| 1 | MTS | Mantrust Asahi Airways, PT | Callsign: Mantrust, | RI | AVCODES |
| 2 | MTS | Med Jets, S.A. de C.V. t/a Jet Rescue Air Ambulance | Callsign: Medservice, | MEX | AVCODES |
| 3 | MTS | Mantrust Asahi Airways | | | ICAO1 |
| 4 | MTS | San Diego Metropolitan Transit System | | USA | TRAFFIC |
| 5 | MTSA | MATSON TRANSPORT INC | | | SCAC4 |
| 6 | MTSB | METRO TRUCK SERVICES & L | | | SCAC4 |
| 7 | MTSC | MARUBENI TRANSPORT SERVICE CORP | | | SCAC4 |
| 8 | MTSG | MTS LOGISTICS INC | | | SCAC4 |
| 9 | MTSH | MCINTOSH, J & R FEEDS INC | | | SCAC4 |
| 10 | MTSI | MEDICAL TRANSPORT SERVICES INC | | | SCAC4 |
| 11 | MTSJ | MTS TRANSPORTATION INC | | | SCAC4 |
| 12 | MTSK | MILLION DOLLAR TRANSPORT | | | SCAC4 |
| 13 | MTSL | MERCANTILE TRUCKING SERVICE LIMITED | | | SCAC4 |
| 14 | MTSM | MCCAIN TRAFFIC SUPPLY MEXICO S A DE | | | SCAC4 |
| 15 | MTSN | MOST TRUCKING SERVICE LLC, THE | | | SCAC4 |
| 16 | MTSO | MILLARD TRANSPORTATION SERVICES | | | SCAC4 |
| 17 | MTSP | MASHBURN TRANSPORTATION SERVICES IN | | | SCAC4 |
| 18 | MTSR | MADISON TRANSPORT SERVICES LLC | | | SCAC4 |
| 19 | MTST | MATS TRUCKING CORP | | | SCAC4 |
| 20 | MTSU | SEACUBE CONTAINERS LLC | | USA | BIC |
| 21 | MTSU | MARINE TRANSPORT SERVICE INC | | | PWRC |
| 22 | MTSU | Marine Transport Service | | | RSRV |
| 23 | MTSU | MODULAR TRANSPORTATION SYSTEMS | | | SCAC4 |
| 24 | MTSV | MERLIN TRANSPORTATION SERVICES, INC | | | SCAC1 |
| 25 | MTSV | MARINE TRANSPORTATION SERVICES INC | | | SCAC4 |
| 26 | MTSX | Max Transportation Service | added 10/1963; 7/1965-4/1970; eliminated 7/1973 | | NAKINA |
| 27 | MTSX | Max Transportation Service | 7/65-4/70; eliminated 7/73 | | NRHS |
| 28 | MTSX | MAX TRANSPORTATION SERVICE | | | PWRC |
| 29 | MTSX | Max Transportation Service | | USA | TRAFFIC |
| 30 | MTSY | MED TECH SOLUTIONS LLC | | | SCAC4 |
