| 15321 | AUNW | AUSTIN RAILROAD CO., INC. D/B/A AUSTIN & NORTHWESTERN | | | PWRC |
| 15322 | AUNW | Austin and Northwestern Railroad | | | RSRV |
| 15323 | AUNW | AUSTIN & NORTHWESTERN RAILROAD CO | | | SCAC3 |
| 15324 | AUO | Empresa (Aero Uruguay), S.A. | IATA: UG, Callsign: Uniform Oscar, Founded in 1977. Ceased operations in 2005. Designator recalled by IATA | ROU | AVCODES |
| 15325 | AUO | Empresa (Aero Uruguay), S.A. | | | ICAO1 |
| 15326 | AUOD | AUTOCON OF DETROIT INC | | | SCAC3 |
| 15327 | AUOF | AUTO TRANSPORT AMERICA INC (FREIGHT | | | SCAC3 |
| 15328 | AUOI | AUTOSPORT INC | | | SCAC4 |
| 15329 | AUOK | AUTOSTACK INC | | | SCAC3 |
| 15330 | AUOL | AUTORE OIL & PROPANE | | | SCAC4 |
| 15331 | AUOM | AUTOMAR INC | | | SCAC3 |
| 15332 | AUOM | AUTOMAR INC | | | SCAC4 |
| 15333 | AUON | AUTOTECNIA | | | SCAC4 |
| 15334 | AUOR | AUTO RAIL SYSTEMS INC | | | SCAC3 |
| 15335 | AUOT | AUTO TRANSPORTERS I INC | | | SCAC3 |
| 15336 | AUOV | AUTOTRANSPORTES REFRIGERADOS LA PAL | | | SCAC4 |
| 15337 | AUP | Avia Business Group | | RUS | AVCODES |
| 15338 | AUP | Avia Business Group | | | ICAO1 |
| 15339 | AUPA | AUTO PARTES EL ARABE | | | SCAC4 |
| 15340 | AUPC | AUTO PLACEMENT CENTER INC | | | SCAC3 |
| 15341 | AUPD | ASSURED PACKAGE DELIVERY INC | | | SCAC3 |
| 15342 | AUPE | AUTO PARTS EXPRESS INC | | | SCAC3 |
| 15343 | AUPI | AUTO PORT INC | | | SCAC3 |
| 15344 | AUPI | AUSTIN PRODUCTIONS INC | | | SCAC4 |
| 15345 | AUPL | AUTOPORT LIMITED | | | SCAC3 |
| 15346 | AUPO | AUSTINS PACKAGE DELIVERY | | | SCAC3 |
| 15347 | AUPP | ACCU-TEMP TRANSPORTATION INC | | | SCAC3 |
| 15348 | AUPT | AUTO-PORT INC | | | SCAC3 |
| 15349 | AUPX | Austin Powder Co. | 7/1937-4/1970; eliminated 1/1975 | | NAKINA |
| 15350 | AUPX | Austin Powder Co. | 4/38-4/70; eliminated 1/75 | | NRHS |
| 15351 | AUPX | AUSTIN POWDER CO. | | | PWRC |
| 15352 | AUPZ | AUTO PLANT | | | PWRC |
| 15353 | AUQF | AUTO FREIGHT LINK NATIONAL CITY CA | | | SCAC3 |
| 15354 | AUQM | AFAQ UMM QASER (MARINE SERVICES CO) | | | SCAC4 |
| 15355 | AUR | Aurigny Air Services Limited | IATA: GR, Callsign: Ayline, IATA Prefix: 924, | GBG | AVCODES |
| 15356 | AUR | Aurigny Air Services | IATA: GR | | ICAO1 |
| 15357 | AURA | AURORA TRANSPORT INC | | | SCAC3 |
| 15358 | AURA | AURORA TRANSPORT INC | | | SCAC4 |
| 15359 | AURB | AURORA BOREALIS COMPANIA ARMADORA | | | SCAC3 |
