| 801 | IDNS | INDIAN SPRINGS TRUCK LINES | | | SCAC4 |
| 802 | IDO | Indochina Airlines | IATA: IO, Ceased opertions | K | AVCODES |
| 803 | IDOD | ID-OD LTD | | | SCAC4 |
| 804 | IDOX | U.S. Dept. of Energy, Idaho Operations Office | added 10/2000; eliminated 10/2004; 7/2005 (not listed) | | NAKINA |
| 805 | IDOX | Lockheed Idaho Technologies Co. | added 4/1995; 7/2000; eliminated 10/2000 | | NAKINA |
| 806 | IDOX | EG&G Idaho, Inc. | added 4/1987; 1/1994; eliminated 4/1995 | | NAKINA |
| 807 | IDOX | EG&G Idaho, Inc. | added 4/87; 1/94; eliminated 4/95 | | NRHS |
| 808 | IDOX | Lockheed Idaho Technologies Co. | added 4/95; 7/2000; eliminated 10/2000 | | NRHS |
| 809 | IDOX | U.S. Dept. of Energy, Idaho Operations Office | added 10/2000 | | NRHS |
| 810 | IDOX | *MAXON CORPORATION | | | PWRC |
| 811 | IDOX | +US DEPARTMENT OF ENERGY, IDAHO OPERATIONS OFFICE | | | PWRC |
| 812 | IDOX | United States Department of Energy Idaho Operations Office | | | RSRV |
| 813 | IDOX | US DEPARTMENT OF ENERGY IDAHO OPERA | | | SCAC4 |
| 814 | IDP | Independent Air Freighters PTY Ltd. | Callsign: Independent, | AUS | AVCODES |
| 815 | IDP | Independent Air Freighters | | | ICAO1 |
| 816 | IDPC | INDEPENDENT COURIERS LTD | | | SCAC4 |
| 817 | IDPD | INDEPENDENT OIL COMPANY | | | SCAC4 |
| 818 | IDPN | INDEPENDENT TRAFFIC MANAGEMENT | | | SCAC4 |
| 819 | IDPS | INDUSTRIAL PLANT SERVICE | | | SCAC4 |
| 820 | IDPT | IDEAL PRODUCTS DISTRIBUTING | | | SCAC4 |
| 821 | IDPV | INTERCIONAL DE PRODUCTOS Y SEMILLAS | | | SCAC4 |
| 822 | IDPY | INTERNACIONAL DE PRODUCTOS Y SEMILL | | | SCAC4 |
| 823 | IDR | Indicator Company | Callsign: Indicator, | H | AVCODES |
| 824 | IDR | Evelop Airlines Dominicana, S.A. d/b/a Iberojet | Callsign: Mangu, | DOM | AVCODES |
| 825 | IDR | Indicator Company | | | ICAO1 |
| 826 | IDRK | IDR TRUCKING | | | SCAC4 |
| 827 | IDRL | INDUSTRY ORNAMENTAL IRON | | | SCAC4 |
| 828 | IDRT | INSELL, D R TRANSPORT INC | | | SCAC4 |
| 829 | IDS | IDS Aircraft Ltd. d/b/a I.D.S. Heathrow Exective Jets | IATA: IS, Callsign: Fanjet, Name changed from IDS Aircraft Ltd. | GB | AVCODES |
| 830 | IDS | IDS Aircraft Ltd. | IATA: IS, Callsign: IDS, Name changed to IDS Aircraft Ltd. d/b/a I.D.S. Heathrow Exective Jets | GB | AVCODES |
| 831 | IDS | IDS - Inženýrské a dopravní stavby Olomouc a.s. | | CZ | VKM |
| 832 | IDSA | INTERNATIONAL DIRECTIONAL SERVICES | | | SCAC4 |
| 833 | IDSB | IMMEDIATE DELIVERY SYSTEMS LLC | | | SCAC4 |
| 834 | IDSC | IDS CARGO a. s | | CZ | TRAFFIC |
| 835 | IDSC | IDS CARGO a. s. | | CZ | VKM |
| 836 | IDSE | INTER URBAN DELIVERY SERVICE LTD | | | SCAC4 |
| 837 | IDSJ | IIF DATA SOLUTIONS INC | | | SCAC4 |
| 838 | IDSL | INTERMODAL SERVICES OF LAREDO L L C | | | SCAC4 |
| 839 | IDSM | INDUSTRIAL MACHINE TRANSPORT INC | | | SCAC4 |
| 840 | IDSN | INDUSTRIAL DISTRIBUTION SERVICE INC | | | SCAC4 |
| 841 | IDSQ | IDS EXPRESS INC | | | SCAC4 |
| 842 | IDSR | INDUSTRIAL MAINTENANCE & SERVICE CORPORATION | | | SCAC1 |
| 843 | IDSR | INDUSTRIAL MAINTENANCE & SERVICE CO | | | SCAC4 |
| 844 | IDSS | IDS TRANSPORTATION SERVICES INC (N/ | | | SCAC4 |
| 845 | IDST | IDS TRUCKING INC | | | SCAC4 |
| 846 | IDSU | SWIRE OILFIELD SERVICES LTD | | GB | BIC |
| 847 | IDSU | SWIRE OILFIELD SERVICES LTD | | | SCAC4 |
| 848 | IDSW | IDC DENIZCILIK SANAYI VE TICARET AS | | | SCAC4 |
| 849 | IDSZ | INDUSTRIAL DISTRIBUTION SERVICE, INC. | | | PWRC |
