| 1 | AJA | A J Services Limited | Callsign: Ayjay Services, | GB | AVCODES |
| 2 | AJA | Al Jaber Aviation | | UAE | AVCODES |
| 3 | AJA | Afghan Jet International Airlines | Callsign: Afghan Jet, Ceased operations on 15 June 2016. | AFG | AVCODES |
| 4 | AJA | A J Services | | | ICAO1 |
| 5 | AJAC | AJ & COMPANY | | | SCAC3 |
| 6 | AJAC | AJAXTEL INC | | | SCAC4 |
| 7 | AJAE | A J AIR EXPRESS | | | SCAC3 |
| 8 | AJAE | AUTOTRANSPORTES LA JARRITA SA DE CV | | | SCAC4 |
| 9 | AJAF | AJA FORWARDING COMPANY | | | SCAC3 |
| 10 | AJAG | AGUILAR, JOSE ANGEL | | | SCAC4 |
| 11 | AJAK | ARPIN VAN LINES INC (ARPIN OF JACKS | | | SCAC4 |
| 12 | AJAM | ALEMANY-MARTI J A INC, MAYAGUEZ PR | | | SCAC3 |
| 13 | AJAP | A J & ASSOCIATES LLC | | | SCAC4 |
| 14 | AJAQ | AJAX WAREHOUSE INC | | | SCAC3 |
| 15 | AJAX | Agramericas, Inc. | added 7/2007 | | NAKINA |
| 16 | AJAX | Ajax Transportation Co., Inc. | 7/1937-1/1943 | | NAKINA |
| 17 | AJAX | Ajax Tank Car Co. | 7/1930-7/1932 | | NAKINA |
| 18 | AJAX | Ajax Transportation Co., Inc. | Apr-38 | | NRHS |
| 19 | AJAX | *AJAX TRANSPORTATION CO. [AJAX TANK CAR CO.] | | | PWRC |
| 20 | AJAX | +AGRAMERICAS, INC. | | | PWRC |
| 21 | AJAX | AJAX TRANS CO, INC | | | SCAC3 |