| 15360 | AURC | AUTO-RIDE CAB COMPANY | | | SCAC3 |
| 15361 | AURE | ABLE COURIER | | | SCAC3 |
| 15362 | AURE | AUTORETRO | | | SCAC4 |
| 15363 | AURG | AURORA SHIPPING CORPORATION | | | SCAC4 |
| 15364 | AURI | AURORA TOWING INC | | | SCAC3 |
| 15365 | AURK | AURORA TRUCKING INC | | | SCAC3 |
| 15366 | AURM | AURORA MOVING AND STORAGE CO, INC | | | SCAC3 |
| 15367 | AURN | ACCUTRAN INC | | | SCAC4 |
| 15368 | AURP | AURORA PACIFIC TRUCKING | | | SCAC3 |
| 15369 | AURT | AUGUST, RON TRUCKING INC | | | SCAC3 |
| 15370 | AURT | AURIGA SHIPPING CO LTD | | | SCAC4 |
| 15371 | AURU | AURORA CONTAINERS LIMITED | | HK | BIC |
| 15372 | AURV | A LIMOUSINE SERVICE | | | SCAC3 |
| 15373 | AURZ | Aurizon | | AUS | TRAFFIC |
| 15374 | AUS | Aus-Air | | AUS | AVCODES |
| 15375 | AUS | Australian Airlines | IATA: TN, Callsign: Australina, Merged into Qantas in April 1994. | AUS | AVCODES |
| 15376 | AUS | Australian International Airlines | | AUS | AVCODES |
| 15377 | AUS | Aus-Air | IATA: NO | | ICAO1 |
| 15378 | AUS | Augusta Southern R.R. | 8/1920-7/1923 | | NAKINA |
| 15379 | AUS | Augusta & Summerville R.R. Co. | 1/1975-1/1980 | | NAKINA |
| 15380 | AUS | Augusta Southern R.R. | 23-Jul | | NRHS |
| 15381 | AUS | Augusta & Summerville R.R. Co. | 1/75-1/80 | | NRHS |
| 15382 | AUS | *AUGUSTA SOUTHERN RAILROAD | | | PWRC |
| 15383 | AUS | *AUGUSTA & SOMMERVILLE RAILROAD | | | PWRC |
| 15384 | AUS | Augusta Southern Railroad | | | RSRV |
| 15385 | AUS | Augusta and Summerville Railroad | | | RSRV |
| 15386 | AUS | Australia | | AUS | TRAFFIC |
| 15387 | AUSA | AUSTIN, ALAN | | | SCAC3 |
| 15388 | AUSA | Australian Army | | AUS | TRAFFIC |
| 15389 | AUSB | AUSTIN TRUCKING COMPANY INC | | | SCAC3 |
| 15390 | AUSC | AUBURN SHIPPING CORPORATION | | | SCAC3 |
| 15391 | AUSC | AUBURN SHIPPING CORPORATION | | | SCAC4 |
| 15392 | AUSD | AUSTAD, CARL J & SON INC | | | SCAC3 |
| 15393 | AUSE | AUTO CLUB OF SOUTHERN PENNSYLVANIA | | | SCAC3 |
| 15394 | AUSF | AUSTINS FINEST MOVING & STORAGE | | | SCAC3 |
| 15395 | AUSG | AUTOCARS SARTIGAN INC | | | SCAC3 |
| 15396 | AUSH | AAA-U S INTERNATIONAL TRANSPORTATIO | | | SCAC3 |
| 15397 | AUSI | ACTIVE USA INC | | | SCAC4 |
| 15398 | AUSJ | AUSTIN TRUCKING | | | SCAC4 |
| 15399 | AUSK | AUSTIN TRUCKING | | | SCAC3 |
| 15400 | AUSM | AUSTIN, FRED TRUCKING INC | | | SCAC3 |
