| 1 | MB | MNG Airlines Cargo | ICAO: MNB, Callsign: Black Sea, IATA Prefix: 716, Name changed to MNG Airlines. Designator MB reinstated by IATA | TR | AVCODES |
| 2 | MB | Execaire, Inc. | ICAO: EXA, Callsign: Canadian Execaire, Designator MB* recalled by IATA | CDN | AVCODES |
| 3 | MB | Malasyia Air Charter Company Ltd. | Callsign: Malaysia, | MAL | AVCODES |
| 4 | MB | Federal Express Corporation (Fedex) | ICAO: FDE, Callsign: Express, ICAO designator changed to FDX | USA | AVCODES |
| 5 | MB | MNG Airlines | ICAO: MNB, Callsign: Black Sea, IATA Prefix: 716, Name changed to MNG Airlines Cargo. Designator MB reinstated by IATA | TR | AVCODES |
| 6 | MB | Federal Express Corporation (Fedex) | ICAO: FDX, Callsign: Express, ICAO designator changed from FDE | USA | AVCODES |
| 7 | MB | M&B R.R., LLC | added 10/1997; 7/2000-7/2005 | | NAKINA |
| 8 | MB | Meridian & Bigbee R.R. Co. | 1/1975-1/1994; eliminated 10/1997 | | NAKINA |
| 9 | MB | Montpelier & Barre R.R. | 1/1975-1/1980; eliminated 1/1981 | | NAKINA |
| 10 | MB | Montpelier & Barre R.R. | 1/75-1/80; eliminated 1/81 | | NRHS |
| 11 | MB | Meridian & Bigbee R.R. Co. | 1/75-1/94; eliminated 10/97 | | NRHS |
| 12 | MB | M&B R.R., L.L.C. | added 10/97; 7/2000 | | NRHS |
| 13 | MB | *MONTPELIER & BARRE RAILROAD CO. | | | PWRC |
| 14 | MB | +M & B RAILROAD, LLC [MERIDIAN & BIGBEE RR CO.] | | | PWRC |
| 15 | MB | Meridian and Bigbee Railroad (M&B Railroad) | | | RSRV |
| 16 | MB | M & B RAILROAD LLC | | | SCAC4 |
| 17 | MB | Mercedes-Benz | | D | TRAFFIC |
| 18 | MB | Mansfelder Bergwegsbahn e.V | | DE | VKM |
| 19 | MBA | Automobilvertriebs Aktiengesellschaft | Callsign: Avag Air, Ceased operations. | A | AVCODES |
| 20 | MBA | Avag Air Fur Luftfahrt | Callsign: Avag Air, | A | AVCODES |
| 21 | MBA | Avag Air | | | ICAO1 |
| 22 | MBAB | MURRAY, BOB TRUCKING | | | SCAC4 |
| 23 | MBAD | MBA LOGISTICS LLC | | | SCAC4 |
| 24 | MBAE | MEDLINS BALE CARRIERS INC | | | SCAC4 |
| 25 | MBAG | MAYER BROTHERS APPLE PRODUCTS INC | | | SCAC4 |
| 26 | MBAH | M & B TANK LINES INC | | | SCAC4 |
| 27 | MBAK | MARKET BASKET | | | SCAC4 |
| 28 | MBAL | MERX GLOBAL LOGISTICS INC | | | SCAC4 |
| 29 | MBAN | MEBANE TRANSPORT COMPANY | | | SCAC4 |
| 30 | MBAP | MURRAY, BOB TRANSPORTATION LLC | | | SCAC4 |
| 31 | MBAS | MILLER, B A & SONS TRUCKING INC | | | SCAC4 |
| 32 | MBAU | MARTI INFRA AG | | CH | BIC |
| 33 | MBAU | MARTI INFRA AG | | | SCAC4 |
| 34 | MBAV | MT BALTIC ADONIA TANKSCIFFAHRTSGESE | | | SCAC4 |
| 35 | MBAW | MICHELE BOTTIGLIERI ARMATORE SPA | | | SCAC4 |
| 36 | MBB | Air Manas d/b/a Air Manas Ltd. Air Company | IATA: M2, Callsign: Air Manas, Founded in 2006. IATA designator changed to ZM | KS | AVCODES |
| 37 | MBB | Air Manas d/b/a Air Manas Ltd. Air Company | IATA: ZM, Callsign: Air Manas, Founded in 2006. Ceased operations. IATA designator changed to M2* | KS | AVCODES |
| 38 | MBB | Air Manas Air Company LLC | IATA: ZM, Callsign: Air Manas, IATA Prefix: 887, | KS | AVCODES |
| 39 | MBB | Air Manas | | | ICAO1 |
| 40 | MBB | Mansfelder Bergwerksbahn Verein e.V. | Benndorf | D | privat-bahn.de |
| 41 | MBB | Mecklenburgische Bäderbahn Molli | | DE | VKM |
| 42 | MBBA | MACK BROTHERS TRUCKING | | | SCAC4 |
| 43 | MBBB | Museumsbahn Bremerhaven-Bederkesa e. V. | | DE | VKM |
| 44 | MBBC | MACARBO INC | | | SCAC4 |
| 45 | MBBE | MYKLEBU | | | SCAC4 |
