| 1 | NCN | National Airlines (Chile), S.A. | IATA: N4, Callsign: National, Designator recalled by IATA | RCH | AVCODES |
| 2 | NCN | National Airlines (Chile), S.A. | Callsign: National, | RCH | AVCODES |
| 3 | NCN | Niger Air Continental | IATA: N9, Callsign: Mena, | RN | AVCODES |
| 4 | NCN | National Airlines | IATA: N4 | | ICAO1 |
| 5 | NCN | Nicon Airways | | | ICAO1 |
| 6 | NCNJ | NATIONAL CASEIN OF NEW JERSEY | | | SCAC3 |
| 7 | NCNL | NORCON LOGISTICS INC | | | SCAC4 |
| 8 | NCNO | NOCONA TRANSPORT SERVICE INC | | | SCAC4 |
| 9 | NCNP | NCN TRANSPORT INC | | | SCAC4 |
| 10 | NCNR | NORTH CENTRAL TRANSIT INC | | | SCAC3 |
| 11 | NCNS | NORTH COUNTRY NURSERY SALES | | | SCAC4 |
| 12 | NCNT | NORTH CONTINENTAL TRUCKING INC | | | SCAC3 |
| 13 | NCNT | NEW CENTURY SHIPPING & TRADING INC | | | SCAC4 |
| 14 | NCNU | GRUPO LIBRA (USA) | | | SCAC1 |
| 15 | NCNU | COMPANHIA MARITIMA NACIONAL | | | SCAC4 |
