| 1 | N | Verkehrs-Aktiengesellschaft Nürnberg | Real: VAG, City: Nürnberg | D | TRAFFIC |
| 2 | N&C | Nashville, Chattanooga & St. Louis Ry. | 7/1923-4/1961 | NAKINA | |
| 3 | N&C | Nashville Chattanooga & St. Louis Ry. | 4/38-4/61 | NRHS | |
| 4 | N&C | NASHVILLE, CHATTANOOGA & ST. LOUIS RWY. | PWRC | ||
| 5 | N&NE | New Orleans & Northeastern R.R. | 1/1941-7/1954 | NAKINA | |
| 6 | N&NE | New Orleans & Northeastern R.R. | Jan-52 | NRHS | |
| 7 | N&NE | NEW ORLEANS & NORTHEASTERN RAILROAD | PWRC | ||
| 8 | N&PB | Norfolk & Portsmouth Belt Line R.R. (Co.) | 8/1920-10/1966 | NAKINA | |
| 9 | N&PB | Norfolk & Portsmouth Belt Line R.R. | 4/38-10/66 | NRHS | |
| 10 | N&PB | NORFOLK & PORTSMOUTH BELT LINE RAILROAD CO. | PWRC | ||
| 11 | N&SS | The Newburgh & South Shore Ry. Co. | 8/1920-7/1936 | NAKINA | |
| 12 | N&SS | NEWBURGH & SOUTH SHORE RWY. CO. | PWRC | ||
| 13 | N&W | Norfolk and Western Ry. | 1/1941-10/1966 | NAKINA | |
| 14 | N&W | Norfolk and Western Ry. | 1/52-10/66 | NRHS | |
| 15 | N&W | NORFOLK & WESTERN RWY. | PWRC | ||
| 16 | N663 | ROCKET EXPRESS | SCAC3 | ||
| 17 | NAA | National Oceanic and Atmospheric Administration | ICAO1 | ||
| 18 | NAAB | NAAB, STEVE | SCAC3 | ||
| 19 | NAAB | NATIVE DAWN FISHING LTD | SCAC4 | ||
| 20 | NAAD | NEBRASKA ATLANTIC TRANSPORTATION IN | SCAC4 | ||
| 21 | NAAE | NOBODY AUTO TRANSPORT INC | SCAC4 | ||
| 22 | NAAF | NORTH AMERICAN TRANSPORT SERVICES L | SCAC4 | ||
| 23 | NAAF | Namibian Air Force | NAM | TRAFFIC | |
| 24 | NAAG | NORTH AMERICAN AGENCIES OF TEXAS | SCAC3 | ||
| 25 | NAAG | NORTH AMERICAN CARRIERS INC | SCAC4 | ||
| 26 | NAAR | NAVIERAS ARMAS | SCAC3 | ||
| 27 | NAAS | NORTH AMERICAN AUTO LOGISTICS LLC | SCAC4 | ||
| 28 | NAAT | NATIONAL TRANSIT LEASING CORP | SCAC3 | ||
| 29 | NAB | Mina Airline Company | ICAO1 | ||
| 30 | NABC | NATIONAL BULK CARRIERS INC | SCAC3 | ||
| 31 | NABD | NEBI AND SONS TRUCKING | SCAC4 | ||
| 32 | NABF | NORTH ATLANTIC BALTIC FREIGHT CONFE | SCAC3 | ||
| 33 | NABG | NATIONAL BAGGAGE SERVICE | SCAC3 | ||
| 34 | NABG | NAVARROS TRUCKING | SCAC4 | ||
| 35 | NABH | NEW ABILITY SHIPPING INC | SCAC4 | ||
| 36 | NABI | NAB TRUCKING CO | SCAC3 | ||
| 37 | NABK | NATIONAL BOOK CONSOLIDATORS INC | SCAC3 | ||
| 38 | NABL | N A B TRUCKING LINE CORP | SCAC3 | ||
| 39 | NABR | NORTH AMERICAN BULK TRANSPORT INC | SCAC4 | ||
| 40 | NABU | ECST CONTAINER SERVICES & TRADING GMBH. | PWRC | ||
| 41 | NABU | Ecst Container Services and Trading | RSRV | ||
| 42 | NABU | ECST EXPRESS CONTAINER SERVICES & | SCAC3 | ||
| 43 | NABU | ECST CONTAINER SERVICES & TRADING G | SCAC4 | ||
| 44 | NABV | NEW AGE BEVERAGE COMPANY | SCAC4 | ||
| 45 | NABW | NABERS SOLUTIONS LLC | SCAC4 | ||
| 46 | NABX | NARRAGANSETT BAY | PWRC | ||
| 47 | NABZ | NABISCO COMPANY | PWRC | ||
| 48 | NAC | Northern Air Cargo | IATA: NC | ICAO1 | |
| 49 | NAC | NASHVILLE & ASHLAND CITY RAILROAD CO. | PWRC | ||
| 50 | NACA | NATIONAL CARTAGE CO | SCAC3 | ||
| 51 | NACB | NORTH AMERICAN CARIBBEAN LINE LTD. | SCAC3 | ||
| 52 | NACB | National Coal Board | Real: NCB | GB | TRAFFIC |
| 53 | NACC | NORTH AMERICAN CAR CO. | PWRC | ||