| 46 | MBBK | MAHONE BAY BOATWORKS | | | SCAC4 |
| 47 | MBBKB | Buckower Kleinbahn-Eisenbahnverein Märkische Schweiz e.V | | DE | VKM |
| 48 | MBBL | MAAN | | | SCAC4 |
| 49 | MBBT | MORRIS, B BROTHERS TRUCKING | | | SCAC4 |
| 50 | MBBU | MULTIBOXX LIMITED | | HK | BIC |
| 51 | MBBX | Tank Car Services, Inc. | added 1/1981; eliminated 1/1986 | | NAKINA |
| 52 | MBBX | Michael D. Boxberger | added 1/1980; 1/1980; eliminated 1/1981 | | NAKINA |
| 53 | MBBX | Michael D. Boxberger | added 1/80; 1/80; eliminated 1/81 | | NRHS |
| 54 | MBBX | Tank Car Services, Inc. | added 1/81; eliminated 1/86 | | NRHS |
| 55 | MBBX | TANK CAR SERVICES, INC. [MICHAEL D. BOXBERGER] | | | PWRC |
| 56 | MBBX | Tank Car Services Inc. | | | RSRV |
| 57 | MBC | Airjet Exploracao Aerea de Carga, Passageiros e Correios, Lda | Callsign: Mabeco, | ANG | AVCODES |
| 58 | MBC | Airjet Exploracao Aerea De Carga | | | ICAO1 |
| 59 | MBC | Transports de la région Morges–Biere–Cossonay | | CH | TRAFFIC |
| 60 | MBC | Transports de la région Morges-Bière-Cossonay | | CH | VKM |
| 61 | MBCB | MTI BUS COMPANY | | | SCAC4 |
| 62 | MBCC | MARBLE CLIFF OIL CO | | | SCAC4 |
| 63 | MBCE | MALLETTE BROTHERS CONSTRUCTION COMP | | | SCAC4 |
| 64 | MBCH | MAIBACH TRACTOR LLC | | | SCAC4 |
| 65 | MBCI | MISSOULA BOTTLING COMPANY INC | | | SCAC4 |
| 66 | MBCJ | MARTINEZ BRIONES, CLAUDIA JULIANA | | | SCAC4 |
| 67 | MBCK | M B TRUCKING INC | | | SCAC4 |
| 68 | MBCL | MAILBOAT COMPANY LTD, THE | | | SCAC4 |
| 69 | MBCO | MABCO TRANSIT INC | | | SCAC4 |
| 70 | MBCQ | M & B CARRIERS INC | | | SCAC4 |
| 71 | MBCR | MANBECK, LARRY W | | | SCAC4 |
| 72 | MBCS | MONTREAL BEST CARRIER INC | | | SCAC4 |
| 73 | MBCV | MOORE, BENJAMIN & CO | | | SCAC4 |
| 74 | MBCW | MATHEWS BROTHERS COMPANY | | | SCAC4 |
| 75 | MBCX | Chicago Freight Car Leasing Co. | added 4/2007 | | NAKINA |
| 76 | MBCX | M.B.C.X. Leasing, LLC | added 7/1998; 7/2000; eliminated 4/2003; 7/2005 (not listed) | | NAKINA |
| 77 | MBCX | Material Brokerage Co. | added 10/1996; eliminated 7/1998 | | NAKINA |
| 78 | MBCX | The Mann Bros. Co. | 8/1920-7/1935 | | NAKINA |
| 79 | MBCX | Material Brokerage Co. | added 10/96; eliminated 7/98 | | NRHS |
| 80 | MBCX | M.B.C.X. Leasing, L.L.C. | added 7/98; 7/2000 | | NRHS |
| 81 | MBCX | *MANN BROS. CO. | | | PWRC |
| 82 | MBCX | +CHICAGO FREIGHT CAR LEASING CO. [M.B.C.X. LEASING, LLC; MATERIAL BROKERAGE COMPANY] | | | PWRC |
| 83 | MBCX | M.B.C.X. Leasing (Chicago Freight Car Leasing) | | | RSRV |
| 84 | MBCX | CHICAGO FREIGHT CAR LEASING CO | | | SCAC4 |
| 85 | MBCY | MOBSTER COMPANY LLC | | | SCAC4 |
| 86 | MBDC | MOBELL DISTRIBUTION CORPORATION | | | SCAC4 |
| 87 | MBDK | M B D TRUCKING LTD | | | SCAC4 |
| 88 | MBDL | MOBILEMED TRANSPORTATION SERVICES L | | | SCAC4 |
| 89 | MBDP | MBD TRANSPORT INC | | | SCAC4 |
| 90 | MBDT | MBD TRANSPORTATION INC | | | SCAC4 |
| 91 | MBDU | MULTIBOXX LIMITED | | HK | BIC |
| 92 | MBDY | MOORE, BUDDY TRUCKING INC | | | SCAC4 |
| 93 | MBE | Martin-Baker Ltd. | Callsign: Martin, | GB | AVCODES |
| 94 | MBE | Martin-Baker | | | ICAO1 |
| 95 | MBE | Müllheim-Badenweiler-Eisenbahn | | D | TRAFFIC |
| 96 | MBEC | MISS BECKYS SEAFOOD INC | | | SCAC4 |
| 97 | MBEG | MERBEN ENTERPRISES INC | | | SCAC4 |
| 98 | MBEN | MANDER BROS ENTERPRISES LTD | | | SCAC4 |
| 99 | MBEQ | MOBILE FORCE EQUIPMENT LLC | | | SCAC4 |
| 100 | MBER | ME! BATH EXPERIENCE INC | | | SCAC4 |
