| 6101 | MNZR | MINZENMAYE | | | SCAC4 |
| 6102 | MNZS | MENZIES EXPRESS SERVICES | | | SCAC4 |
| 6103 | MNZT | MUNOZ TRUCKING INC | | | SCAC4 |
| 6104 | MNZV | MUNOZ TRANSPORT SERVICE | | | SCAC4 |
| 6105 | MO | Calm Air International Ltd. | ICAO: CAV, Callsign: Calm Air, IATA Prefix: 622, Canadian Partner | CDN | AVCODES |
| 6106 | MO | Abu Dhabi Amiri Flight | ICAO: AUH, Callsign: Sultan, Designator OM* recaled by IATA | UAE | AVCODES |
| 6107 | MO | Mohawk Airlines, Inc. | Callsign: Mohawk, | USA | AVCODES |
| 6108 | MO | Airmore Aviation | ICAO: NAA, Callsign: National, | GB | AVCODES |
| 6109 | MO | Cosmos Aviation Services (Private) Ltd. | ICAO: CMK, Callsign: Comos Lanka, | CL | AVCODES |
| 6110 | MO | MOBIL OIL | | | PWRC |
| 6111 | MO | Martigny - Orsieres | | CH | TRAFFIC |
| 6112 | MOA | Air Moravia Czech Charter Airline Ltd. | Callsign: Moras, | CZ | AVCODES |
| 6113 | MOA | Moana Airlines | Callsign: Moana, | NZ | AVCODES |
| 6114 | MOA | Moscow Airlines, JSC | IATA: 7B, Callsign: Moscow Airlines, Ceased operations on 17 January 2011. Name changed from Atlant-Soyuz Airlines w.e.f. 17 September 2010. | RUS | AVCODES |
| 6115 | MOAA | MOTOR CARRIER SERVICE INC | | | SCAC4 |
| 6116 | MOAB | MORGAN TRANSPORT | | | SCAC4 |
| 6117 | MOAC | MACH ONE (1) AIR SERVICES INC | | | SCAC4 |
| 6118 | MOAD | MOORE, A ENTERPRISES INC | | | SCAC4 |
| 6119 | MOAE | MORRIS, A. E | | | SCAC1 |
| 6120 | MOAG | MORGAN, ANGELA INC | | | SCAC4 |
| 6121 | MOAH | MONTERO SHIPPING CORP | | | SCAC4 |
| 6122 | MOAJ | MODLIN, WILLIAM INC | | | SCAC4 |
| 6123 | MOAK | MORRIS SEALCOAT & TRUCKING INC | | | SCAC4 |
| 6124 | MOAL | MONSTER AESTHETICS | | | SCAC4 |
| 6125 | MOAN | MOVIN ON TRANSPORTATION INC | | | SCAC4 |
| 6126 | MOAO | MONTAG OIL INC | | | SCAC4 |
| 6127 | MOAP | MOAPA VALLEY FREIGHT AND PASSENGER SERVICE | | | SCAC1 |
| 6128 | MOAT | MOBILE SERVICE INC | | | SCAC4 |
| 6129 | MOAU | MITSUI O.S.K. LINES LTD | | J | BIC |
| 6130 | MOAU | MITSUI O S K LINES LTD | | | SCAC4 |
| 6131 | MOAV | MACH ONE (1) AIR SERVICE INC (AIR F | | | SCAC4 |
| 6132 | MOAW | MORTIMER & WALLACE INC | | | SCAC4 |
| 6133 | MOB | MITSUI O.S.K. LINES, LTD. | | | PWRC |
| 6134 | MOB | Montreux-Oberland-Bernois | | CH | TRAFFIC |
| 6135 | MOB | Compagnie du Chemins de fer Montreux-Oberland bernois | | CH | VKM |
| 6136 | MOBD | MOBREN LOGISTICS LLC | | | SCAC4 |
| 6137 | MOBE | MOORE BROTHERS TRANSPORT LTD | | | SCAC4 |
| 6138 | MOBI | Mobilis | | PL | TRAFFIC |
| 6139 | MOBJ | MOBRO MARINE INC | | | SCAC4 |
| 6140 | MOBR | MONTY, BRIAN | | | SCAC4 |
| 6141 | MOBS | M-INT AUTO MOTIVE | | | SCAC4 |
| 6142 | MOBT | MAMMOET TRANSPORTATION INC | | | SCAC4 |
| 6143 | MOBU | MOVE INTERMODAL NV | | B | BIC |
| 6144 | MOBU | MUELLE ORIENTAL S A | | | SCAC4 |
| 6145 | MOBUS | MöBus | City: Mönchengladbach | D | TRAFFIC |
| 6146 | MOBV | MID ORIENT BAKERY | | | SCAC4 |
| 6147 | MOBX | Exxon Mobil Corp. | added 7/2000; 7/2000-7/2005 | | NAKINA |
| 6148 | MOBX | Mobil Oil Corp. | added 10/1966; 10/1966-1/1994; eliminated 7/2000 | | NAKINA |
| 6149 | MOBX | Mobil Oil Co., a Division of Socony Mobil Oil Co., Inc. | added 4/1960; eliminated 10/1966 | | NAKINA |
| 6150 | MOBX | Socony Mobil Oil Co., Inc. | 4/61-7/65 | | NRHS |
| 6151 | MOBX | Mobil Oil Co., a Division of Socony Mobil Oil Co., Inc. | eliminated 10/66 | | NRHS |
| 6152 | MOBX | Mobil Oil Corp. | added 10/66; 10/66-1/94; eliminated 7/2000 | | NRHS |
| 6153 | MOBX | Exxon Mobil Corp. | added 7/2000; 7/2000 | | NRHS |