| 54 | NACCO | NACCO SAS | F | TRAFFIC | |
| 55 | NACCO | NACCO GmbH | DE | VKM | |
| 56 | NACD | NORTH AMERICAN CARGO SERVICES INC | SCAC4 | ||
| 57 | NACE | NARROWS CARRIERS INC | SCAC3 | ||
| 58 | NACE | NORTH AMERICAN COMPOSITES DIV OF IN | SCAC4 | ||
| 59 | NACG | NATIONAL AIR CARGO GROUP INC | SCAC4 | ||
| 60 | NACH | NA-CHURS TRANSPORTATION INC | SCAC3 | ||
| 61 | NACI | NACAL, INC | SCAC3 | ||
| 62 | NACI | NACAL INC | SCAC4 | ||
| 63 | NACJ | NATIONAL CARGO INC | SCAC3 | ||
| 64 | NACK | N & C KOHLIG INC | SCAC3 | ||
| 65 | NACL | NACKE, CLETUS TRUCK LINE INC | SCAC3 | ||
| 66 | NACM | NORTH AMERICAN COMPENDIUMS LTD | SCAC4 | ||
| 67 | NACO | NATICK CITGO | SCAC3 | ||
| 68 | NACP | NORTH AMERICAN CARRIERS | SCAC4 | ||
| 69 | NACQ | NATIONAL AIR CARGO INC | SCAC4 | ||
| 70 | NACR | Nashville & Ashland City R.R. | added 1/1982; eliminated 10/1987; eliminated 7/1989; 1/1994-7/2005 | NAKINA | |
| 71 | NACR | Nashville & Ashland City R.R. | added 1/82; eliminated 10/87; eliminated 7/89; 1/94-7/2000 | NRHS | |
| 72 | NACR | NASHVILLE & ASHLAND CITY RAILROAD | PWRC | ||
| 73 | NACR | Nashville and Ashland City Railroad | RSRV | ||
| 74 | NACR | NASHVILLE & ASHLAND CITY RAILROAD | SCAC3 | ||
| 75 | NACS | NATIONAL COURIER SYSTEMS INC | SCAC3 | ||
| 76 | NACS | NEW ACTIVITY SHIPPING INC | SCAC4 | ||
| 77 | NACT | NATIONAL CITY TRANSFER & STORAGE | SCAC3 | ||
| 78 | NACT | NATIONAL CITY TRANSFER & STORAGE | SCAC4 | ||
| 79 | NACU | NALCO LIMITED | SCAC4 | ||
| 80 | NACV | NOBLE AMERICAS CORP | SCAC4 | ||
| 81 | NACW | NATIONAL COACH WORKS INC | SCAC3 | ||
| 82 | NACX | General Electric Rail Services Corp. | added 1/2000; 7/2000-7/2005 | NAKINA | |
| 83 | NACX | North American Chemical Co. | added 4/1991; eliminated 10/1991 | NAKINA | |
| 84 | NACX | General Electric Railcar Services Corp. | added 10/1991; 1/1994; eliminated 1/2000 | NAKINA | |
| 85 | NACX | North American Car Corp. | added 1/1976; eliminated 10/1979 | NAKINA | |
| 86 | NACX | Hooker Chemical Corp. | 4/1970; eliminated 4/1971 | NAKINA | |
| 87 | NACX | Niagara Alkali Co. (Hooker Chemical Corp.) | 10/1966 | NAKINA | |
| 88 | NACX | Hooker Chemical Corp. | added 10/1958; 4/1961-7/1965 | NAKINA | |
| 89 | NACX | Hooker Electrochemical Co. | 10/1957; eliminated 10/1958 | NAKINA | |
| 90 | NACX | Hooker Chemical Corp. | added 7/1956 | NAKINA | |
| 91 | NACX | Niagara Alkali Co. | 8/1920-7/1954; eliminated 7/1956 | NAKINA | |
| 92 | NACX | Niagara Alkali Co. | 4/38-1/52; eliminated 7/56 | NRHS | |
| 93 | NACX | Hooker Chemical Corp. | added 7/56 | NRHS | |
| 94 | NACX | Hooker Electrochemical Co. | 10/57; eliminated 10/58 | NRHS | |
| 95 | NACX | Hooker Chemical Corp. | added 10/58; 4/61-7/65 | NRHS | |
| 96 | NACX | Niagara Alkali Co. (Hooker Chemical Corp.) | Oct-66 | NRHS | |
| 97 | NACX | Hooker Chemical Corp. | 4/70; eliminated 4/71 | NRHS | |
| 98 | NACX | North American Chemical Co. | added 4/91; eliminated 10/91 | NRHS | |
| 99 | NACX | General Electric Railcar Services Corp. | added 10/91; 1/94; eliminated 1/2000 | NRHS | |
| 100 | NACX | General Electric Rail Services Corp. | added 1/2000; 7/2000 | NRHS |