| 901 | IEDI | INTRACOASTAL EXPEDITED & DELIVERY I | | | SCAC4 |
| 902 | IEDN | IOWA EXPRESS DELIVERY INC | | | SCAC4 |
| 903 | IEEL | INTERNATIONAL ENTERTAINMENT EQUIPME | | | SCAC4 |
| 904 | IEET | I E TRANSPORT INC | | | SCAC4 |
| 905 | IEFS | INLAND EMPIRE FREIGHT SYSTEMS INC | | | SCAC4 |
| 906 | IEI | Esercito Italiano | Callsign: Italian Army, | I | AVCODES |
| 907 | IEII | IMPORT-EXPORT IMPERIAL INC | | | SCAC4 |
| 908 | IEIN | IMER EXPRESS INC | | | SCAC4 |
| 909 | IEIQ | INTERMODAL EXPRESS INC | | | SCAC4 |
| 910 | IEIR | IRISH EXPRESS INC | | | SCAC4 |
| 911 | IEIS | INDIEN EXPRESS INC | | | SCAC4 |
| 912 | IEJ | Inflite Limited | Callsign: Swan, | GB | AVCODES |
| 913 | IEK | INAER Euskadi, S.A. | Callsign: Inaer Euskadi, | E | AVCODES |
| 914 | IELA | INVODANE ENGINEERING LTD | | | SCAC4 |
| 915 | IELC | INTEGRITY EXPRESS LOGISTICS LLC | | | SCAC4 |
| 916 | IELD | IRISH EXPRESS LTD | | | SCAC4 |
| 917 | IELE | INTERSTATE EXPRESS LLC | | | SCAC4 |
| 918 | IELI | INTEGRITY EXPRESS LOGISTICS | | | SCAC4 |
| 919 | IELN | INTERNATIONAL EXPRESS LOGISTICS INC | | | SCAC4 |
| 920 | IELO | INFINITE EXPRESS LOGISTICS LLC | | | SCAC4 |
| 921 | IELQ | IEL FORWARDING SYSTEM INC. | | | SCAC4 |
| 922 | IELT | I E L TRANSPORT INC | | | SCAC4 |
| 923 | IELU | INTERNATIONAL EQUIPMENT LEASING INC | | | SCAC4 |
| 924 | IELZ | IRAN EXPRESS LINES | | | PWRC |
| 925 | IELZ | Iran Express Lines | | | RSRV |
| 926 | IELZ | IRAN EXPRESS LINES | | | SCAC4 |
| 927 | IEMA | INTERSTATE EXPRESS MESSENGER | | | SCAC4 |
| 928 | IEMU | INTERNATIONAL EQUIPMENT MARKETING I | | | SCAC4 |
| 929 | IEP | Elipiu | Callsign: Elipiu, | I | AVCODES |
| 930 | IEPA | ITO EL PASO | | | SCAC4 |
| 931 | IEPI | INTERMODAL EXPRESS INC | | | SCAC4 |
| 932 | IEPN | INTERSTATE EXPRESS INC | | | SCAC4 |
| 933 | IEPS | INDUSTRIAS ELECTRONICAS PACIFICO SA | | | SCAC4 |
| 934 | IEQM | IRVING EQUIPMENT LTD | | | SCAC4 |
| 935 | IERR | Indiana Eastern Rd. LLC | added 10/2005; eliminated 1/2008 | | NAKINA |
| 936 | IERR | INDIANA EASTERN RAILROAD, LLC. | | | PWRC |
| 937 | IERR | INDIANA EASTERN RAILROAD LLC | | | SCAC4 |
| 938 | IERT | INDIANA EASTERN RAILROAD & TRANSPORTATION, INC. | | | PWRC |
| 939 | IERX | General American Transportation Corp. | 1/1950-1/1952; eliminated 10/1953 | | NAKINA |
| 940 | IERX | Inland-Empire Refineries Inc. | 1/1941-4/1947 | | NAKINA |
| 941 | IERX | General American Transportation Corp. | 1/52; eliminated 10/53 | | NRHS |
| 942 | IERX | *INLAND-EMPIRE REFINERIES, INC. | | | PWRC |
| 943 | IERX | *GENERAL AMERICAN TRANSPORTATION CORP | | | PWRC |
| 944 | IES | Gomel Engineer's Institute of the Ministry for Emergency Situations | | BY | AVCODES |
| 945 | IES | Inter-Island Air Services Ltd. | IATA: QW, Callsign: Inter Island, Desigantor QW recalled by IATA | WG | AVCODES |
| 946 | IESC | INTERNATIONAL EXHIBITION SERVICES I | | | SCAC4 |
| 947 | IESD | INGENIERIA EN SISTEMAS DE OPERACION | | | SCAC4 |
| 948 | IESG | INLAND EMPIRE STAGES LTD | | | SCAC4 |
| 949 | IESL | INTERNATIONAL EQUIPMENT SALES & LEA | | | SCAC4 |
| 950 | IESN | INTERRA ENERGY SERVICES INTERNATION | | | SCAC4 |
| 951 | IESO | INTERNATIONAL EQUIPMENT SALES CO | | | SCAC4 |
| 952 | IESP | INTERMODAL EXPRESS SERVICES INCORPO | | | SCAC4 |
| 953 | IESS | ITECH ENVIRONMENTAL SERVICES | | | SCAC4 |
| 954 | IESV | INTERNATIONAL ENVIRONMENTAL SERVICE | | | SCAC4 |
| 955 | IESW | IMPERIAL EAGLE SHIPPING LLC | | | SCAC4 |
| 956 | IESX | Alliant Energy | added 4/2000; 7/2000-7/2005 | | NAKINA |
| 957 | IESX | IES Utilities, Inc. | added 1/1996; eliminated 4/2000 | | NAKINA |
| 958 | IESX | Iowa Southern Utilities Co. | eliminated 1/1996 | | NAKINA |
