| 1 | MON | Monarch Airlines Ltd. | IATA: ZB, Callsign: Monarch, IATA Prefix: 974, AOC withdrawn by CAA 02 October 2017. | GB | AVCODES |
| 2 | MON | Monarch Airlines Ltd. | IATA: OM, Callsign: Monarch, IATA designator changed to ZB | GB | AVCODES |
| 3 | MON | Monarch Airlines | IATA: ZB | | ICAO1 |
| 4 | MON | CSX Transportation, Inc. | added 7/1987; 1/1994-7/2005 | | NAKINA |
| 5 | MON | Seaboard System R.R., Inc. | added 1/1983; eliminated 7/1987 | | NAKINA |
| 6 | MON | Louisville and Nashville R.R. Co. | 1/1975-1/1980; eliminated 1/1983 | | NAKINA |
| 7 | MON | Monon R.R. | 10/1957-10/1966 | | NAKINA |
| 8 | MON | Monon R.R. | 10/57-10/66 | | NRHS |
| 9 | MON | Louisville and Nashville R.R. Co. | 1/75-1/80; eliminated 1/83 | | NRHS |
| 10 | MON | Seaboard System R.R., Inc. | added 1/83; eliminated 7/87 | | NRHS |
| 11 | MON | CSX Transportation, Inc. | added 7/87; 1/94-7/2000 | | NRHS |
| 12 | MON | CSX TRANSPORTATION, INC. [SEABOARD; MONON RAILROAD; LOUISVILLE & NASHVILLE RAILROAD CO.,; CHICAGO, INDIANAPOLIS & LOUISVILLE RR ] | | | PWRC |
| 13 | MON | Monon Railroad (CSX Transportation) | | | RSRV |
| 14 | MON | Chicago Indianapolis & Louisville Railroad (Monon) | Real: CIL | USA | TRAFFIC |
| 15 | MONA | MORRISON TRUCKING | | | SCAC4 |
| 16 | MONACELLI | Ditta Monicelli | | I | TRAFFIC |
| 17 | MONB | MARDON STABLES | | | SCAC4 |
| 18 | MONBS | Monroe Bus Service | | USA | TRAFFIC |
| 19 | MONC | MONROE TRANSPORTATION SERVICES | | | SCAC1 |
| 20 | MONC | MONROE TRANSPORTATION SERVICES INCO | | | SCAC4 |
| 21 | MOND | MONSON, R E INC | | | SCAC4 |
| 22 | MONDI | Mondi Stamboliiski | | BG | VKM |
| 23 | MONF | MONFER S.p.A. | | IT | VKM |
| 24 | MONJ | MONSE | | | SCAC4 |
| 25 | MONK | MONKEYS TRUCKING INC | | | SCAC4 |
| 26 | MONL | MONTGOMERY, N L INC | | | SCAC4 |
| 27 | MONM | MONTGOMERY TRANSPORTATION BROKERS I | | | SCAC4 |
| 28 | MONM | Monmouth Bus Lines | | US-NJ | TRAFFIC |
| 29 | MONO | MONTUORI OIL DELIVERY INC | | | SCAC4 |
| 30 | MONP | MONLLOR TRANSPORT CORP | | | SCAC4 |
| 31 | MONQ | MONARCH SHIPPING CO LTD | | | SCAC4 |
| 32 | MONR | MONTANA CENTRAL RAILROAD | | | PWRC |
| 33 | MONS | MONTEGA TRANSFER | | | SCAC4 |
| 34 | MONSA | MONDI ŚWIECIE S.A. | | PL | VKM |
| 35 | MONSEY | Monsey Tours | | USA | TRAFFIC |
| 36 | MONT | MOTION TRANSPORT | | | SCAC4 |
| 37 | MONT | Montour Railroad Company | Real: MTR | USA | TRAFFIC |
| 38 | MONTI | Monti GmbH | | DE | VKM |
| 39 | MONU | BAYER CROPSCIENCE LP | | USA | BIC |
| 40 | MONU | Monsanto | | | RSRV |
| 41 | MONU | MONSANTO CO | | | SCAC4 |
| 42 | MONW | MITSUI O.S.K. LINES, LTD. | | | PWRC |
| 43 | MONW | MONSTER ENTERTAINMENT INC | | | SCAC4 |
| 44 | MONX | Solutia Inc. | added 1/1998; 7/2000-7/2005; eliminated 7/2009 | | NAKINA |
| 45 | MONX | Monsanto Co. | added 7/1964; 7/1965-1/1994; eliminated 1/1998 | | NAKINA |
| 46 | MONX | Monsanto Chemical Co. | 7/1935-4/1961; eliminated 7/1964 | | NAKINA |
| 47 | MONX | Monsanto Chemical Works | 8/1920-7/1932 | | NAKINA |
| 48 | MONX | Monsanto Co. | 4/38-1/52 | | NRHS |
| 49 | MONX | Monsanto Chemical Co. | 10/57-4/61; eliminated 7/64 | | NRHS |
| 50 | MONX | Monsanto Co. | added 7/64; 7/65-1/94; eliminated 1/98 | | NRHS |
| 51 | MONX | Solutia Inc. | added 1/98; 7/2000 | | NRHS |
| 52 | MONX | SOLUTIA INCORPORATED [MONSANTO COMPANY] | | | PWRC |
| 53 | MONX | Monsanto | | | RSRV |
| 54 | MONX | SOLUTIA INC | | | SCAC4 |
| 55 | MONY | MONTGOMERY COUNTY | | | PWRC |
