| 1 | MST | Aeroamistad, S.A. de C.V. | Callsign: Amistad, | MEX | AVCODES |
| 2 | MST | Master Top Linhas Aereas Ltda | IATA: Q4, Designator Q4* recalled by IATA | BR | AVCODES |
| 3 | MST | Master Top Linhas Aereas Ltda | IATA: BM, Callsign: Master, IATA Prefix: 207, | BR | AVCODES |
| 4 | MST | Martin Steinbrecher GmbH | | DE | VKM |
| 5 | MSTAR | Miejski Zakład Komunikacyjny w Starachowicach | | PL | TRAFFIC |
| 6 | MSTB | MACKENZIE, | | | SCAC4 |
| 7 | MSTC | MISTLETOE TEX-PACK EXPRESS, INC | | | SCAC1 |
| 8 | MSTC | Mamers StCalais | | F | TRAFFIC |
| 9 | MSTD | MASON TRANSPORT SERVICES LTD | | | SCAC4 |
| 10 | MSTE | MUSTEE, E L & SONS INC | | | SCAC4 |
| 11 | MSTG | MAINSTREAM TRANSPORTATION INC | | | SCAC4 |
| 12 | MSTH | MST | | | SCAC4 |
| 13 | MSTJ | MSTL INC | | | SCAC4 |
| 14 | MSTK | M & S TRUCKING | | | SCAC4 |
| 15 | MSTL | Union Pacific R.R. Co. | added 10/1995; 7/2000-7/2005 | | NAKINA |
| 16 | MSTL | Chicago and North Western Ry. Co. | added 1/1995; eliminated 10/1995 | | NAKINA |
| 17 | MSTL | Chicago and North Western Transportation Co. | 1/1975-1/1994; eliminated 1/1995 | | NAKINA |
| 18 | MSTL | Minneapolis & St. Louis Ry. Co. (Chicago and North Western Ry. Co.) | 7/1965-10/1966 | | NAKINA |
| 19 | MSTL | Chicago & North Western Ry. | 4/1961 | | NAKINA |
| 20 | MSTL | Chicago & North Western Ry. | Apr-61 | | NRHS |
| 21 | MSTL | Minneapolis & St. Louis Ry. Co. (Chicago and North Western Ry. Co.) | 7/65-10/66 | | NRHS |
| 22 | MSTL | Chicago and North Western Transportation Co. | 1/75-1/94; eliminated 1/95 | | NRHS |
| 23 | MSTL | Chicago and North Western Ry. Co. | added 1/95; eliminated 10/95 | | NRHS |
| 24 | MSTL | Union Pacific R.R. Co. | added 10/95; 7/2000 | | NRHS |
| 25 | MSTL | UP [CHICAGO & NORTH WESTERN TRANS CO.; MINNEAPOLIS & ST. LOUIS RWY.] | | | PWRC |
| 26 | MSTL | Minneapolis and St. Louis Railway (Union Pacific Railroad) | | | RSRV |
| 27 | MSTL | Minneapolis & St.Louis | | USA | TRAFFIC |
| 28 | MSTM | MARTEL, S TRANSPORT INC | | | SCAC4 |
| 29 | MSTM | Mödlinger Stadtverkehrsmuseum | | A | TRAFFIC |
| 30 | MSTP | MICHIGAN STATE TRUST FOR RAILWAY PRESERVATION | | | PWRC |
| 31 | MSTQ | MUSTIQUE SPORTSWEAR | | | SCAC4 |
| 32 | MSTR | The Massena Terminal R.R. Co. | 1/1975; eliminated 1/1979; 1/1980-1/1994; eliminated 4/1997; 7/2000-7/2005 | | NAKINA |
| 33 | MSTR | The Massena Terminal R.R. Co. | 1/75; eliminated 1/79; 1/80-1/94; eliminated 4/97; 7/2000 | | NRHS |
| 34 | MSTR | MASSENA TERMINAL RAILROAD COMPANY | | | PWRC |
| 35 | MSTR | Massena Terminal Railroad | | | RSRV |
| 36 | MSTU | MSC- MEDITERRANEAN SHIPPING COMPANY S.A. | | CH | BIC |
| 37 | MSTV | METROPOLITAN STEVEDORE | | | PWRC |