| 959 | IESX | IESX Corp. | added 7/1981; eliminated 10/1987 | | NAKINA |
| 960 | IESX | Ivan E. Summa | added 4/1974; 1/1975-1/1980; eliminated 7/1981 | | NAKINA |
| 961 | IESX | Ivan E. Summa | added 4/74; 1/75-1/80; eliminated 7/81 | | NRHS |
| 962 | IESX | IESX Corp. | added 7/81; eliminated 10/87 | | NRHS |
| 963 | IESX | Iowa Southern Utilities Co. | eliminated 1/96 | | NRHS |
| 964 | IESX | IES Utilities, Inc. | added 1/96; eliminated 4/2000 | | NRHS |
| 965 | IESX | Alliant Energy | added 4/2000; 7/2000 | | NRHS |
| 966 | IESX | ALLIANT ENERGY [IES UTIITIES; IOWA SOUTHERN UTILITIES; IESX CORP.; IVAN E. SUMMA] | | | PWRC |
| 967 | IESX | IESX Corporation (Alliant Energy) | | | RSRV |
| 968 | IESX | ALLIANT ENERGY | | | SCAC4 |
| 969 | IETA | INLAND EMPIRE TRANSPORT | | | SCAC4 |
| 970 | IETH | IMPCO ECOTRANS TECHNOLOGIES | | | SCAC4 |
| 971 | IETL | IMPACT ENERGY TRANSPORT LLC | | | SCAC4 |
| 972 | IETR | ISLE EDGE TRUCKING | | | SCAC4 |
| 973 | IETT | | City: Istanbul | TR | TRAFFIC |
| 974 | IEVC | INGRAM EXCAVATING INC | | | SCAC4 |
| 975 | IEWD | INT | | | SCAC4 |
| 976 | IEXC | IMPORT EXPORT CONTAINER TRUCKING LO | | | SCAC4 |
| 977 | IEXE | INTERCARGO EXPRESS | | | SCAC4 |
| 978 | IEXF | INTER EXPRESS INC | | | SCAC4 |
| 979 | IEXI | INTERTRANS EXPRESS INC | | | SCAC4 |
| 980 | IEXL | INTERSTATE EXPRESS LOGISTICS CORP | | | SCAC4 |
| 981 | IEXP | IMPORT EXPORT XPRESS (I E X) | | | SCAC4 |
| 982 | IEXW | IB EXPRESS | | | SCAC4 |
| 983 | IF | Interflug Gesellschaft Fur Internationalen Flugverkehr mbH | ICAO: IFL, Callsign: Interflug, Liquidated on 07 February 1991. Last operation 30 April 1991. | DDR | AVCODES |
| 984 | IF | Italy First | ICAO: IFS, Callsign: Riviera, Designator IF* recalled by IATA. ICAO callsign changed from Italy First | I | AVCODES |
| 985 | IF | Great China Airlines | ICAO: GCA, Designator IF recalled by IATA | PRC | AVCODES |
| 986 | IF | Islas Airways | ICAO: ISW, Callsign: Pintadera, IATA Prefix: 769, Founded in 2002. Commenced operations in February 2003. Ceased operations on 15 October 2012. Designator IF reinstated by IATA | E | AVCODES |
| 987 | IF | Gulf & Caribbean Cargo, Inc d/b/a Gulf & Caribbean Air | IATA Prefix: 611, Designator 8G* recalled by IATA | USA | AVCODES |
| 988 | IF | Gulf and Caribbean Cargo, Inc. d/b/a IFL Group | ICAO: TSU, Callsign: Trans-Auto, IATA Prefix: 611, Name changed from Contract Air Cargo, Inc. | USA | AVCODES |
| 989 | IF | Fly Baghdad | ICAO: FBA, Callsign: Iraq Express, | IRQ | AVCODES |
| 990 | IF | Interfrigo | | | TRAFFIC |
| 991 | IF | Innofreight Speditions GmbH | | AT | VKM |
| 992 | IFA | Fai Airservice | Callsign: Franken-Air, Name changed to FAI Rent-a-Jet AG. ICAO callsign changed to Red Angel | D | AVCODES |
| 993 | IFA | FAI Rent-a-Jet AG | IATA: F3, Callsign: Red Angel, Designator F3* recalled by IATA. Name changed from Fai Airservice. ICAO callsign changed from Franken-Air | D | AVCODES |
| 994 | IFA | FAI Rent-a-Jet AG | Callsign: Red Angel, Designator F3* recalled by IATA. Name changed from Fai Airservice. Name changed to FAI Rent-a-Jet GmbH. ICAO callsign changed from Franken-Air | D | AVCODES |
| 995 | IFA | FAI Rent-a-Jet GmbH | Callsign: Red Angel, Designator F3* recalled by IATA. Name changed from FAI Rent-a-Jet AG and previously from Fai Airservice. ICAO callsign changed from Franken-Air | D | AVCODES |
| 996 | IFA | FAI Airservice | | | ICAO1 |
| 997 | IFA | | | D | TRAFFIC |
| 998 | IFAA | INTEGRATED FREIGHT SERVICES INC | | | SCAC4 |
| 999 | IFAQ | IVANS FURNITURE & ANTIQUES | | | SCAC4 |
| 1000 | IFB | Inter Ferry Boat | B-Cargo subsidiary fournded in 2003. | B | TRAFFIC |
