| 1 | IF | Interflug Gesellschaft Fur Internationalen Flugverkehr mbH | ICAO: IFL, Callsign: Interflug, Liquidated on 07 February 1991. Last operation 30 April 1991. | DDR | AVCODES |
| 2 | IF | Italy First | ICAO: IFS, Callsign: Riviera, Designator IF* recalled by IATA. ICAO callsign changed from Italy First | I | AVCODES |
| 3 | IF | Great China Airlines | ICAO: GCA, Designator IF recalled by IATA | PRC | AVCODES |
| 4 | 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 |
| 5 | IF | Gulf & Caribbean Cargo, Inc d/b/a Gulf & Caribbean Air | IATA Prefix: 611, Designator 8G* recalled by IATA | USA | AVCODES |
| 6 | 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 |
| 7 | IF | Fly Baghdad | ICAO: FBA, Callsign: Iraq Express, | IRQ | AVCODES |
| 8 | IF | Interfrigo | | | TRAFFIC |
| 9 | IF | Innofreight Speditions GmbH | | AT | VKM |
| 10 | IFA | Fai Airservice | Callsign: Franken-Air, Name changed to FAI Rent-a-Jet AG. ICAO callsign changed to Red Angel | D | AVCODES |
| 11 | 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 |
| 12 | 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 |
| 13 | 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 |
| 14 | IFA | FAI Airservice | | | ICAO1 |
| 15 | IFA | | | D | TRAFFIC |
| 16 | IFAA | INTEGRATED FREIGHT SERVICES INC | | | SCAC4 |
| 17 | IFAQ | IVANS FURNITURE & ANTIQUES | | | SCAC4 |
| 18 | IFB | Inter Ferry Boat | B-Cargo subsidiary fournded in 2003. | B | TRAFFIC |
| 19 | IFB | INTERFERRYBOATS NV | | BE | VKM |
| 20 | IFBN | IMPERIAL FREIGHT BROKERS INC | | | SCAC4 |
| 21 | IFBX | General Electric Rail Services Corp. | added 1/2000; 7/2000-7/2005 | | NAKINA |
| 22 | IFBX | General Electric Railcar Services Corp. | added 4/1990; 1/1994; eliminated 1/2000 | | NAKINA |
| 23 | IFBX | Indiana Farm Bureau Cooperative Association, Inc. | added 7/1979; 1/1980; eliminated 4/1990 | | NAKINA |
| 24 | IFBX | Indiana Farm Bureau Cooperative Association, Inc. | added 7/79; 1/80; eliminated 4/90 | | NRHS |
| 25 | IFBX | General Electric Railcar Services Corp. | added 4/90; 1/94; eliminated 1/2000 | | NRHS |
| 26 | IFBX | General Electric Rail Services Corp. | added 1/2000; 7/2000 | | NRHS |
| 27 | IFBX | (NATX) G. E. RAIL SERVICES [INDIANA FARM BUREAU C0-0P ASSOC.] | | | PWRC |
| 28 | IFBX | Indiana Farm Bureau Cooperative Association (GE Rail Services Corporation) | | | RSRV |
| 29 | IFBX | GENERAL ELECTRIC RAILCAR SERVICES C | | | SCAC4 |
| 30 | IFC | Indian Air Force | Callsign: Indian Air Force, | IND | AVCODES |
| 31 | IFC | Indian Air Force | | | ICAO1 |
| 32 | IFCB | INTERSTATE FREIGHT CARRIERS INC | | | SCAC4 |
| 33 | IFCF | I F C INTERNATIONAL FREIGHT CORP | | | SCAC4 |
| 34 | IFCH | INTERFRACHT CONTAINER OVERSEAS SERV | | | SCAC4 |
| 35 | IFCI | IMPORTERS FORWARDING COMPANY INC | | | SCAC4 |
| 36 | IFCL | INTEGRA FUEL CO LTD | | | SCAC4 |
| 37 | IFCX | Interstate Foods Corp. | added 10/1982; 1/1994; eliminated 10/1994; 7/2000-7/2005 (not listed) | | NAKINA |
| 38 | IFCX | Interstate Foods Corp. | added 10/82; 1/94; eliminated 10/94; 7/2000 | | NRHS |
| 39 | IFCX | INTERSTATE FOODS CORPORATION | | | PWRC |
| 40 | IFCX | Interstate Foods Corporation | | | RSRV |
| 41 | IFCX | INTERSTATE FOODS CORPORATION | | | SCAC4 |
| 42 | IFDU | INTERNATIONAL FREIGHT DRONE INC. | | USA | BIC |
| 43 | IFEA | KP Elektroavtotrans Ivano-Frankivsk | City: Ivano-Frankivsk | UA | TRAFFIC |
