| 1 | MP | Martinair Holland N.V. | ICAO: MPH, Callsign: Martinair, IATA Prefix: 129, Name changed from Martin's Luchtvervoermaatschappij (Martin's Aircharter Company M.A.C.) N.V | NL | AVCODES |
| 2 | MP | Martin's Luchtvervoermaatschappij (Martin's Aircharter Company M.A.C.) N.V | Name changed to Martinair Holland N.V. | NL | AVCODES |
| 3 | MP | Union Pacific R.R. Co. | added 4/1997; 7/2000-7/2005 | | NAKINA |
| 4 | MP | Missouri Pacific System | 1/1994; eliminated 4/1997 | | NAKINA |
| 5 | MP | Missouri Pacific R.R. Co. | 7/1923-10/1966 & 1/1975-1/1980 | | NAKINA |
| 6 | MP | Missouri Pacific R.R. Co. | 4/38-10/66 & 1/75-1/80 | | NRHS |
| 7 | MP | Missouri Pacific System | 1/94; eliminated 4/97 | | NRHS |
| 8 | MP | Union Pacific R.R. Co. | added 4/97; 7/2000 | | NRHS |
| 9 | MP | UNION PACIFIC [MISSOURI PACIFIC RAILROAD] | | | PWRC |
| 10 | MP | Missouri Pacific Railroad (Union Pacific Railroad) | | | RSRV |
| 11 | MP | MISSOURI PACIFIC RAILROAD COMPANY | | | SCAC4 |
| 12 | MP | Missouri Pacific | | USA | TRAFFIC |
| 13 | MP&N | Mineral Point & Northern Ry. Co. | 7/1923 | | NAKINA |
| 14 | MP&N | MINERAL POINT & NORTHERN RWY. CO. | | | PWRC |
| 15 | MPA | Mid-Pacific Airlines, Inc. | Callsign: Mid Pac, | USA | AVCODES |
| 16 | MPA | Mid-Pacific Airlines | | | ICAO1 |
| 17 | MPA | York Ry. Co. | added 4/2000; 7/2000-7/2005 | | NAKINA |
| 18 | MPA | Maryland & Pennsylvania R.R. Co. | 1/1975-1/1994; eliminated 4/2000 | | NAKINA |
| 19 | MPA | Maryland & Pennsylvania R.R. Co. | 1/75-1/94; eliminated 4/2000 | | NRHS |
| 20 | MPA | York Ry. Co. | added 4/2000; 7/2000 | | NRHS |
| 21 | MPA | YORK RAILWAY CO. [MARYLAND & PENNSYLVANIA RAILROAD] | | | PWRC |
| 22 | MPA | Maryland and Pennsylvania Railroad (York Railway) | | | RSRV |
| 23 | MPA | Maryland & Pennsylvania R.R. Co. | | USA | TRAFFIC |
| 24 | MPAC | MUCCIPAC | | | SCAC4 |
| 25 | MPAD | MARYLAND PORT AUTHORITY | | | PWRC |
| 26 | MPAD | MPA | | | SCAC4 |
| 27 | MPAE | MT PAN ADVENTURE | | | SCAC4 |
| 28 | MPAF | MAINES PAPER AND FOOD SERVICE INC | | | SCAC4 |
| 29 | MPAJ | MODA PARA AUTOS S DE RL DE | | | SCAC4 |
| 30 | MPAK | MASCO PETROLEUM INC | | | SCAC4 |
| 31 | MPAN | MISSION PRODUCE INC | | | SCAC4 |
| 32 | MPAP | M P AGRI-PRODUCTS | | | SCAC4 |
| 33 | MPAQ | MIKES PAINT AND BODY INC | | | SCAC4 |
| 34 | MPAT | MORENO, PATRICIA | | | SCAC4 |
| 35 | MPAU | MITSUBISHI POLYCRYSTALLINE SILICON AM CO | | USA | BIC |
| 36 | MPAV | MANNON EXCAVATING & PAVING CO INC | | | SCAC4 |
