| 501 | NARL | NARA TRANSPORT LIMITED | | | SCAC4 |
| 502 | NARM | N A R M TRANSPORTATION BROKERAGE | | | SCAC3 |
| 503 | NARN | NARTRON CORP | | | SCAC3 |
| 504 | NARO | NARO ENTERPRISES INC | | | SCAC3 |
| 505 | NARP | NORTHWEST ARKANSAS PAPER CO INC | | | SCAC3 |
| 506 | NARR | NORTH AMERICAN TRANSPORTATION INC | | | SCAC3 |
| 507 | NARR | NAVARRO ZUNIGA, ITZEL ANDREA | | | SCAC4 |
| 508 | NARS | NOFFS ATLANTIC RELOCATION SYSTEMS | | | SCAC4 |
| 509 | NART | NATIONAL RETAIL TRANSPORTATION, INC | | | SCAC3 |
| 510 | NART | NATIONAL RETAIL TRANSPORTATION INC | | | SCAC4 |
| 511 | NARU | MT CONTAINER GMBH | | D | BIC |
| 512 | NARV | NORTH ARLINGTON VAN LINES INC | | | SCAC3 |
| 513 | NARX | NORCHEM, Inc. | 1/1994-7/2000 (not listed) | | NAKINA |
| 514 | NARX | North American Royalties, Inc. | added 1/1978; 1/1980; eliminated 10/1982 | | NAKINA |
| 515 | NARX | North American Refining Co. (North American Oil & Refining Corp.) | 8/1920-7/1923 | | NAKINA |
| 516 | NARX | North American Royalties, Inc. | added 1/78; 1/80; eliminated 10/82 | | NRHS |
| 517 | NARX | NORCHEM, Inc. | 1/94-7/2000 | | NRHS |
| 518 | NARX | *NORTH AMERICAN OIL & REFINING CORP. [NORTH AMERICAN REFINING CO.] | | | PWRC |
| 519 | NARX | *NORTH AMERICAN ROYALTIES, INC. | | | PWRC |
| 520 | NARX | *NORCHEM INC. | | | PWRC |
| 521 | NARY | NARAYANS TRUCKING INC | | | SCAC4 |
| 522 | NARZ | NORTH ALABAMA RAILROAD MUSEUM | | | PWRC |
| 523 | NAS | Northeast Aviation Services Ltd. | | GB | AVCODES |
| 524 | NAS | Nasair Air Service | IATA: UE, Callsign: Nasairways, IATA Prefix: 770, | ER | AVCODES |
| 525 | NAS | Nasair | IATA: UE | | ICAO1 |
| 526 | NASA | NORTH AMERICAN SHIPPING | | | SCAC3 |
| 527 | NASA | NORTH AMERICAN SHIPPING AGENCIES IN | | | SCAC4 |
| 528 | NASA | | | USA | TRAFFIC |
| 529 | NASB | NASH, B B | | | SCAC3 |
| 530 | NASB | NEW ACCORD SHIPPING INC | | | SCAC4 |
| 531 | NASC | NORDAMERIK | | | SCAC4 |
| 532 | NASD | NATIONAL ARCHERY SUPPLY INC | | | SCAC4 |
| 533 | NASE | NASSAR EXPRESS | | | SCAC3 |
| 534 | NASF | NASH FUELS TRANSPORT INC | | | SCAC4 |
| 535 | NASG | NATIONAL SHIPPING AGENCY CORPORATIO | | | SCAC3 |
| 536 | NASH | NASHUA MOTOR EXPRESS, INC | | | SCAC3 |
| 537 | NASH | NASHUA MOTOR EXPRESS, INC | | | SCAC4 |
| 538 | NASI | NEW ADVANCE SHIPPING INC | | | SCAC4 |
| 539 | NASL | NORTH & SOUTH LINES INCORPORATED | | | SCAC3 |
| 540 | NASN | NASON'S DELIVERY, INC | | | SCAC3 |
| 541 | NASP | NASI, INC | | | SCAC3 |
| 542 | NASP | NAUTICA SHIPHOLDING LTD | | | SCAC4 |
| 543 | NASQ | NEATNESS AUTO SALES | | | SCAC4 |
| 544 | NASR | NASCAR | | | SCAC4 |
| 545 | NASS | NASS TRUCK LINES INC | | | SCAC3 |
| 546 | NAST | NAVISTAR S A PANAMA | | | SCAC4 |
| 547 | NASU | NASSAU LEASING CORPORATION | | | SCAC3 |
| 548 | NASU | NASSAU LEASING CORPORATION | | | SCAC4 |
| 549 | NASW | NASSAU WORLD WIDE MOVERS INC | | | SCAC3 |
| 550 | NASX | NASA RAILROAD | | | PWRC |
