| 1 | JAS | Japan Air System Co., Ltd. | IATA: JD, Callsign: Air System, IATA Prefix: 234, Merged into Japan Airlines International, Inc w.e.f. 31 March 2004. Name changed from TOA Domestic Airlines | J | AVCODES |
| 2 | JAS | Kackson Air Services Ltd. | Callsign: Jackson, | CDN | AVCODES |
| 3 | JAS | Jet Aviation Flight Services, Inc | Callsign: Jet Setter, Name changed from Jet Aviation Business Jets. ICAO designator changed from BZF. ICAO callsign changed from Bizfleet. | USA | AVCODES |
| 4 | JAS | Japan Air System | Real: JAS, JD | J | TRAFFIC |
| 5 | JASB | JASKO | | | SCAC4 |
| 6 | JASC | JOONG ANG SHIPPING CO LTD | | | SCAC4 |
| 7 | JASDF | Japan Air Self-Defense Force | | J | TRAFFIC |
| 8 | JASF | JAS OCEAN SERVICES INC | | | SCAC4 |
| 9 | JASJ | JAS TRANSPORT INC | | | SCAC4 |
| 10 | JASLO | Zakład Miejskiej Komunikacji Samochodowej w Jaśle | City: Jasło | PL | TRAFFIC |
| 11 | JASO | J & A SONS INC | | | SCAC4 |
| 12 | JASP | JOHNSON AIRSPRAY INC | | | SCAC4 |
| 13 | JASQ | JAS CARRIERS INC | | | SCAC4 |
| 14 | JAST | JASA TRANSIT INC | | | SCAC4 |
| 15 | JAST | Przedsiębiorstwo Komunikacji Miejskiej w Jastrzębiu-Zdroju | | PL | TRAFFIC |
| 16 | JASU | JACKSON SHIPPING INC. | | | SCAC1 |
| 17 | JASV | JOHNSTON AIRCRAFT SERVICE INC | | | SCAC4 |
| 18 | JASW | JASON'S TRUCKING | | | SCAC4 |
| 19 | JASY | JETSTREAM AVIATION SERVICES LLC | | | SCAC4 |
