| 1 | IB | Inntalbahn KG | | DE | VKM |
| 2 | IBA | Lineas Aereas Iberoamericanas | Callsign: Aerolai, | RCH | AVCODES |
| 3 | IBAB | Inlandsbanan AB | 1993 - | S | svenska-lok.se |
| 4 | IBAB | Inlandsbanan AB | 1993 - | S | TRAFFIC |
| 5 | IBAB | Inlandsbanan AB | | SE | VKM |
| 6 | IBAI | IBAIZABAL MANAGEMENT SERVICES S L | | | SCAC4 |
| 7 | IBAR | IBARRA RAMOS, JOSE JAIME | | | SCAC4 |
| 8 | IBAT | IBARRAS TRUCKING | | | SCAC4 |
| 9 | IBB | Binter Canarias, S.A. | IATA: NT, | E | AVCODES |
| 10 | IBB | Binter Canarias | IATA: NT | | ICAO1 |
| 11 | IBB | Binter Canarias | | E | TRAFFIC |
| 12 | IBBT | INNER BAY BOATS | | | SCAC4 |
| 13 | IBBU | U B C LTD | | | SCAC4 |
| 14 | IBC | Ibicenca Air, S.L. | Callsign: Ibicence, | E | AVCODES |
| 15 | IBC | Ibex Air Charter S.A.R.L. | Callsign: Ibex Charter, | RL | AVCODES |
| 16 | IBC | Ibicenca Air | | | ICAO1 |
| 17 | IBC | Imperial Bus Company | City: Rainham (Essex) | GB | TRAFFIC |
| 18 | IBCK | IBC TRUCKING LLC | | | SCAC4 |
| 19 | IBCO | I B C | | | SCAC4 |
| 20 | IBCQ | INTERNATIONAL BONDED COURIERS INC | | | SCAC4 |
| 21 | IBCT | IBRAHIM TRUCKING | | | SCAC4 |
| 22 | IBCU | DEN HARTOGH DRY BULK LOGISTICS LTD | | GB | BIC |
| 23 | IBCU | U B C LTD | | | SCAC4 |
| 24 | IBCX | Indiana Boxcar Corp. | 7/2000-7/2005 (not listed) | | NAKINA |
| 25 | IBCX | Iowa State Brand Creameries (North Western Refrigerator Line Co.) | 7/1935 | | NAKINA |
| 26 | IBCX | TTX Co. | added 10/2003 | | NAKINA |
| 27 | IBCX | Indiana Boxcar Corp. | Jul-00 | | NRHS |
| 28 | IBCX | INDIANA BOXCAR CORPORATION | | | PWRC |
| 29 | IBCX | Indiana Boxcar Corporation | | | RSRV |
| 30 | IBCX | INDIANA BOXCAR CORPORATION | | | SCAC4 |
| 31 | IBDC | IBARRA, FRANCISCO TRUCKING | | | SCAC4 |
| 32 | IBE | Iberia Airlines | IATA: IB | | ICAO1 |
| 33 | IBER | Iberia | | E | TRAFFIC |
| 34 | IBERC | IBERCARGORAIL, S.A. | | ES | VKM |
| 35 | IBERT | IBERTIF FERROCARRILES, S.A. | | ES | VKM |
| 36 | IBF | Ing Büro Förster | | DE | VKM |
| 37 | IBFU | DEN HARTOGH DRY BULK LOGISTICS LTD | | GB | BIC |
| 38 | IBG | Ice Bridge | Callsign: Springfield Air, | USA | AVCODES |
| 39 | IBG | Springfield Air | Callsign: Ice Bridge, | USA | AVCODES |
| 40 | IBIA | IBI ARMORED SERVICES INC | | | SCAC4 |
| 41 | IBIC | INFLATABLE BOATWORKS INC | | | SCAC4 |
| 42 | IBIS | IBIS SHIPPING LLC | | | SCAC4 |
| 43 | IBIT | IBI SECURED TRANSPORT INC | | | SCAC4 |
| 44 | IBJ | Air Taxi & Charter International, S.L. | Callsign: Ibertaxi, | E | AVCODES |
| 45 | IBK | Norwegian Air International Ltd. | IATA: D8, Callsign: Nortrans, IATA Prefix: 329, IATA designator changed to D8 | IRL | AVCODES |
| 46 | IBK | Norwegian Air International Ltd. | IATA: D8, Callsign: Nortrans, IATA Prefix: 329, IATA designator changed from D8* | IRL | AVCODES |
| 47 | IBK | Norwegian Air International Ltd. | IATA: D8, Callsign: Nortrans, IATA designator changed from D8* | IRL | AVCODES |
| 48 | IBKM | INDUSTRIAL BUCKETS DE MEXICO SA DE | | | SCAC4 |
| 49 | IBKU | INTERBULK,INC | | USA | BIC |
| 50 | IBKU | Interbulk,Inc | | | RSRV |
| 51 | IBL | IBL Aviation Ltd | Callsign: Catovair, | MUS | AVCODES |
