| 2401 | INTU | INTERPOOL CONTAINER PTY., LTD. | | | PWRC |
| 2402 | INTU | Interpool Container Pty | | | RSRV |
| 2403 | INTU | INTERPOOL, INC. | | | SCAC4 |
| 2404 | INTX | Interstate Commodities Inc. | 7/2005 (not listed); added 4/2007; eliminated 7/2007 | | NAKINA |
| 2405 | INTX | *INTERNATIONAL TERMINALS | | | PWRC |
| 2406 | INTX | +INTERSTATE COMMODITIES INC. | | | PWRC |
| 2407 | INTX | INTERSTATE COMMODITIES INC | | | SCAC4 |
| 2408 | INTZ | *INTEGRATED INGREDIENTS | | | PWRC |
| 2409 | INTZ | *INTERPOOL LTD. | | | PWRC |
| 2410 | INTZ | Interpool | | | RSRV |
| 2411 | INTZ | INTERPOOL LTD. | | | SCAC4 |
| 2412 | INU | Flyguppdraget Backamo AB | Callsign: Instructor, Name changed to Prokitor Flight Training AB. | S | AVCODES |
| 2413 | INU | Prokitor Flight Training AB | Callsign: Instructor, Name changed to Vflight AB. Name changed from Flyguppdraget Backamo AB. | S | AVCODES |
| 2414 | INU | Vflight AB | Callsign: Instructor, Name changed from Prokitor Flight Training AB. Name changed from Flyguppdraget Backamo AB. | S | AVCODES |
| 2415 | INU | Flyguppdraget Backamo | | | ICAO1 |
| 2416 | INUI | INUI STEAMSHIP CO LTD | | | SCAC4 |
| 2417 | INUS | INDUSTRIAL TRANSPORTATION LLC | | | SCAC4 |
| 2418 | INV | Inversia | Callsign: Inver, | LV | AVCODES |
| 2419 | INV | Inversija | | | ICAO1 |
| 2420 | INVI | INVINCIBILTY SHIPPING CO LTD | | | SCAC4 |
| 2421 | INVL | INNER VALLEY TRANSPORT | | | SCAC4 |
| 2422 | INVO | INVCON COMPANY | | | SCAC4 |
| 2423 | INVP | INNOVATIVE TRANSPORT SYSTEMS INC | | | SCAC4 |
| 2424 | INVU | INGAS LLC | | UA | BIC |
| 2425 | INVX | Invista S.A.R.L. | 7/2005 (not listed); eliminated 4/2006; added 7/2006 | | NAKINA |
| 2426 | INVX | INVISTA S.A.R.L. | | | PWRC |
| 2427 | INVX | INVISTA S A R L | | | SCAC4 |
| 2428 | INWF | INTERWEST FREIGHT SYSTEM, INC | | | SCAC1 |
| 2429 | INWG | INNOVATIVE WORLDWIDE LOGISTICS INC | | | SCAC4 |
| 2430 | INWS | INDUSTRIAL TOOLS & SUPPLIES (WINDSO | | | SCAC4 |
| 2431 | INWY | INTER-WAY CORP. | | | SCAC4 |
| 2432 | INX | Inter Express Hava Tasimacilik A.S. | IATA: 6K, Callsign: Inter-Euro, Founded on 17 December 1999. Ceased operations on 18 November 2008. | TR | AVCODES |
| 2433 | INX | Inter Express | | | ICAO1 |
| 2434 | INX | ILLINOIS NORTHERN RAILWAY | | | PWRC |
| 2435 | INXA | INLAND TRANSPORTATION LLC | | | SCAC4 |
| 2436 | INXC | INMA EXPORT CORP | | | SCAC4 |
| 2437 | INXD | INDI TRANSPORT LTD | | | SCAC4 |
| 2438 | INXE | INTERNATIONAL EXPRESS CORP | | | SCAC4 |
| 2439 | INXI | INLAND TRANSPORT INC | | | SCAC4 |
| 2440 | INXK | INTERNATIONAL EXPRESS TRUCKING INC | | | SCAC4 |
| 2441 | INXM | INNEX AMERICA LOGISTICS INC | | | SCAC4 |
| 2442 | INXN | INNOVATIONS IN TRANSPORTATION | | | SCAC4 |
| 2443 | INXP | INTERSTATE EXPRESS INC | | | SCAC4 |
| 2444 | INXU | INOX SHIPPING LINE PTE LTD | | SGP | BIC |
| 2445 | INXU | INSULINER LIMITED | | | SCAC4 |
| 2446 | INYC | INTEGRITY COLD EXPRESS INC | | | SCAC4 |
| 2447 | INYU | Infinity Transportation Logistics | | | RSRV |
| 2448 | IO | PT Indonesian Airlines Av iapatria | ICAO: IAA, Callsign: Indo Lines, | RI | AVCODES |
| 2449 | IO | Air Paris | Marged into TAT | F | AVCODES |
| 2450 | IO | Intercontinental Pacific Airways, Inc. | ICAO: IPC, Callsign: Interpac, IATA designator changed from IS* | RP | AVCODES |
| 2451 | IO | Indochina Airlines | ICAO: IDO, Ceased opertions | K | AVCODES |
| 2452 | IO | Closed Joint Stock Company IrAero | ICAO: IAE, Callsign: IrAero, | RUS | AVCODES |
