| 9001 | MUGL | MUNGLE TRUCKING INC | | | SCAC4 |
| 9002 | MUGS | MARCUM TRUCKING AND SONS | | | SCAC4 |
| 9003 | MUHL | Betriebe der Stadt Mühlheim | | D | TRAFFIC |
| 9004 | MUHT | MUHL TRANSPORT | | | SCAC4 |
| 9005 | MUHU | MUSTANG JSC | | | SCAC4 |
| 9006 | MUI | Trans Air | IATA: P6, Callsign: Maui, IATA Prefix: 356, Designator P6 recalled by IATA | USA | AVCODES |
| 9007 | MUI | Trans Executive Airlines of Hawaii t/a transair Express | IATA: 5H, Callsign: Maui, Operates transair Express SD360 Fleet. Designator 5H recalled by IATA | USA | AVCODES |
| 9008 | MUI | Trans Executive Airlines of Hawaii t/a transair Express | IATA: R9, Callsign: Maui, Operates transair Express SD360 Fleet. ICAO callsign changed to Transair. Designator 5H recalled by IATA | USA | AVCODES |
| 9009 | MUI | Trans Air | Callsign: Maui, Designator P6 recalled by IATA | USA | AVCODES |
| 9010 | MUI | Trans Executive Airlines of Hawaii t/a transair Express | IATA: R9, Callsign: Transair, Operates transair Express SD360 Fleet. ICAO callsign changed from Maui. Designator 5H recalled by IATA | USA | AVCODES |
| 9011 | MUI | Trans Air | | | ICAO1 |
| 9012 | MUII | M C U INTERMODAL INC | | | SCAC4 |
| 9013 | MUIK | MITSUI-SOKO CO LTD | | | SCAC4 |
| 9014 | MUIR | MUIRS CARTAGE LIMITED | | | SCAC4 |
| 9015 | MUJJ | MULLIS TRUCKING | | | SCAC4 |
| 9016 | MUK | Muk Air | IATA: ZR, Callsign: Mukair, IATA Prefix: 796, Designator ZR recalled by IATA | DK | AVCODES |
| 9017 | MUK | Muk Air | Callsign: Mukair, Ceased operations on 05 November 2001. Designator ZR recalled by IATA | DK | AVCODES |
| 9018 | MUKC | MONK TRUCKING CO LLC | | | SCAC4 |
| 9019 | MUKE | MUSKET TRANSPORT LTD, THE | | | SCAC4 |
| 9020 | MUKF | MUNDO TRUCKING INC | | | SCAC4 |
| 9021 | MUKG | MARS TRUCKING | | | SCAC4 |
| 9022 | MUKI | MAR TRUCKING | | | SCAC4 |
| 9023 | MUKL | MORT TRUCKING LLC | | | SCAC4 |
| 9024 | MUKN | MULLIKIN, MICHAEL L TRUCKING CO | | | SCAC4 |
| 9025 | MUKO | MAXWELL, ROBERT TRUCKING LTD | | | SCAC4 |
| 9026 | MUKT | MUSKOKA TRANSPORT LIMITED | | | SCAC4 |
| 9027 | MUKU | DEN HARTOGH GLOBAL BV | | NL | BIC |
| 9028 | MUKU | MUTO CO LTD | | | SCAC4 |
| 9029 | MUKY | MOUNTAIN CREEK TAXIDERMY | | | SCAC4 |
| 9030 | MUL | Mokulele Flight Service, Inc. | IATA: MW, Callsign: Mokulele, IATA Prefix: 415, ICAO designator changed to MHO. ICAO designator changed from BUG. ICAO callsign changed from Speedbuggy. IATA designator changed from 5Z* | USA | AVCODES |
| 9031 | MULA | MCCORMICKS USA LOGISTICS INCORPORAT | | | SCAC4 |
| 9032 | MULC | MAGNUM LOGISTICS | | | SCAC4 |
| 9033 | MULC | Mulleys Coaches | | GB | TRAFFIC |
| 9034 | MULD | MULTI-LOAD TRANSPORT INC | | | SCAC4 |
| 9035 | MULE | MULTIMATIC TECHNICAL CENTRE (DIV OF | | | SCAC4 |
| 9036 | MULG | MULGREW OIL CO | | | SCAC4 |
| 9037 | MULH | MULTI TECH | | | SCAC4 |
| 9038 | MULH | Soléa | City: Mulhouse | F | TRAFFIC |
| 9039 | MULI | MULTIMODAL INTERNATIONAL SHIPPING I | | | SCAC4 |
| 9040 | MULL | MULLINS LEASING SERVICE INC | | | SCAC4 |
| 9041 | MULLER | Müller Gleisbau AG | | CH | TRAFFIC |
| 9042 | MULM | MULLEN TRUCKING LP | | | SCAC4 |
| 9043 | MULN | MULLEN BROS OF NORTH ADAMS MASS INC | | | SCAC4 |
| 9044 | MULO | MULLER TRANSPORT | | | SCAC4 |
