| 401 | NAMU | NEDERLANDSE AARDOLIE MAATSCHAPPIJ B | | | SCAC3 |
| 402 | NAMU | CARAVAN ENGINEERED STRUCTURE INC | | | SCAC4 |
| 403 | NAMV | NATIONAL MOVERS CO INC | | | SCAC3 |
| 404 | NAMV | NORTH AMERICAN MAILING SERVICES SRL | | | SCAC4 |
| 405 | NAMW | NATIONAL VAN LINES INC | | | SCAC3 |
| 406 | NAMX | NAMX Leasing Co. | added 10/1978; 1/1980-7/2005 | | NAKINA |
| 407 | NAMX | National Ammonia Co. | added 7/1978; eliminated 10/1978 | | NAKINA |
| 408 | NAMX | Tank Car Corp. of America | 1/1941-7/1954; eliminated 4/1956 | | NAKINA |
| 409 | NAMX | North American Trading & Import Co. | 7/1930-4/1938 | | NAKINA |
| 410 | NAMX | North American Trading & Import Co. | Apr-38 | | NRHS |
| 411 | NAMX | Tank Car Corp. of America | Jan-52 | | NRHS |
| 412 | NAMX | National Ammonia Co. | added 7/78; eliminated 10/78 | | NRHS |
| 413 | NAMX | NAMX Leasing Co. | added 10/78; 1/80-7/2000 | | NRHS |
| 414 | NAMX | *NORTH AMERICAN TRADING & IMPORT CO. | | | PWRC |
| 415 | NAMX | +NAMX LEASING COMPANY [TANK CAR CORP of AMERICA] | | | PWRC |
| 416 | NAMX | NAMX Leasing | | | RSRV |
| 417 | NAMX | NAMX LEASING COMPANY | | | SCAC4 |
| 418 | NAMY | NEW AMITY SHIPPING INC | | | SCAC4 |
| 419 | NAN | National Airlines, Inc. | IATA: N7, Callsign: Nation Air, IATA Prefix: 007, Ceased operations on 06 November 2002. | USA | AVCODES |
| 420 | NAN | Norwegian Air Norway AS | IATA: DH, Callsign: Norship, | N | AVCODES |
| 421 | NAN | National Airlines | | | ICAO1 |
| 422 | NAN | Nankai Electric Railway Co., Ltd. | | J | TRAFFIC |
| 423 | NANA | NATIONAL NICKEL ALLOY CORP | | | SCAC3 |
| 424 | NANB | NOVEDADES ANEL | | | SCAC4 |
| 425 | NANBU | Nanbu Bus | | J | TRAFFIC |
| 426 | NANC | NANCE AND COLLUMS, INC | | | SCAC3 |
| 427 | NANCY | Compagnie Générale Française des Transports et Entreprises | Real: STAN, City: Nancy, The company managed public transport networks in several French cities. | F | TRAFFIC |
| 428 | NANGOK | Nangoku Kotsu | City: Kagoshima | J | TRAFFIC |
| 429 | NANJ | Nanjing Metro | | PRC | TRAFFIC |
| 430 | NANM | NATIONAL MOVERS CORPORATION | | | SCAC3 |
| 431 | NANSYUB | Nansyu Bus | | J | TRAFFIC |
| 432 | NANU | NAVIERA LAVINEL | | | SCAC3 |
| 433 | NANX | National Aniline Division, Allied Chemical Corp. | added 7/1958; 4/1961; eliminated 7/1964 | | NAKINA |
| 434 | NANX | National Aniline Division, Allied Chemical & Dye Corp. | 1/1952-10/1957; eliminated 7/1958 | | NAKINA |
| 435 | NANX | National Aniline Division, Allied Chemical & Dye Corp. | 1/52-10/57; eliminated 7/58 | | NRHS |
| 436 | NANX | National Aniline Division, Allied Chemical Corp. | added 7/58; 4/61; eliminated 7/64 | | NRHS |
| 437 | NANX | NATIONAL ANALINE DIV., ALLIED CHEMICAL CORP. | | | PWRC |
| 438 | NANY | NANCY TRANSPORTATION INC | | | SCAC3 |
| 439 | NAO | North American Airlines, Inc. | IATA: NA, Callsign: North American, IATA Prefix: 455, Founded in 1989. Ceased operations on 07 June 2014. Designator NA reinstated by IATA. IATA designator changed from XG | USA | AVCODES |
| 440 | NAO | North American Airlines, Inc. | IATA: XG, Callsign: North American, IATA designator changed to NA | USA | AVCODES |
| 441 | NAOD | NORTH AMERICAN TOOL & DIE | | | SCAC4 |
| 442 | NAOL | NATIVE OILFIELD SERVICES LLC | | | SCAC4 |
| 443 | NAOM | NAOMIS WORLD TRAVEL SERVICE INC | | | SCAC3 |
| 444 | NAOR | NAC CORPORATION | | | SCAC3 |
| 445 | NAOS | NAOS COMPANIA ARMADORA S A | | | SCAC3 |
| 446 | NAP | Napier Air Service, Inc. | Callsign: Napier, | USA | AVCODES |
| 447 | NAP | Napier Air Service Inc | | | ICAO1 |
