| 5301 | NRO | Aero Rent JSC | | | ICAO1 |
| 5302 | NROH | NORCO | | | SCAC3 |
| 5303 | NROK | NORTHERN OKLAHOMA RAILWAY COMPANY | | | SCAC3 |
| 5304 | NRON | NOTHROP, RON | | | SCAC4 |
| 5305 | NROU | NRS OCEAN LOGISTICS LTD. | | GB | BIC |
| 5306 | NRP | Aeronord-Grup | Callsign: Aeronord, | MD | AVCODES |
| 5307 | NRP | Aeronord-Grup | | | ICAO1 |
| 5308 | NRPI | NORMAN, R & P INC | | | SCAC3 |
| 5309 | NRPK | NORPAK CORP | | | SCAC4 |
| 5310 | NRPP | NORRICK PETROLEUM PRODUCTS INC | | | SCAC4 |
| 5311 | NRPX | Northrop Corp. | added 4/1990; 1/1994; eliminated 7/1994; 7/2000-7/2005 (not listed) | | NAKINA |
| 5312 | NRPX | National Rosin Oil & Size Co. | 8/1920-7/1935 | | NAKINA |
| 5313 | NRPX | Northrop Corp. | added 4/90; 1/94; eliminated 7/94; 7/2000 | | NRHS |
| 5314 | NRPX | *NATIONAL ROSIN OIL & SIZE CO. | | | PWRC |
| 5315 | NRPX | +NORTHROP CORPORATION | | | PWRC |
| 5316 | NRPX | Northrop Corporation | | | RSRV |
| 5317 | NRR | Travelair d/b/a Nature Air | IATA: 5C, Callsign: Natureair, Operations were suspended by Costa Rica CAA on 12 January 2018. | CR | AVCODES |
| 5318 | NRR | Natureair | | | ICAO1 |
| 5319 | NRR | Nobles Rock R.R. | added 4/1994; eliminated 7/1997; added 1/2000; 7/2000-7/2005; eliminated 7/2006 | | NAKINA |
| 5320 | NRR | Nobles Rock R.R. | added 4/94; eliminated 7/97; added 1/2000; 7/2000 | | NRHS |
| 5321 | NRR | NOBLES ROCK RAILROAD | | | PWRC |
| 5322 | NRR | Nobles Rock Railroad | | | RSRV |
| 5323 | NRRA | NAVARRO FRANCO, ALFREDO | | | SCAC4 |
| 5324 | NRRC | RETIRED 04-20-92 ATP [NARAGANSETT RAILWAY CO.] | | | PWRC |
| 5325 | NRRF | NORTHERN REFRIGERATED TRANSPORTATION, INC | | | SCAC3 |
| 5326 | NRRF | NORTHERN REFRIGERATED TRANSPORTATIO | | | SCAC4 |
| 5327 | NRRM | NATIONAL RAILROAD MUSEUM | | | PWRC |
| 5328 | NRRS | NORRIS, R CO INC | | | SCAC3 |
| 5329 | NRRS | NORRIS, R CO INC | | | SCAC4 |
| 5330 | NRRX | NOBLES ROCK RAILROAD | | | PWRC |
| 5331 | NRS | Atlantic Richfield Company | Callsign: North Slope, | USA | AVCODES |
| 5332 | NRS | Norwegian Air UK Ltd. | IATA: DI, Callsign: Norworld, ICAO Callsign changed to Rednose. | GB | AVCODES |
| 5333 | NRS | Norwegian Air UK Ltd. | IATA: DI, Callsign: Rednose, Ceased operations on 01 November 2021. ICAO Callsign changed from Norworld. | GB | AVCODES |
| 5334 | NRS | Atlantic Richfield Company | | | ICAO1 |
| 5335 | NRS | Nordic Railservices GmbH | Lübeck | D | privat-bahn.de |
| 5336 | NRS | Dutch Rhine Railway Company | | NL | TRAFFIC |
| 5337 | NRS | Nordic Rail Service GmbH | | DE | VKM |
| 5338 | NRSC | NORTHERN STAR CARTAGE | | | SCAC3 |
| 5339 | NRSE | NORSEMAN ALLFOAM | | | SCAC4 |
| 5340 | NRSG | Nordic Rail Service GmbH | Real: NRS | D | TRAFFIC |
| 5341 | NRSH | NORTHSHORE TAXI | | | SCAC3 |
| 5342 | NRSH | NATIONAL RETAIL TRANSPORTATION INC | | | SCAC4 |
| 5343 | NRSI | NORCROSS TRANSFER & STORAGE INC | | | SCAC3 |
| 5344 | NRSK | NORRIS TRUCKING | | | SCAC4 |
| 5345 | NRSL | NORDCO RAIL SERVICES LLC | | | SCAC4 |
| 5346 | NrSlJ | Norra Södermanlands Järnväg | 1895 - 1931 | S | svenska-lok.se |
| 5347 | NRSM | NORSEME | | | SCAC4 |
| 5348 | NRSN | NR TRANSPORTATION INC | | | SCAC3 |
