| 1 | MPA | Mid-Pacific Airlines, Inc. | Callsign: Mid Pac, | USA | AVCODES |
| 2 | MPA | Mid-Pacific Airlines | | | ICAO1 |
| 3 | MPA | York Ry. Co. | added 4/2000; 7/2000-7/2005 | | NAKINA |
| 4 | MPA | Maryland & Pennsylvania R.R. Co. | 1/1975-1/1994; eliminated 4/2000 | | NAKINA |
| 5 | MPA | Maryland & Pennsylvania R.R. Co. | 1/75-1/94; eliminated 4/2000 | | NRHS |
| 6 | MPA | York Ry. Co. | added 4/2000; 7/2000 | | NRHS |
| 7 | MPA | YORK RAILWAY CO. [MARYLAND & PENNSYLVANIA RAILROAD] | | | PWRC |
| 8 | MPA | Maryland and Pennsylvania Railroad (York Railway) | | | RSRV |
| 9 | MPA | Maryland & Pennsylvania R.R. Co. | | USA | TRAFFIC |
| 10 | MPAC | MUCCIPAC | | | SCAC4 |
| 11 | MPAD | MARYLAND PORT AUTHORITY | | | PWRC |
| 12 | MPAD | MPA | | | SCAC4 |
| 13 | MPAE | MT PAN ADVENTURE | | | SCAC4 |
| 14 | MPAF | MAINES PAPER AND FOOD SERVICE INC | | | SCAC4 |
| 15 | MPAJ | MODA PARA AUTOS S DE RL DE | | | SCAC4 |
| 16 | MPAK | MASCO PETROLEUM INC | | | SCAC4 |
| 17 | MPAN | MISSION PRODUCE INC | | | SCAC4 |
| 18 | MPAP | M P AGRI-PRODUCTS | | | SCAC4 |
| 19 | MPAQ | MIKES PAINT AND BODY INC | | | SCAC4 |
| 20 | MPAT | MORENO, PATRICIA | | | SCAC4 |
| 21 | MPAU | MITSUBISHI POLYCRYSTALLINE SILICON AM CO | | USA | BIC |
| 22 | MPAV | MANNON EXCAVATING & PAVING CO INC | | | SCAC4 |
| 23 | MPAW | MT PAN AEGIS | | | SCAC4 |
| 24 | MPAX | MITSUBISHI POWER SYSTEMS AMERICAS, INC. | | | PWRC |
| 25 | MPAX | MITSUBISHI POWER SYSTEMS AMERICAS I | | | SCAC4 |