| 37 | MPAW | MT PAN AEGIS | | | SCAC4 |
| 38 | MPAX | MITSUBISHI POWER SYSTEMS AMERICAS, INC. | | | PWRC |
| 39 | MPAX | MITSUBISHI POWER SYSTEMS AMERICAS I | | | SCAC4 |
| 40 | MPBA | MANNING, PATRICK | | | SCAC4 |
| 41 | MPBD | MP COMBUSTION PROCESS LTD | | | SCAC4 |
| 42 | MPBI | MOYLE PETROLEUM COMPANY | | | SCAC4 |
| 43 | MPBK | MINIMUM PRICE BOOKS | | | SCAC4 |
| 44 | MPBQ | MARTEN TRANSPORT LTD (DEDICATED DIV | | | SCAC4 |
| 45 | MPBT | MERLIN SHIPPING LLC | | | SCAC4 |
| 46 | MPBU | LLC REFPEREVOZKY | | RUS | BIC |
| 47 | MPC | Mountain Pacific Air Ltd. | Callsign: Mountain Pacific, | CDN | AVCODES |
| 48 | MPC | Mountain Pacific Air | | | ICAO1 |
| 49 | MPCB | MANDA PACKING COMPANY | | | SCAC4 |
| 50 | MPCC | MASTER PETROLEUM CO INC | | | SCAC4 |
| 51 | MPCD | MPC | | | SCAC4 |
| 52 | MPCE | MAPLE DONUTS INC | | | SCAC4 |
| 53 | MPCH | MARDESPACHOS | | | SCAC4 |
| 54 | MPCJ | MOSS, PIERRE C | | | SCAC4 |
| 55 | MPCL | MILES CHEMICAL COMPANY INC | | | SCAC4 |
| 56 | MPCO | MPC TRUCKING LLC | | | SCAC4 |
| 57 | MPCP | MONOPAN CA INC | | | SCAC4 |
| 58 | MPCS | MATERA PAPER COMPANY INC | | | SCAC4 |
| 59 | MPCT | MAXIM PRODUCTION COMPANY, LP | | | SCAC4 |
| 60 | MPCV | MONTECALVO PAVING CORP | | | SCAC4 |
| 61 | MPCW | MISSISSIPP | | | SCAC4 |
| 62 | MPCX | Michels Corp. | 7/2005; eliminated 7/2008 | | NAKINA |
| 63 | MPCX | Michaels Corp. | added 4/2003 | | NAKINA |
| 64 | MPCX | Michaels Pipeline Construction, Inc. | added 4/1991; 1/1994-7/2000; eliminated 4/2003 | | NAKINA |
| 65 | MPCX | Moyer Packing Co. | added 10/1981; eliminated 1/1987 | | NAKINA |
| 66 | MPCX | Mobil Oil Co., a Division of Socony Mobil Oil Co., Inc. | eliminated 10/1962 | | NAKINA |
| 67 | MPCX | Socony Mobil Oil Co., Inc. | 4/1961 | | NAKINA |
| 68 | MPCX | Mobil Oil Co., a Division of Socony Mobil Oil Co., Ltd. | added 1/1960 | | NAKINA |
| 69 | MPCX | Magnolia Petroleum Co. | 8/1920-10/1957; eliminated 1/1960 | | NAKINA |
| 70 | MPCX | Magnolia Petroleum Co. | 4/38-10/57; eliminated 1/60 | | NRHS |
| 71 | MPCX | Mobil Oil Co., a Division of Socony Mobil Oil Co., Ltd. | added 1/60 | | NRHS |
| 72 | MPCX | Socony Mobil Oil Co., Inc. | Apr-61 | | NRHS |
| 73 | MPCX | Moyer Packing Co. | added 10/81; eliminated 1/87 | | NRHS |
| 74 | MPCX | Michels Pipeline Construction, Inc. | added 4/91; 1/94-7/2000 | | NRHS |
| 75 | MPCX | *SOCONY MOBIL OIL CO. [MAGNOLIA PETROLEUM CO.] | | | PWRC |
| 76 | MPCX | *MOYER PACKING CO. | | | PWRC |