| 850 | IDSZ | Industrial Distribution Service | | | RSRV |
| 851 | IDSZ | INDUSTRIAL DISTRIBUTION SERVICE, IN | | | SCAC4 |
| 852 | IDT | Illinois Department of Transportation | Callsign: Idot, | USA | AVCODES |
| 853 | IDTG | INDUSTRIAL TRUCKING GROUP INC | | | SCAC4 |
| 854 | IDTI | IDEAL DRAIN TILE LIMITED | | | SCAC4 |
| 855 | IDTO | INDUSTRIAL CONNECTIONS INC | | | SCAC4 |
| 856 | IDTR | IDA-TRAN FREIGHT SYSTEMS, INC | | | SCAC1 |
| 857 | IDTS | INDUSTRIAL TRANSPORT SERVICES LLC | | | SCAC4 |
| 858 | IDTU | ODYSSEY FOODTRANS | | USA | BIC |
| 859 | IDTU | Hawaii Intermodal Tank Transport | | | RSRV |
| 860 | IDTU | HAWAII INTERMODAL TANK TRANSPORT LL | | | SCAC4 |
| 861 | IDTV | INDUSTRIAL TRANSPORT INC | | | SCAC4 |
| 862 | IDTX | INDIANA DINNER TRAIN | | | PWRC |
| 863 | IDU | Air Industria S.p.A. | IATA: 7Y, Callsign: Industria, Suspended operations during 2003. | I | AVCODES |
| 864 | IDVB | IMPORTADORA DE VEHICULOS BLINDADOS | | | SCAC4 |
| 865 | IDX | PT. Indonesia AirAsia Extra | IATA: XT, Callsign: Red Phoenix, Ceased operations on 14 January 2019. Subsidary of AirAsia X Berhad. | RI | AVCODES |
| 866 | IDX | U.S. Industrial Alcohol Co. | 8/1920-7/1935 | | NAKINA |
| 867 | IDX | U.S. INDUSTRIAL ALCOHOL CO. | | | PWRC |
| 868 | IDXC | INDIANA TRANSPORT LLC | | | SCAC4 |
| 869 | IDXI | IDEA TRANSPORT INC | | | SCAC4 |
| 870 | IDXL | INTERIDE TRANSPORT LC | | | SCAC4 |
| 871 | IDXS | INDUSTRIAL EXPRESS SERVICE INC | | | SCAC4 |
| 872 | IDXV | IDEAL TRANSPORT SERVICE LTD | | | SCAC4 |
| 873 | IDYE | INDY EXPEDITING NATIONWIDE INC | | | SCAC4 |
| 874 | IDYT | INDY EXPRESS TRUCKING INC | | | SCAC4 |
| 875 | IE | Solomon Airlines | ICAO: SOL, Callsign: Solomon, IATA Prefix: 193, | SOL | AVCODES |
| 876 | IE | Solomon Islands Airways Ltd. | Callsign: Solair, IATA Prefix: 193, | SOL | AVCODES |
| 877 | IE | Iarnrod Eireann (Coras Iompair Eireann) | | IE | VKM |
| 878 | IEA | Intermediacion Aerea S.L., Compania Aerea t/a InterMed | Callsign: Intermed, Established in 1997. Ceased operations in 2005. | E | AVCODES |
| 879 | IEA | Inter European Airways Ltd. | IATA: IP, Callsign: Aspro, Merged into Airtours International Airways Ltd on 02 September 1993. | GB | AVCODES |
| 880 | IEA | Inland Empire Airlines, Inc. | Callsign: Inland Empire, | USA | AVCODES |
| 881 | IEAF | Imperial Ethiopian Air Force | | ETH | TRAFFIC |
| 882 | IEAM | INVENTURE ENGINEERING AND | | | SCAC4 |
| 883 | IEAR | INFINITE ENTERPRISES INC | | | SCAC4 |
| 884 | IEAU | SEACO SRL | | BDS | BIC |
| 885 | IEAU | INTERMODAL EQUIPMENT ASSOCIATES | | | PWRC |
| 886 | IEAU | Intermodal Equipment Associates | | | RSRV |
| 887 | IEAU | CRONOS CONTAINERS LTD | | | SCAC4 |
| 888 | IEC | Iowa Chicago and Eastern R.R. Corp. | added 10/2002 | | NAKINA |
| 889 | IEC | EASTERN RAILROAD CORP. | | | PWRC |
| 890 | IECA | INTELLIGENT ENGINEERING (CANADA) LI | | | SCAC4 |
| 891 | IECC | IMPERIAL EVERGREEN CASKET CORPORATI | | | SCAC4 |
| 892 | IECD | IDEAL DELIVERIES INC | | | SCAC4 |
| 893 | IECD | ELECTROCENTRALE SA DEVA | | RO | VKM |
| 894 | IECL | INTERSTATE EXPRESS CARRIER LIMITED | | | SCAC4 |
| 895 | IECR | INTER ELECTRONICS CORP | | | SCAC4 |
| 896 | IECT | INTERNATIONAL PAPER (SPRINGHILL CON | | | SCAC4 |
| 897 | IECU | MARIANAS GAS CORPORATION DBA ISLAND EQUIPMENT CO | | GUM | BIC |
| 898 | IECU | ISLAND EQUIPMENT CO | | | SCAC4 |
| 899 | IECV | ITOCHU ENEX CO LTD | | | SCAC4 |
| 900 | IEDG | ISLE EDGE TRUCKING INC | | | SCAC4 |