| 44 | IFEH | INTERNATIONAL FREIGHT EXPRESS (HK) | | | SCAC4 |
| 45 | IFES | I F EXPRESS | | | SCAC4 |
| 46 | IFF | Interfreight Forwarding Ltd. | Callsign: Interfreighter, | SUD | AVCODES |
| 47 | IFF | Interfreight Forwarding | | | ICAO1 |
| 48 | IFFE | I-44 EXPRESS INC | | | SCAC4 |
| 49 | IFFG | INTEGRITY FAST FREIGHT | | | SCAC4 |
| 50 | IFFH | INTERNATIONAL FREIGHT FORWARD | | | SCAC4 |
| 51 | IFFN | INGRAHAMS FARM LTD | | | SCAC4 |
| 52 | IFFS | IFL INTERNATIONAL FREIGHT LINES LIM | | | SCAC4 |
| 53 | IFFU | DEN HARTOGH DRY BULK LOGISTICS LTD | | GB | BIC |
| 54 | IFFU | U B C LTD | | | SCAC4 |
| 55 | IFG | Infinity Flight Group | Callsign: Infinity, | USA | AVCODES |
| 56 | IFGF | IDS FREIGHT SERVICES USA LLC | | | SCAC4 |
| 57 | IFGG | INDIGO FG & G INC | | | SCAC4 |
| 58 | IFGH | ILLINOIS FREIGHT INC | | | SCAC4 |
| 59 | IFGL | INTERNATIONAL FREIGHT & LOGISTICS I | | | SCAC4 |
| 60 | IFGN | IDS FREIGHT SERVICES USA LLC | | | SCAC4 |
| 61 | IFGO | INTELLISHIP FREIGHT SOLUTIONS | | | SCAC4 |
| 62 | IFHL | IHAUL FREIGHT LTD | | | SCAC4 |
| 63 | IFHR | INTERNATIONAL FREIGHT HANDLERS LLC | | | SCAC4 |
| 64 | IFI | Air Lift A.A.E. | Callsign: Hellas Lift, Name changed from Hyperion S.A. ICAO callsign changed | GR | AVCODES |
| 65 | IFI | Hyperion, S.A. | Callsign: Hyperion, Name changed to Air Lift A.A.E. | GR | AVCODES |
| 66 | IFI | Air Lift | | | ICAO1 |
| 67 | IFIG | INTERSTATE FLEET INC | | | SCAC4 |
| 68 | IFIT | INTEGRATED FIXTURES | | | SCAC4 |
| 69 | IFIY | INFINITY EXPRESS INC | | | SCAC4 |
| 70 | IFJC | IBARRA FLORES, JOSE CIRILO & JOSE A | | | SCAC4 |
| 71 | IFJT | IFJ TRUCKING | | | SCAC4 |
| 72 | IFKO | IFKO, FRANK JR INC | | | SCAC4 |
| 73 | IFL | IFL Group, Inc. | Callsign: Eifel, | USA | AVCODES |
| 74 | IFL | Interflug Gesellschaft Fur Internationalen Flugverkehr mbH | IATA: IF, Callsign: Interflug, Liquidated on 07 February 1991. Last operation 30 April 1991. | DDR | AVCODES |
| 75 | IFL | IFL Group | | | ICAO1 |
| 76 | IFLA | INFINITI FREIGHT LOGISTICS INC | | | SCAC4 |
| 77 | IFLC | INTER FLORIDA CONTAINER TRANSPORT I | | | SCAC4 |
| 78 | IFLF | INTERNATIONAL FASTLINE FORWARDING I | | | SCAC4 |
| 79 | IFLG | IFL GROUP INC | | | SCAC4 |
| 80 | IFLI | INTERNATIONAL FREIGHT LOGISTICS (US | | | SCAC4 |
| 81 | IFLL | INTERSTATE FURNITURE LOGISTICS LLC | | | SCAC4 |
| 82 | IFLN | IFLN SHIPPING LINE | | | SCAC4 |
| 83 | IFLT | INFLIGHT EXPRESS INC | | | SCAC4 |
| 84 | IFLU | NRS OCEAN LOGISTICS LTD. | | GB | BIC |
| 85 | IFLU | INTERFLOW | | | PWRC |
| 86 | IFLU | Interflow | | | RSRV |
| 87 | IFLU | INTERFLOW TANK CONTAINER SYSTEM LTD | | | SCAC4 |
| 88 | IFLUG | Interflug | | DDR | TRAFFIC |
| 89 | IFLW | INTERFLOW USA INC | | | SCAC4 |
| 90 | IFM | iFly S.A. | Callsign: Icopter, | GR | AVCODES |
| 91 | IFM | IFM/GRACE COACH LINES INC | | | SCAC4 |
| 92 | IFME | INFINIUM ENTERPRISES INC | | | SCAC4 |
| 93 | IFMS | INFINITY MOVING & STORAGE INC | | | SCAC4 |
| 94 | IFMU | INFINITI MARINE PTE LTD | | SGP | BIC |
| 95 | IFNY | IFS (NY) INC | | | SCAC4 |
| 96 | IFOC | INDIANA FUEL & OIL CO | | | SCAC4 |
| 97 | IFOI | INDUSTRIAL CONTAINER SERVICES CO LL | | | SCAC4 |
| 98 | IFOX | Jeffrey J. Kelling | added 1/1987; eliminated 7/1989 | | NAKINA |
| 99 | IFOX | Industrial Fuel Oil, Inc. | added 1/1981; eliminated 1/1987 | | NAKINA |
| 100 | IFOX | Industrial Fuel Oil, Inc. | added 1/81; eliminated 1/87 | | NRHS |