| 77 | MPCX | Moyer Packing (Michels Pipeline Construction) | | | RSRV |
| 78 | MPCX | MICHELS CORPORATION | | | SCAC4 |
| 79 | MPCY | MAPLE CITY TRUCKING INC | | | SCAC4 |
| 80 | MPCZ | MISSISSIPPI POWER COMPANY | | | PWRC |
| 81 | MPD | Air Comet, S.A. | IATA: A7, Callsign: Red Comet, IATA Prefix: 352, Ceased operations on 21 December 2009. IATA designator changed from 2Z* | E | AVCODES |
| 82 | MPD | Air Comet, S.A. | IATA: 2Z, Callsign: Red Comet, Established on 23 December 1996 as Air Plus Comet and started operations on 01 March 1997. Name changed from Air Plus Comet, S.A. w.e.f. January 2007. IATA designator changed to A7 | E | AVCODES |
| 83 | MPD | Air Plus Comet, S.A. | IATA: 2Z, Callsign: Red Comet, Established on 23 December 1996. Name changed to Air Comet, S.A. w.e.f. January 2007 | E | AVCODES |
| 84 | MPD | Air Plus Comet | IATA: A7 | | ICAO1 |
| 85 | MPDB | MAINPRIZE, D B TRANSPORT CO | | | SCAC4 |
| 86 | MPDF | MAPLE DALE FARMS | | | SCAC4 |
| 87 | MPDI | MPD INC | | | SCAC4 |
| 88 | MPDK | MPD TRUCKING | | | SCAC4 |
| 89 | MPDN | MPD TRANSPORT INC | | | SCAC4 |
| 90 | MPDR | MATERIAS PRIMAS DE REYNOSA SA DE CV | | | SCAC4 |
| 91 | MPDS | MULTIPRODUCTOS DEPORTIVOS US SA DE | | | SCAC4 |
| 92 | MPDW | MPD WELDING LTD | | | SCAC4 |
| 93 | MPDX | Merchants Despatch Transportation Corp. (reporting marks for Michigan Products Dairy Co.) | 7/1937-1/1941 | | NAKINA |
| 94 | MPDX | Michigan Producers Dairy Co. (Merchants Despatch, Inc.) | 7/1935 | | NAKINA |
| 95 | MPDX | Michigan Products Dairy Co. (Merchants Despatch Transportation Corp.) | Apr-38 | | NRHS |
| 96 | MPDX | MICHIGAN PRODUCTS DAIRY CO. (MERCHANTS DESPATCH TRANSPORTATION CORP.) | | | PWRC |
| 97 | MPDZ | MARTIN DRAKE POWER PLANT | | | PWRC |
| 98 | MPE | Air Norterra Inc, d/b/a Canadian North | IATA: 5T, Callsign: Emphis, IATA Prefix: 518, Founded in 1989. Name changed to Canadian North Inc. ICAO callsign changed to Empress. IATA designator changed from 3F* | CDN | AVCODES |
| 99 | MPE | Air Norterra Inc, d/b/a Canadian North | IATA: 5T, Callsign: Empress, IATA Prefix: 518, Founded in 1989. ICAO designator changed from ANX, ICAO Callsign changed to Norterra | CDN | AVCODES |
| 100 | MPE | Canadian North Inc. | IATA: 5T, Callsign: Empress, IATA Prefix: 518, Founded in 1989. Name changed from Air Norterra Inc, d/b/a Canadian North w.e.f. 07 May 1998. ICAO callsign changed from Emphis. IATA designator changed from 3F* | CDN | AVCODES |