| 2453 | IOA | Iowa Airways | Callsign: Iowa Air, | USA | AVCODES |
| 2454 | IOA | GSEC Monarch and Deccan Aviation Private Limited d/b/a IndiaOne Air | IATA: I7, Callsign: India First, | IND | AVCODES |
| 2455 | IOA | Iowa Airways | | | ICAO1 |
| 2456 | IOBU | BIOCOTECH AMERICAS INC | | USA | BIC |
| 2457 | IOCA | IOC TRUCKING | | | SCAC4 |
| 2458 | IOCB | INFINITO INC | | | SCAC4 |
| 2459 | IOCC | QUEBEC NORTH SHORE & LABRADOR | | | PWRC |
| 2460 | IOCC | INDEPENDENT OIL & COAL COMPANY | | | SCAC4 |
| 2461 | IOCM | IRMAS CREATIONS | | | SCAC4 |
| 2462 | IOCP | INDEPENDENT OIL COMPANY | | | SCAC4 |
| 2463 | IOCR | The Indiana & Ohio Ry. | added 7/2005; 7/2005 | | NAKINA |
| 2464 | IOCR | The Indiana & Ohio Central R.R. | added 7/1999; 7/2000; eliminated 7/2005 | | NAKINA |
| 2465 | IOCR | The Indiana & Ohio Rail System | eliminated 7/1999 | | NAKINA |
| 2466 | IOCR | The Indiana & Ohio Central R.R., Inc. | added 1/1988; 1/1994 | | NAKINA |
| 2467 | IOCR | The Indiana & Ohio Central R.R., Inc. | added 1/88; 1/94 | | NRHS |
| 2468 | IOCR | The Indiana & Ohio Rail System | eliminated 7/99 | | NRHS |
| 2469 | IOCR | The Indiana & Ohio Central R.R. | added 7/99; 7/2000 | | NRHS |
| 2470 | IOCR | INDIANA & OHIO RAILWAY [INDIANA & OHIO CENTRAL RAILROAD, INC] | | | PWRC |
| 2471 | IOCR | Indiana and Ohio Central Railroad | | | RSRV |
| 2472 | IOCT | INTEROCEAN TRADE AND TRANSPORTATION | | | SCAC4 |
| 2473 | IOCX | Rail Enterprises, Inc. | added 10/1997; eliminated 4/1998; 7/2000-7/2005 (not listed) | | NAKINA |
| 2474 | IOCX | Illinois Oil Co. | 8/1920-1/1945 | | NAKINA |
| 2475 | IOCX | Illinois Oil Co. | Apr-38 | | NRHS |
| 2476 | IOCX | Rail Enterprises, Inc. | added 10/97; eliminated 4/98; 7/2000 | | NRHS |
| 2477 | IOCX | *ILLINOIS OIL CO.. | | | PWRC |
| 2478 | IOCX | +RAIL ENTERPRISES INCORPORATED | | | PWRC |
| 2479 | IOCX | Illinois Oil Co. (Rail Enterprises) | | | RSRV |
| 2480 | IOCX | RAIL ENTERPRISES INC (ACTING AGENT | | | SCAC4 |
| 2481 | IOCY | IOC COMPANY LLC | | | SCAC4 |
| 2482 | IOE | Island Oil Exploration Limited | Callsign: Island Oil, | STP | AVCODES |
| 2483 | IOEP | I O EXPRESS INC | | | SCAC4 |
| 2484 | IOER | Indiana & Ohio Rail System | eliminated 10/1994 | | NAKINA |
| 2485 | IOER | The Indiana & Ohio Eastern R.R., Inc. | added 1/1988; 1/1994 | | NAKINA |
| 2486 | IOER | The Indiana & Ohio Eastern R.R., Inc. | added 1/88; 1/94 | | NRHS |
| 2487 | IOER | Indiana & Ohio Rail System | eliminated 10/94 | | NRHS |
| 2488 | IOER | RETIRED 01-05-94 ATP (979) [INDIANA & OHIO EASTERN RAILROAD] | | | PWRC |
| 2489 | IOER | INTER-ONTARIO EQUIPMENT RENTAL & RE | | | SCAC4 |
| 2490 | IOF | INAER Helicopteros Off-Shore, S.A. | Callsign: Inaer Offshore, | E | AVCODES |
| 2491 | IOI | Atal Milano S.r.l. | Callsign: Atalmilano, Name changed from Atal. | I | AVCODES |
| 2492 | IOI | Atal | Callsign: Atalmilano, Name changed to Atal Milano S.r.l. | I | AVCODES |
| 2493 | IOIL | IRVING OIL LIMITED | | | SCAC4 |
| 2494 | IOLL | INDEPENDENT OPERATORS LLC | | | SCAC4 |
| 2495 | IOLU | INTECH ORGANIC LIMITED | | IND | BIC |
| 2496 | IOLU | TEXTAINER EQUIPMENT MANAGEMENT (U.S.) LTD. | | | PWRC |
| 2497 | IOLU | Textainer Equipment Management | | | RSRV |
| 2498 | IOM | Island Aviation And Travel Ltd. | Callsign: Isle Avia, | GB | AVCODES |
| 2499 | IOM | Island Aviation and Travel | | | ICAO1 |
| 2500 | IOMC | INTEROCEAN MANAGMENT CORP. | | | SCAC4 |
