| 1 | NPL | Air Nepal International Pvt. Ltd. | IATA: SZ, Callsign: Air Nepal, IATA Prefix: 855, All of its flights were suspended from 22 December 2005. | NEP | AVCODES |
| 2 | NPL | Air Nepal International | | | ICAO1 |
| 3 | NPL | Neopul - Sociedade de Estudos e Construção, S.A. | | PT | VKM |
| 4 | NPLC | NADEAU, PHILIPPE LOGGING CONTRACTOR | | | SCAC3 |
| 5 | NPLG | NORTH POINT LOGISTICS INC | | | SCAC4 |
| 6 | NPLI | NATIONAL PIPELINE CO | | | SCAC3 |
| 7 | NPLK | NELSON, P L TRUCKING | | | SCAC4 |
| 8 | NPLP | NRG PETROLEUM LP | | | SCAC4 |
| 9 | NPLU | SAIGON NEWPORT ONE MEMBER LTD LIABILITY CORP | | VN | BIC |
| 10 | NPLU | NAURU PACIFIC LINE | | | SCAC3 |
| 11 | NPLW | NAVIG8 PTE LTD | | | SCAC4 |
| 12 | NPLX | North Pacific Lumber Co. | added 10/1979; 1/1980; eliminated 1/1981 | | NAKINA |
| 13 | NPLX | Nickel Plate-Lackawanna Dairy Line | 7/1932 | | NAKINA |
| 14 | NPLX | Nickel Plate-Lackawanna Dairy Line (New York, Chicago & St. Louis R.R. Co.) | 7/1930 | | NAKINA |
| 15 | NPLX | Nickel Plate-Lackawanna Dairy Line (Mid-West Despatch Car Co./Atlantic Seaboard Despatch) | 7/1923 | | NAKINA |
| 16 | NPLX | North Pacific Lumber Co. | 1/80; eliminated 1/81 | | NRHS |
| 17 | NPLX | *NICKEL PLATE-LACKAWANNA DAIRY LINE | | | PWRC |
| 18 | NPLX | *NORTH PACIFIC LUMBER CO. | | | PWRC |
