| 1 | NJ | Vanguard Airlines, Inc. | ICAO: VGD, Callsign: Vanguard Air, IATA Prefix: 311, Filed for Chapter 11 and suspended all operations on 30 July 2002. Designator NJ reinstated by IATA | USA | AVCODES |
| 2 | NJ | Nordisk Aviation Products, Inc. | | USA | AVCODES |
| 3 | NJ | Aero VIP, S.A. | ICAO: AOG, Callsign: Avip, IATA Prefix: 592, Established on 15 March 1999. Commenced operations on 23 June 1999. Ceased operations in November 2010. | RA | AVCODES |
| 4 | NJ | Nordic Global Airlines Oy | ICAO: NGB, Callsign: Nordic Global, Founded on 11 April 2011. Ceased opeation on 31 May 2015. Subsidiary of Finnair Group and Neff Capital Management. | FIN | AVCODES |
| 5 | NJ | Niger Airways SA | Designator NJ recalled by IATA. | RN | AVCODES |
| 6 | NJ | Romcargo Airlines S.r.l. | ICAO: RCR, Callsign: Romcargo, IATA Prefix: 690, Name changed from Fly Sky. ICAO designator changed from FSG. | RO | AVCODES |
| 7 | NJ | Nordjyske Jernbaner A/S | 2001 - | DK | jernbanen.dk |
| 8 | NJ | Delaware and Hudson Ry. Co., Inc. | added 7/1994; 7/2000-7/2005 | | NAKINA |
| 9 | NJ | CP Rail | added 7/1992; 1/1994; eliminated 7/1994 | | NAKINA |
| 10 | NJ | Napierville Junction Ry. Co. | 1/1975-1/1980; eliminated 7/1992 | | NAKINA |
| 11 | NJ | Niagara Junction Ry. Co. | 4/1938-1/1941 | | NAKINA |
| 12 | NJ | Niagara Junction Ry. Co. | Apr-38 | | NRHS |
| 13 | NJ | Napierville Junction Ry. Co. | 1/75-1/80; eliminated 7/92 | | NRHS |
| 14 | NJ | CP Rail | added 7/92; 1/94; eliminated 7/94 | | NRHS |
| 15 | NJ | Delaware and Hudson Ry. Co., Inc. | added 7/94; 7/2000 | | NRHS |
| 16 | NJ | CP RAIL (CANADIAN PACIFIC) [DELAWARE AND HUDSON RWY; NAPIERVILLE JUNCTION RY.; NIAGARA JUNCTION RY.] | | | PWRC |
| 17 | NJ | Niagara Junction Railway (Canadian Pacific Railway) | | | RSRV |
| 18 | NJ | Napierville Junction Ry. Co. | | CDN | TRAFFIC |
| 19 | NJ | Nässjö Järnvägsmuseum | | SE | VKM |
| 20 | NJA | Sky Air Cargo Services (UK) Ltd. | Formerly Tranway Air Interbational Ltd. | GB | AVCODES |
| 21 | NJA | New Japan Aviation Co., Ltd. | Callsign: Shin Nihon, | J | AVCODES |
| 22 | NJA | New Japan Aviation | | J | TRAFFIC |
| 23 | NJAC | NANJAC TRANSPORTATION SERVICES LTD | | | SCAC3 |
| 24 | NJAC | N JOSHI TRANSPORT | | | SCAC4 |
| 25 | NJAQ | N J AMERICAN WHSE CORP | | | SCAC3 |
| 26 | NJAR | NORTH JERSEY AIR SERVICE INC | | | SCAC3 |
| 27 | NJBU | CS EURASIA LEASING (SEA) PTE LTD | | SGP | BIC |
| 28 | NJBW | NICE JEWISH BOY WITH WAREHOUSE INC | | | SCAC3 |
| 29 | NJC | Nashville Jet Charters, Inc. | Callsign: Nashville Jet, | USA | AVCODES |
| 30 | NJC | Nashville Jet Charters | | | ICAO1 |
| 31 | NJCC | NEW JERSEY CHARCOAL CO | | | SCAC3 |
| 32 | NJCI | NEW JERSEY CARTAGE CO INC | | | SCAC3 |
| 33 | NJCT | NEW JERSEY COAST TRANSFER COMPANY | | | SCAC3 |
| 34 | NJCT | North Jersey Commuter Transportation | City: New Jersey | USA | TRAFFIC |
| 35 | NJCU | NINGBO JINSHI CONTAINERS CO., LTD. | | PRC | BIC |
| 36 | NJCX | New Jersey Rail Carrier | | | RSRV |
| 37 | NJD | Norsk Jernbanedrift AS | | NO | VKM |
| 38 | NJDE | NJ DRIVERS EXPRESS CORP | | | SCAC4 |
| 39 | NJDK | Nordjyske Jernbaner A/S | 2001 - | DK | TRAFFIC |
| 40 | NJDOT | New Jersey DOT | | USA | TRAFFIC |
| 41 | NJDT | NJD TRANSPORT LLC | | | SCAC4 |
| 42 | NJDX | North American Car Corp. | added 4/1956; 10/1957-1/1975; eliminated 10/1979; 1/1980 | | NAKINA |
| 43 | NJDX | North American Car Corp. | 10/57-1/80 | | NRHS |
| 44 | NJDX | GE RAIL SERVICES {NORTH AMERICAN CAR CORP.} | | | PWRC |
| 45 | NJDX | GE Rail Services | | | RSRV |
| 46 | NJE | Netjets, Transportes Aereos, S.A. | Callsign: Skyshare, ICAO callsign changed to Fraction | P | AVCODES |