| 52 | IBL | IBL Aviation | | | ICAO1 |
| 53 | IBL | Ingenierbüro Lohr | | DE | VKM |
| 54 | IBLC | I & B LOGISTICS INC | | | SCAC4 |
| 55 | IBLD | IRONLAKE BUSINESS LTD | | | SCAC4 |
| 56 | IBLT | IBL TRANSPORT CO LTD | | | SCAC4 |
| 57 | IBLU | INBULK TECHNOLOGIES LTD | | GB | BIC |
| 58 | IBLU | INBULK TECHNOLOGIES LTD | | | SCAC4 |
| 59 | IBME | INTERLINES - BLANKENSHIP MTR | | | PWRC |
| 60 | IBMS | IBARRAS IMPORTS | | | SCAC4 |
| 61 | IBMU | JSC INFOTECH-BALTIKA-M | | RUS | BIC |
| 62 | IBMZ | INTERNATIONAL BUSINESS CORP. | | | PWRC |
| 63 | IBN | INDUSTRIAL BUS LINES INC | | | SCAC4 |
| 64 | IBNU | INTERPOOL CONTAINER PTY LIMITED | | | PWRC |
| 65 | IBNU | Interpool Container Pty | | | RSRV |
| 66 | IBOX | TTX Co. | added 10/2003; 7/2005 | | NAKINA |
| 67 | IBOX | TTX CO. | | | PWRC |
| 68 | IBOX | TTX COMPANY | | | SCAC4 |
| 69 | IBPX | Trinity Industries Leasing Co. | added 7/1995; 7/2000-7/2005 | | NAKINA |
| 70 | IBPX | IBP, Inc. | added 5/1983; 1/1994; eliminated 7/1995 | | NAKINA |
| 71 | IBPX | Merchants Despatch Transportation Corp. | added 1/1961; 4/1961-4/1970; eliminated 1/1973 | | NAKINA |
| 72 | IBPX | Merchants Despatch Transportation Corp. | 4/61-4/70; eliminated 1/73 | | NRHS |
| 73 | IBPX | IBP, Inc. | added 5/83; 1/94; eliminated 7/95 | | NRHS |
| 74 | IBPX | Trinity Industries Leasing Co. | added 7/95; 7/2000 | | NRHS |
| 75 | IBPX | *MERCHANTS DESPATCH TRANSPORTATION CORP. | | | PWRC |
| 76 | IBPX | +TRINITY INDUSTRIES LEASING COMPANY (TYSON FOODS, INC., LESSEE)[IBP, INC; IOWA BEEF PACKERS] | | | PWRC |
| 77 | IBPX | Iowa Beef Packers (Trinity Industries Leasing Co.) | | | RSRV |
| 78 | IBPX | IBP, INC. | | | SCAC4 |
| 79 | IBR | Ibertour Servicios Aereos S.L.U. | Callsign: Ibertour, | E | AVCODES |
| 80 | IBR | Ibertour Servicios Aereos | | | ICAO1 |
| 81 | IBR | IRON BULL RAILROAD CO. | | | PWRC |
| 82 | IBR | IRON BULL RAILORAD COMPANY | | | SCAC4 |
| 83 | IBRR | IBARRA ESPINOZA, VICTOR H | | | SCAC4 |
| 84 | IBRU | IBERO LINES | | | SCAC4 |
| 85 | IBS | IBIS | Callsign: Spider, | B | AVCODES |
| 86 | IBS | Flying Partner | | B | AVCODES |
| 87 | IBS | Compania Operadora de Corto y Medio Radio Iberia Express, S.A.U | IATA: I2, Callsign: Iberexpres, IATA Prefix: 060, | E | AVCODES |
| 88 | IBSH | I BEAM SHIPPING COMPANY LIMITED | | | SCAC4 |
| 89 | IBSP | I BLADE SHIPPING COMPANY LIMITED | | | SCAC4 |
| 90 | IBSR | INGRAM BROTHERS SERVICES LLC | | | SCAC4 |
| 91 | IBSW | ICE BIRD SHIPPING SA | | | SCAC4 |
| 92 | IBSY | INLAND BARGE SERVICE INC | | | SCAC4 |
| 93 | IBT | Ibertrans Aerea, S.L. | Callsign: Ibertrans, | E | AVCODES |
| 94 | IBT | Ibertrans Aerea | | | ICAO1 |
| 95 | IBT | International Bridge & Terminal Co. | 1/1975-1/1994; added 7/1998; 7/2000-7/2005 | | NAKINA |
| 96 | IBT | International Bridge & Terminal Co. | 1/75-1/94; added 7/98; 7/2000 | | NRHS |
| 97 | IBT | INTERNATIONAL BRIDGE & TERMINAL | | | PWRC |
| 98 | IBT | International Bridge and Terminal | | | RSRV |
| 99 | IBT | INTERNATIONAL BRIDGE AND TERMINAL C | | | SCAC4 |
| 100 | IBT | International Bridge & Terminal Co. | | USA | TRAFFIC |