| 551 | NASX | NASA Railroad | | | RSRV |
| 552 | NASZ | NASSAU LEASING CORPORATION | | | SCAC3 |
| 553 | NAT | North Atlantic Air, Inc. | Callsign: Mass Air, | USA | AVCODES |
| 554 | NAT | North Atlantic Air Inc | | | ICAO1 |
| 555 | NAT | National Air Transport | The predecessor of United Airlines | USA | TRAFFIC |
| 556 | NATAN | Firma "Natan" Bogdan Głogowski | City: Płaza | PL | TRAFFIC |
| 557 | NATB | NATIONAL TRUCKING & MOVING CO | | | SCAC3 |
| 558 | NATB | BAT Group | | GB | TRAFFIC |
| 559 | NATC | NATCO INC | | | SCAC3 |
| 560 | NATD | NATURAL FREIGHT LTD NEW YORK NY | | | SCAC4 |
| 561 | NATE | NATIONWIDE TRUCK LINES INC | | | SCAC3 |
| 562 | NATE | N A T S NURSERY LTD | | | SCAC4 |
| 563 | NATF | NORTH AMERICA TRAFFIC INC | | | SCAC4 |
| 564 | NATG | NATIONWIDE MAGAZINE & BOOK DISTRIBU | | | SCAC3 |
| 565 | NATG | NATIONWIDE MAGAZINE & BOOK DISTRIBU | | | SCAC4 |
| 566 | NATH | NATIVE AMERICAN TRUCKING INC | | | SCAC3 |
| 567 | NATH | NATIVE AMERICAN TRUCKING INC | | | SCAC4 |
| 568 | NATI | NORDANG, ART TRUCKING INC | | | SCAC3 |
| 569 | NATI | NORDANG, ART TRUCKING INC | | | SCAC4 |
| 570 | NATJ | NATIONAL CITY TRUCK RENTAL | | | SCAC3 |
| 571 | NATJ | NATIONAL TRANSPORT INC | | | SCAC4 |
| 572 | NATK | NORTH AMERICAN TRANSPORTATION LLC | | | SCAC4 |
| 573 | NATL | NATIONAL TRUCKING CO OF LOS ANGELES | | | SCAC3 |
| 574 | NATL | NATIONAL OIL | | | SCAC4 |
| 575 | NATL | National | | GB | TRAFFIC |
| 576 | NATM | NATALIE MARITIME LTD | | | SCAC4 |
| 577 | NATN | N A T TRANSPORTATION INC | | | SCAC3 |
| 578 | NATN | N A T TRANSPORTATION INC | | | SCAC4 |
| 579 | NATO | NORTH AMERICAN TRANSPORTATION | | | SCAC3 |
| 580 | NATO | NORTH AMERICAN TANK LINE INC | | | SCAC4 |
| 581 | NATP | NEW AGE TRANSPORTATION DISTRIBUTION | | | SCAC4 |
| 582 | NATQ | NATALE FRANK INC | | | SCAC3 |
| 583 | NATQ | NATEX | | | SCAC4 |
| 584 | NATR | NATURES WONDER WHEATGRASS JUICE | | | SCAC4 |
| 585 | NATS | NATIONAL TRUCKING AND STORAGE CO IN | | | SCAC3 |
| 586 | NATS | N A T | | | SCAC4 |
| 587 | NATT | NORTH AMERICAN CARRIER GROUP LLC | | | SCAC4 |
| 588 | NATU | SHAPE | | B | BIC |
| 589 | NATU | NASSO SA | | | PWRC |
| 590 | NATU | Nasso SA | | | RSRV |
| 591 | NATU | NASSO S.A. | | | SCAC3 |
| 592 | NATU | SHAPE | | | SCAC4 |
| 593 | NATW | NATIONWIDE TRUCK BROKERS INC | | | SCAC3 |
| 594 | NATW | NATIONWIDE TRUCK BROKERS INC | | | SCAC4 |
| 595 | NATX | General Electric Rail Services Corp. | added 1/2000; 7/2000-7/2005 | | NAKINA |
| 596 | NATX | General Electric Railcar Services Corp. | added 1/1984; 1/1994; eliminated 1/2000 | | NAKINA |
| 597 | NATX | North American Car Corp. | 1/1950-1/1980; eliminated 1/1984 | | NAKINA |
| 598 | NATX | North American Tank Line (North American Car Corp.) | 1/1941-4/1947 | | NAKINA |
| 599 | NATX | North American Tank Line | 7/1937-4/1938 | | NAKINA |
| 600 | NATX | North American Tank Line (North American Car Corp.) | 7/1930-7/1935 | | NAKINA |