| 47 | NJE | Netjets, Transportes Aereos, S.A. | Callsign: Fraction, ICAO callsign changed from Skyshare | P | AVCODES |
| 48 | NJEC | NEW JERSEY EXPRESS CORP | | | SCAC3 |
| 49 | NJEC | NORTH JERSEY ENERGY CORP | | | SCAC4 |
| 50 | NJEI | NUTT, JOSEPH E & SON INC | | | SCAC3 |
| 51 | NJEL | NINGBO JET EXPRESS INTL FREIGHT FWD | | | SCAC4 |
| 52 | NJEN | N J ENTERPRISES LTD | | | SCAC3 |
| 53 | NJEN | NEW JERSEY NONFERROUS TRADING INC | | | SCAC4 |
| 54 | NJF | Netjets Middle East | Callsign: Sunjet, | SA | AVCODES |
| 55 | NJFK | NASH, JOHN FREDERICK | | | SCAC4 |
| 56 | NJFU | NJ FROMENT AND COMPANY LIMITED | | GB | BIC |
| 57 | NJGP | NANJING PETROLEUM TRANSPORTATION CO | | | SCAC4 |
| 58 | NJIB | NATIONWIDE JUST IN TIME FREIGHT BRO | | | SCAC4 |
| 59 | NJII | Norfolk and Western Ry. Co. | added 5/1983 | | NAKINA |
| 60 | NJII | New Jersey, Indiana & Illinois R.R. Co. | 1/1975-1/1980; eliminated 5/1983 | | NAKINA |
| 61 | NJII | New Jersey, Indiana & Illinois R.R. Co. | 1/75-1/80; eliminated 5/83 | | NRHS |
| 62 | NJII | Norfolk and Western Ry. Co. | added 5/83 | | NRHS |
| 63 | NJII | NORFOLK SOUTHERN [NORFOLK & WESTERN; NEW JERSEY, INDIANA & ILLINOIS RR.] | | | PWRC |
| 64 | NJII | New Jersey, Indiana and Illinois Railroad (Norfolk and Western Railway) | | | RSRV |
| 65 | NJIM | NEW JERSEY INTERNATIONAL MOVERS INC | | | SCAC3 |
| 66 | NJJ | Nasjet Private Aviation Co., Ltd. | | SA | AVCODES |
| 67 | NJJ | Nordjyske Jernbaner | | DK | VKM |
| 68 | NJJQ | NEVE, JAMES J | | | SCAC3 |
| 69 | NJKA | NEAL, J K AGENT | | | SCAC3 |
| 70 | NJLC | NOBLE JUICES LLC | | | SCAC4 |
| 71 | NJLI | NICHOLSON, J LAURANCE & SON INC | | | SCAC3 |
| 72 | NJLK | NEW JERSEY LINK INC | | | SCAC3 |
| 73 | NJLL | NEW JERSEY LOGISTICS LLC | | | SCAC4 |
| 74 | NJLN | N & J LOGISTICS INC | | | SCAC4 |
| 75 | NJLT | NJ LOGISTICS CORP | | | SCAC4 |
| 76 | NJM | Northern Jet Management, Inc. | Callsign: Northern Jet, | USA | AVCODES |
| 77 | NJM | Nynäshamns Järnvägsmuseum | | SE | VKM |
| 78 | NJMA | NEW JERSEY MOTOR FREIGHT | | | SCAC4 |
| 79 | NJMO | N J MOTOR TRANSIT CORP | | | SCAC3 |
| 80 | NJMT | NEALY, JAMES M TRUCKING CO | | | SCAC3 |
| 81 | NJMX | NEW JERSEY MARINE TERMINALS | | | PWRC |
| 82 | NJNT | N J N TRANSPORT INC | | | SCAC4 |
| 83 | NJOL | NORTH JERSEY OIL | | | SCAC4 |
| 84 | NJOR | NAVAJO REFINING COMPANY | | | SCAC3 |
| 85 | NJPQ | NAVAS, JOHN PRODUCE COMPANY | | | SCAC3 |
| 86 | NJPT | NOONAN, J P TRANSPORTATION INC | | | SCAC3 |
| 87 | NJPT | NOONAN, J P TRANSPORTATION INC | | | SCAC4 |
| 88 | NJR | Norjet, S.A. de C.V. | Callsign: Norjet, | MEX | AVCODES |
| 89 | NJRC | New Jersey Rail Carrier LLC | 7/2005 | | NAKINA |
| 90 | NJRC | NEW JERSEY RAIL CARRIER LLC | | | PWRC |
| 91 | NJRC | New Jersey Rail Carrier | | | RSRV |
| 92 | NJRC | NEW JERSEY RAIL CARRIER LLC | | | SCAC4 |
| 93 | NJRH | NICHOLAS, J R HAULING | | | SCAC4 |
| 94 | NJRM | NASH, J R MOVING & STORGE COMPANY | | | SCAC3 |
| 95 | NJRM | NASH, J R MOVING & STORAGE | | | SCAC4 |
| 96 | NJRX | NEW JERSEY RAIL CARRIER LLC | | | PWRC |
| 97 | NJRX | NEW JERSEY RAIL CARRIER LLC | | | SCAC4 |
| 98 | NJRX | North Jersey Rail Leasing | | USA | TRAFFIC |
| 99 | NJS | National Jet Systems Pty. Ltd. | IATA: NC, Callsign: National Jet, Name changed to National Jet Systems Pty. Ltd. t/a Cobham Aviation Services Australia - Airline Services w.e.f. 13 May 2009. Designator NC reinstated by IATA | AUS | AVCODES |
| 100 | NJS | Cobham Aviation Services Australia | IATA: NC, Name changed from National Jet Systems Pty. Ltd. t/a Cobham Aviation Services Australia - Airline Services w.e.f. 13 May 2009. Designator NC recalled by IATA | AUS | AVCODES |