| 5349 | NRSO | NORRIS SUPPLY COMPANY INC | | | SCAC3 |
| 5350 | NRSQ | NORRIS TRANSFER & STORAGE CO INC | | | SCAC3 |
| 5351 | NRSR | NORTHSHORE TRANSPORTATION | | | SCAC3 |
| 5352 | NRSS | NORCROSS CHARTER INC | | | SCAC3 |
| 5353 | NRST | NORTHERN STATES TRUCKING INC | | | SCAC4 |
| 5354 | NRSU | NRS CORPORATION | | J | BIC |
| 5355 | NRSU | NIPPON RIKU-UN SANGYO CO. | | | PWRC |
| 5356 | NRSU | Nippon Riku-un Sangyo | | | RSRV |
| 5357 | NRSU | NIPPON RIKU-UN SANGYO CO | | | SCAC4 |
| 5358 | NRSV | NATIONWIDE RAIL SERVICES INC | | | SCAC4 |
| 5359 | NRSW | NEW RESOURCE SHIPPING INC | | | SCAC4 |
| 5360 | NRSY | NORAMCO SYSTEMS INC | | | SCAC3 |
| 5361 | NRT | Norestair, S.L. | Callsign: Norestair, | E | AVCODES |
| 5362 | NRT | Norestair | | | ICAO1 |
| 5363 | NRT | Northern Refrigerator Line, Inc. | 7/1937-1/1941 | | NAKINA |
| 5364 | NRT | Northern Tank Car Line (Northern Refrigerator Line, Inc.) | 7/1935 | | NAKINA |
| 5365 | NRT | Northern Refrigerator Line, Inc. | Apr-38 | | NRHS |
| 5366 | NRT | NORTHERN REFRIGERATOR LINE, INC. | | | PWRC |
| 5367 | NRTA | NORRIS TRANSPORT INC | | | SCAC3 |
| 5368 | NRTA | NORTH AUTO | | | SCAC4 |
| 5369 | NRTC | N E R TRANSPORT CO INC | | | SCAC4 |
| 5370 | NRTF | NORTHERN TRANSFER & STORAGE | | | SCAC3 |
| 5371 | NRTF | NRT FREIGHT CORP | | | SCAC4 |
| 5372 | NRTG | NEW RIVER TRUCKING LLC | | | SCAC4 |
| 5373 | NRTH | NORTH RIDGE TRUCKING COMPANY | | | SCAC3 |
| 5374 | NRTI | NORTHRIDGE TRUCKING CORP | | | SCAC3 |
| 5375 | NRTI | NITE RIDER TRANSPORT INC | | | SCAC4 |
| 5376 | NRTJ | NATIONAL REFRIGERATED TRUCKING LLC | | | SCAC4 |
| 5377 | NRTL | NOBACH, RANDY TRUCKING LLC | | | SCAC4 |
| 5378 | NRTM | NORTEM | | | SCAC4 |
| 5379 | NRTN | NATIONAL RETAIL TRANSPORTATION INC | | | SCAC4 |
| 5380 | NRTO | NORTHWEST AUTO PARTS | | | SCAC3 |
| 5381 | NRTP | NORFOLK TRANSPORTATION INC | | | SCAC3 |
| 5382 | NRTP | NORTON TRANSPORTATION LLC | | | SCAC4 |
| 5383 | NRTQ | NORRIS TRANSPORT LIMITED | | | SCAC3 |
| 5384 | NRTQ | NORDEN ROAD TRANSPORT | | | SCAC4 |
| 5385 | NRTR | NATIONAL RETAIL TRANSPORTATION INC | | | SCAC4 |
| 5386 | NRTT | NORTHEAST TRANSPORT INC | | | SCAC4 |
| 5387 | NRTU | NRS CORPORATION | | J | BIC |
| 5388 | NRTV | NORTHRIDGE TRAVEL SERVICE | | | SCAC3 |
| 5389 | NRTV | NATIONAL RETAIL TRANSPORTATION INC | | | SCAC4 |
| 5390 | NRTW | NORMS TOWING | | | SCAC3 |
| 5391 | NRTX | Northern Tank Car Line (Northern Refrigerator Line, Inc.) | 7/1930-1/1941 | | NAKINA |
| 5392 | NRTX | Northern Tank Car Lines (Northern Refrigerator Line, Inc.) | Apr-38 | | NRHS |
| 5393 | NRTX | NORTHERN TANK CAR LINES (NORTHERN REFRIGERATOR LINE, INC.) | | | PWRC |
| 5394 | NRTX | Music City Star | | | RSRV |
| 5395 | NRTX | REGIONAL TRANSPORTATION AUTHORITY-N | | | SCAC4 |
| 5396 | NRTX | Music City Star | Nashville | USA | TRAFFIC |
| 5397 | NRUC | ASSIGNED BY DCTL - NATL RLY UTILIZATION CORPORATION | | | PWRC |
| 5398 | NRUD | NORLUND TRUCKING | | | SCAC4 |
| 5399 | NRV | North Vancouver Air | IATA: VL, Callsign: Norvan, Name changed to International Express Air Charter Ltd. Designator VL* reinstated by IATA | CDN | AVCODES |
| 5400 | NRV | North Vancouver Airlines | | | ICAO1 |
