| 1 | AMT | American Trans Air, Inc. | IATA: TZ, Callsign: AmTran, IATA Prefix: 366, Name changed to ATA Airlines, Inc. d/b/a ATA w.e.f. 19 March 2003. IATA Designator changed from 3T | USA | AVCODES |
| 2 | AMT | ATA Airlines, Inc. d/b/a ATA | IATA: TZ, Callsign: AmTran, IATA Prefix: 366, Ceased Operations on 02 April 2008. Name changed from American Trans Air, Inc. w.e.f. 19 March 2003. | USA | AVCODES |
| 3 | AMT | American Trans Air, Inc. | IATA: 3T, Callsign: AmTran, IATA Designator changed to TZ | USA | AVCODES |
| 4 | AMT | Amazon Sky S.A.C. | Founded in 2006. AOC granted 04 April 2007. | PE | AVCODES |
| 5 | AMT | Air Mountain | Callsign: Air Mountain, | CH | AVCODES |
| 6 | AMT | ATA Airlines | IATA: TZ | | ICAO1 |
| 7 | AMT | *AGENCE MÉTROPOLITAINE DE TRANSPORT | | | PWRC |
| 8 | AMT | *AMTRAK | | | PWRC |
| 9 | AMT | Agence métropolitaine de transport Montréal | | | RSRV |
| 10 | AMT | Association pour le Musée des Transports Urbains, Interurbains et Ruraux | | F | TRAFFIC |
| 11 | AMT | Peter Bosáček - AM Tuning | | SK | VKM |
| 12 | AMTA | AMERICAN TRANSFER & STORAGE INC | | | SCAC3 |
| 13 | AMTA | AMERICA MIDWEST TRANSPORTATION LLC | | | SCAC4 |
| 14 | AMTB | AMERICAN TRUCK LINES INC | | | SCAC3 |
| 15 | AMTC | A M TRANSPORTATION INC | | | SCAC4 |
| 16 | AMTD | ARMOUR TRUCK LINES | | | SCAC3 |
| 17 | AMTD | AMERICAN TRADERS | | | SCAC4 |
| 18 | AMTE | ALL-AMERICAN TRANSFER & STORAGE INC | | | SCAC3 |
| 19 | AMTE | ALL-AMERICAN TRANSFER & STORAGE INC | | | SCAC4 |
| 20 | AMTG | ATLANTIC MARINE TERMINALS | | | SCAC3 |
| 21 | AMTG | AMERICAN TRANSPORT GROUP LLC | | | SCAC4 |
| 22 | AMTG | Azienda Mobilita` e Trasporti | Real: AMT, City: Genova | I | TRAFFIC |
| 23 | AMTH | AMERICAN TRAILER HAUL INC | | | SCAC3 |
| 24 | AMTI | AMERICAN TANK TRANSPORT INC | | | SCAC3 |
| 25 | AMTI | AMERITRANS INC | | | SCAC4 |
| 26 | AMTJ | AMTRUK LEASING INC | | | SCAC3 |
| 27 | AMTK | National R.R. Passenger Corp. NEC | 1/1980-7/2005 | | NAKINA |
| 28 | AMTK | National R.R. Passenger Corp. NEC | 1/80-7/2000 | | NRHS |
| 29 | AMTK | AMTRAK - NATIONAL RAILROAD PASSENGER CORP., NEC | | | PWRC |
| 30 | AMTK | Amtrak (National Railroad Passenger Corporation) | | | RSRV |
| 31 | AMTK | AMTRAK | | | SCAC3 |
| 32 | AMTK | AMTRAK | | | SCAC4 |
| 33 | AMTK | Amtrak | | USA | TRAFFIC |
| 34 | AMTKCA | Amtrak California | | US-CA | TRAFFIC |
| 35 | AMTL | AMERICAN TRAILER REPAIR | | | SCAC3 |
| 36 | AMTL | AMERICAN TRAILER REPAIR | | | SCAC4 |
| 37 | AMTM | ALAMO TRANSPORTATION SERVICES COMPA | | | SCAC4 |
| 38 | AMTM | Agence Metropolitaine de Transport | Real: AMT, City: Montreal | CDN | TRAFFIC |
| 39 | AMTN | A. M. TRANSFER&CRANE SERVICE, INC | | | SCAC3 |
| 40 | AMTN | AUTOMETRICS MOTORSPORTS | | | SCAC4 |
| 41 | AMTO | A & M TRUCKING COMPANY | | | SCAC3 |
| 42 | AMTO | A & M TRANSPORTATION SERVICES INC | | | SCAC4 |
| 43 | AMTP | AMERICAN TRANSPORTATION OF CADES IN | | | SCAC3 |
| 44 | AMTP | ANCHOR MARINE TRANSPORTATION LTD | | | SCAC4 |
| 45 | AMTPI | ARCELOR MITTAL TUBULAR PRODUCTS SA | | RO | VKM |
| 46 | AMTPR | ARCELOR MITTAL TUBULAR PRODUCTS ROMAN SA | | RO | VKM |
| 47 | AMTQ | AMBASSADOR TRUCKING & LEASING CORP | | | SCAC3 |
| 48 | AMTQ | A & M OF TENNESSEE LLC | | | SCAC4 |
| 49 | AMTR | AMERICAN TRANSPORT LINES | | | SCAC3 |
| 50 | AMTR | ARROW MARINE TRANSPORT INC | | | SCAC4 |
| 51 | AMTRAN | Altoona Metro Transit | | USA | TRAFFIC |
| 52 | AMTS | AMERITRANS | | | SCAC3 |
| 53 | AMTS | AMERICA TRANSPORT SYSTEMS INC | | | SCAC4 |
| 54 | AMTT | AMSCO TRANSPORTATION INC | | | SCAC3 |
| 55 | AMTT | AMSCO TRANSPORTATION INC | | | SCAC4 |
| 56 | AMTU | AMT SERVICES SA | | | SCAC3 |
| 57 | AMTV | AMTRANS INC | | | SCAC3 |
| 58 | AMTV | ALPHA MISSION TRANSPORT INC | | | SCAC4 |
| 59 | AMTW | A & M TRANSPORTATION SERVICE | | | SCAC3 |
| 60 | AMTW | A M T TOWING | | | SCAC4 |
| 61 | AMTX | TUCO, Inc. | eliminated 1/2004 | | NAKINA |
| 62 | AMTX | American Refrigerator Transit Co. | added 7/1962; 7/1965-10/1966; eliminated 4/1967; 4/1970 | | NAKINA |
| 63 | AMTX | Mitchell Tank Line | 8/1920 | | NAKINA |
| 64 | AMTX | American Refrigerator Transit Co. | 7/65-10/66; eliminated 4/67; 4/70 | | NRHS |
| 65 | AMTX | *MITCHELL TANK LINE | | | PWRC |
| 66 | AMTX | *AMERICAN REFRIGERATOR TRANSIT CO. | | | PWRC |
| 67 | AMTX | +TUCO, INC. | | | PWRC |
| 68 | AMTX | TUCO INC | | | SCAC4 |
| 69 | AMTY | AMERICAN TRUCK TRANSPORT INC | | | SCAC3 |
| 70 | AMTZ | AMTRAK | | | PWRC |
| 71 | AMTZ | Amtrak (National Railroad Passenger Corporation) | | | RSRV |
| 72 | AMTZ | AMTRAK-NATIONAL RAILROAD PASSENGER | | | SCAC4 |