| 9045 | MULQ | MULTILINE TRANSPORT LTD | | | SCAC4 |
| 9046 | MULT | MULE TEAM EXPRESS INC | | | SCAC4 |
| 9047 | MULV | MULVANIA TRUCKING CO | | | SCAC4 |
| 9048 | MULX | TEMPORARY - O/T DIV. | | | PWRC |
| 9049 | MULY | MULAY EXPRESS | | | SCAC4 |
| 9050 | MUMD | MUMMA | | | SCAC4 |
| 9051 | MUME | MURPHY MOTOR EXPRESS, INC | | | SCAC1 |
| 9052 | MUMH | MINUTE MAN TRANSPORT, INC | | | SCAC1 |
| 9053 | MUMH | MINUTEMA | | | SCAC4 |
| 9054 | MUMO | MURRAY MOTORS INC | | | SCAC4 |
| 9055 | MUMP | MOMENTUM LOGISTICS CORP | | | SCAC4 |
| 9056 | MUMT | MULTI-MODAL TRANSPORT INC | | | SCAC4 |
| 9057 | MUMU | INTERRAIL EUROPE GMBH | | D | BIC |
| 9058 | MUMU | MULTIMODAL TRANSPORT EQUIPMENT GMBH | | | SCAC4 |
| 9059 | MUN | Aeromundo Ejecutivo, S.A. de C.V. | Callsign: Aeromundo, | MEX | AVCODES |
| 9060 | MUN | Aeromundo Ejecutivo | | | ICAO1 |
| 9061 | MUN | N=Traffic and Tariff Association ;G=Verkehrsverbund;H=Közlekedési szövetség; | Real: MVV, City: München, Common livery of vehicles of the contracting partners | D | TRAFFIC |
| 9062 | MUNA | MURO NORTH AMERICA INC | | | SCAC4 |
| 9063 | MUNH | MUNRO HONEY | | | SCAC4 |
| 9064 | MUNI | SAN FRANCISCO MUNICIPAL RWY | | | PWRC |
| 9065 | MUNI | Municipial Railway San Francisco | City: San Francisco | USA | TRAFFIC |
| 9066 | MUNN | MUNNS, DAVID A TRUCKING INC | | | SCAC4 |
| 9067 | MUNT | MOUNTAIN MAN TRUCKING | | | SCAC4 |
| 9068 | MUNX | Mather Stock Car Co. | 7/1937-7/1954; eliminated 1/1955 | | NAKINA |
| 9069 | MUNX | Mather Refrigerator Express (Mather Stock Car Co.) | Apr-38 | | NRHS |
| 9070 | MUNX | Mather Stock Car Co. | Jan-52 | | NRHS |
| 9071 | MUNX | MATHER STOCK CAR CO. | | | PWRC |
| 9072 | MUOC | MUTUAL OIL CO INC | | | SCAC4 |
| 9073 | MUOE | MOES TRANSPORT TRUCKING INC | | | SCAC4 |
| 9074 | MUOU | MARGUISA SHIPPING LINES | | E | BIC |
| 9075 | MUPC | MURPHY, M J OIL COMPANY | | | SCAC4 |
| 9076 | MUPT | MOUNTAIN PETROLEUM | | | SCAC4 |
| 9077 | MUQK | MAC CAPEHART TRUCKING LLC | | | SCAC4 |
| 9078 | MUR | Aerolinea Muri | Callsign: Muri, | MEX | AVCODES |
| 9079 | MUR | Aerolinea Muri | | | ICAO1 |
| 9080 | MURAD | IP Muradaliev | City: Saratov | RUS | TRAFFIC |
| 9081 | MURB | MURSAU TRANSPORT LLC | | | SCAC4 |
| 9082 | MURD | MURRYS | | | SCAC4 |
| 9083 | MURE | MURRAY ENTERPRISES LTD | | | SCAC4 |
| 9084 | MURG | MUR SHIPPING BV (DIV OF MUR | | | SCAC4 |
| 9085 | MURI | MURILLOS TRUCKING | | | SCAC4 |
| 9086 | MURK | MURDOCK TRANSPORT | | | SCAC4 |
| 9087 | MURM | MURRAYS MOVING & STORAGE INC | | | SCAC4 |
| 9088 | MURT | MURPHY TRANSPORT INC | | | SCAC4 |
| 9089 | MURU | FRAMATOME SAS | | F | BIC |
| 9090 | MURV | MURPH-TRANS LLC | | | SCAC4 |
| 9091 | MURW | MURRILL TRUCKING | | | SCAC4 |
| 9092 | MURX | Mutual Refining Co. (Superior Oil Works) | 7/1935 | | NAKINA |
| 9093 | MURX | Mutual Refining Co. | 8/1920-7/1932 | | NAKINA |
| 9094 | MURX | MUTUAL REFINING CO. | | | PWRC |
| 9095 | MURY | MURPHY | | | SCAC4 |
| 9096 | MUS | Air Adelphi Ltd. | Callsign: Adelphi, | WV | AVCODES |
| 9097 | MUS | | | CZ | TRAFFIC |
| 9098 | MUS | Mostecká uhelná a.s. | | CZ | VKM |
| 9099 | MUSAK | Musashino Kotsu Bus Co. | | J | TRAFFIC |
| 9100 | MUSC | Memphis Union Station Co. | 1/1975-7/2005 | | NAKINA |