| 6154 | MOBX | EXXON-MOBIL CORP. [MOBIL OIL CORPORATION] | | | PWRC |
| 6155 | MOBX | Mobil Oil Corporation (Exxon-Mobil Corporation) | | | RSRV |
| 6156 | MOBX | EXXON MOBIL CORPORATION | | | SCAC4 |
| 6157 | MOBX | Mobil Oil Corp. | | USA | TRAFFIC |
| 6158 | MOBY | MOBY MARINE CORP | | | SCAC4 |
| 6159 | MOC | Air Monacrch Cargo, S.A. de C.V. | Callsign: Monarch Cargo, | MEX | AVCODES |
| 6160 | MOC | Aero Marat, S.A. de C.V. | Callsign: Aeromarat, | MEX | AVCODES |
| 6161 | MOC | Air Monarch Cargo | | | ICAO1 |
| 6162 | MOC | Missouri Central R.R. Co. | 7/2000-7/2005 | | NAKINA |
| 6163 | MOC | Missouri Central R.R. Co. | Jul-00 | | NRHS |
| 6164 | MOC | MISSOURI CENTRAL RAILROAD | | | PWRC |
| 6165 | MOC | Missouri Central Railroad | | | RSRV |
| 6166 | MOC | MISSOURI CENTRAL RAILROAD COMPANY | | | SCAC4 |
| 6167 | MOCA | MARTIN OIL COMPANY INC | | | SCAC4 |
| 6168 | MOCB | MUTCH OIL CO OF GRAND FORKS INC | | | SCAC4 |
| 6169 | MOCD | MATSON OIL COMPANY INC | | | SCAC4 |
| 6170 | MOCG | MORFINI SPA | | | SCAC4 |
| 6171 | MOCI | MEYERS OIL COMPANY INC | | | SCAC4 |
| 6172 | MOCK | MONSON TRUCK LINE INC | | | SCAC4 |
| 6173 | MOCL | Montgomery City Lines | City: Montgomery, AL | USA | TRAFFIC |
| 6174 | MOCN | MURPHY OIL COMPANY INCORPORATED | | | SCAC4 |
| 6175 | MOCO | MCINTOSH OIL CO INC | | | SCAC4 |
| 6176 | MOCP | MORAN, CHRISTIAN TRANSPORT | | | SCAC4 |
| 6177 | MOCR | MCGILLVREY OIL CO INC | | | SCAC4 |
| 6178 | MOCU | MACS MARITIME CARRIER SHIPPING GMBH & CO | | D | BIC |
| 6179 | MOCU | MACS MARITIME CARRIER SHIPPING GMBH | | | SCAC4 |
| 6180 | MOCX | The Mosaic Co. | added 1/2010 | | NAKINA |
| 6181 | MOCX | Missouri Portland Cement Co. | 1/1941; 4/1947-1/1980; eliminated 10/1984 | | NAKINA |
| 6182 | MOCX | Missouri Portland Cement Co. | 1/52-1/80; eliminated 10/84 | | NRHS |
| 6183 | MOCX | MISSOURI PORTLAND CEMENT COMPANY | | | PWRC |
| 6184 | MOCX | Missouri Portland Cement | | | RSRV |
| 6185 | MOCX | MOSAIC COMPANY, THE | | | SCAC4 |
| 6186 | MOCZ | MURPHY OIL COMPANY | | | PWRC |
| 6187 | MOD | Modiluft Limited | IATA: HT, Callsign: Modiluft, IATA Prefix: 548, Ceased operations in 1996. AOC transferred to Royal Airways t/a SpiceJet | IND | AVCODES |
| 6188 | MOD | Royal Airlines Limited | IATA: 0S, Callsign: Modiluft, Name changed to Royal Airlines Limited d/b/a Spice Jet | IND | AVCODES |
| 6189 | MOD | Royal Airlines Limited d/b/a Spice Jet | IATA: 0S, Callsign: Modiluft, Name changed from Royal Airlines Limited. IATA designator changed to SG. | IND | AVCODES |
| 6190 | MOD | Royal Airlines Limited d/b/a Spice Jet | IATA: SG, Callsign: Modiluft, ICAO designator changed to SEJ. ICAO callsign changed to Spicejet. Name changed from Royal Airlines Limited. IATA designator changed from 0S. | IND | AVCODES |
| 6191 | MOD | Aeroclube de Coimbra | Callsign: Mondego, | P | AVCODES |
| 6192 | MOD | Missouri Pacific System | eliminated 10/1981; eliminated 5/1983 | | NAKINA |
| 6193 | MOD | Missouri Pacific Railroad Co. | added 1/1977; 1/1980 | | NAKINA |
| 6194 | MOD | Texas and Pacific Railway Co. | 1/1975; eliminated 1/1977 | | NAKINA |
| 6195 | MOD | Texas and Pacific Railway Co. | 1/75; eliminated 1/77 | | NRHS |
| 6196 | MOD | Missouri Pacific Railroad Co. | added 1/77; 1/80 | | NRHS |
| 6197 | MOD | Missouri Pacific System | eliminated 10/81; eliminated 5/83 | | NRHS |
| 6198 | MOD | UNION PACIFIC [MISSOURI PACIFIC SYSTEM; TEXAS & PACIFIC RWY. CO.] | | | PWRC |
| 6199 | MOD | Missouri Pacific Railroad | | | RSRV |
| 6200 | MODE | MODESTI BROS | | | SCAC1 |