| 448 | NAP | The Narragansett Pier R.R. Co., Inc. | 1/1975-1/1980; eliminated 10/1986; added 10/1987; eliminated 7/1989; 1/1994-7/2005 | | NAKINA |
| 449 | NAP | The Narragansett Pier R.R. Co., Inc. | 1/75-1/80; eliminated 10/86; added 10/87; eliminated 7/89; 1/94-7/2000 | | NRHS |
| 450 | NAP | NARRAGANSETT PIER RAILROAD CO. | | | PWRC |
| 451 | NAP | Narragansett Pier Railroad | | | RSRV |
| 452 | NAP | Fábrica Nitrato de Amónio de Portugal, S.A. | | PT | VKM |
| 453 | NAPA | NAPA CHARTER LINES | | | SCAC3 |
| 454 | NAPA | NAPA CHARTER LINES | | | SCAC4 |
| 455 | NAPB | NATIONAL PIGGYBACK CINCINNATI INC | | | SCAC3 |
| 456 | NAPC | NEWMAN AND PEMBERTON CORPORATION | | | SCAC3 |
| 457 | NAPE | NAPIER, ROBERT C, TRUCKING, INC | | | SCAC3 |
| 458 | NAPE | NAPOLEON EXPRESS LTD | | | SCAC4 |
| 459 | NAPK | NATIONAL PARK CONCESSIONS INC | | | SCAC3 |
| 460 | NAPL | NAPOLITANO, G TRUCKING CORP | | | SCAC3 |
| 461 | NAPL | NEVADO ARTISTIC PLASTER LTD | | | SCAC4 |
| 462 | NAPN | NATIONAL AUTOMATIC PIPELINE OPERATO | | | SCAC3 |
| 463 | NAPO | NAPOGA TRILLIUM TRANSPORT | | | SCAC4 |
| 464 | NAPOLI | Azienda Napoletana Mobilitá SPA. | Real: ANM, City: Napoli | I | TRAFFIC |
| 465 | NAPP | NAP & PAULS BOAT TRANSPORT LTD | | | SCAC3 |
| 466 | NAPP | NAP & PAULS BOAT TRANSPORT LTD | | | SCAC4 |
| 467 | NAPQ | NAPLES TRUCKING COMPANY | | | SCAC3 |
| 468 | NAPR | NAPORANO IRON & METAL CO | | | SCAC3 |
| 469 | NAPS | NEWSOME, A P & SONS | | | SCAC4 |
| 470 | NAPT | NAPPI TRUCKING CORPORATION | | | SCAC3 |
| 471 | NAPU | NAVIERA PACIFICO CA | | | SCAC3 |
| 472 | NAPU | NAVIERA PACIFICO CA | | | SCAC4 |
| 473 | NAPV | NAZARETH TRANSPORT SERVICES | | | SCAC3 |
| 474 | NAPW | NAVIERA AMAZONICA PERUANA S A | | | SCAC3 |
| 475 | NAPW | NAVIERA AMAZONICA PERUANA S A | | | SCAC4 |
| 476 | NAPX | North American Plastics, Inc. | added 10/1995; 7/2000-7/2005 | | NAKINA |
| 477 | NAPX | North American Plastics, Inc. | added 10/95; 7/2000 | | NRHS |
| 478 | NAPX | NORTH AMERICAN PLASTICS INCORPORATED | | | PWRC |
| 479 | NAPX | North American Plastics | | | RSRV |
| 480 | NAQA | NACA (VANGUARD LOGISTICS SERVICES) | | | SCAC4 |
| 481 | NAR | Air Continental, Inc. | Callsign: Night Air, | USA | AVCODES |
| 482 | NAR | Aviacion Nacional de Nicaragua, S.A. (Nicaragua Airways) | Callsign: Nica Airways, | NIC | AVCODES |
| 483 | NAR | Air Continental Inc | | | ICAO1 |
| 484 | NAR | Canadian National Rys. | added 4/1981; 1/1994-7/2005 | | NAKINA |
| 485 | NAR | Northern Alberta Rys. Co. | 7/1930-10/1966 & 1/1975-1/1980; eliminated 4/1981 | | NAKINA |
| 486 | NAR | Northern Alberta Rys. Co. | 4/38-10/66 & 1/75-1/80; eliminated 4/81 | | NRHS |
| 487 | NAR | Canadian National Rys. | added 4/81; 1/94-7/2000 | | NRHS |
| 488 | NAR | CANADIAN NATIONAL RWY [NORTHERN ALBERTA RAILWAYS] | | | PWRC |
| 489 | NAR | Northern Alberta Railway (Canadian National Railway) | | | RSRV |
| 490 | NAR | Northern Alberta Railways | | CDN | TRAFFIC |
| 491 | NARA | NAVIERA RAMA S A | | | SCAC3 |
| 492 | NARA | NARDELLI BROS INC | | | SCAC4 |
| 493 | NARA | Nara Electric Railway | | J | TRAFFIC |
| 494 | NARF | N A R CORPORATION | | | SCAC3 |
| 495 | NARF | NARFA FARMS LTD | | | SCAC4 |
| 496 | NARG | NORTH AMERICAN REFRIGERATED CARRIER | | | SCAC4 |
| 497 | NARH | N & R TRUCKING | | | SCAC3 |
| 498 | NARJ | NARANJO TRUCKING LLC | | | SCAC4 |
| 499 | NARKE | Newark & Elizabeth Independent Bus Operator | | USA | TRAFFIC |
| 500 | NARKWO | Newark & West Orange IBOA | | USA | TRAFFIC |
