| 1 | STX | Aerocharter | Callsign: Sky Taxi, | CZ | AVCODES |
| 2 | STX | Stars Away Aviation | | ZA | AVCODES |
| 3 | STX | Stars Away Aviation | | | ICAO1 |
| 4 | STX | M. Steffen & Co., Inc. | 1/1943-4/1961; eliminated 7/1961 | | NAKINA |
| 5 | STX | M. Steffen & Co., Inc. | 1/52-4/61 | | NRHS |
| 6 | STX | M. STEFFEN & CO., INC. | | | PWRC |
| 7 | STXA | STEALTH TRANSPORT | | | SCAC4 |
| 8 | STXB | STARKS TRANSPORTATIONS LLC | | | SCAC4 |
| 9 | STXG | STAR TEX GASOLINE & OIL DIST | | | SCAC4 |
| 10 | STXI | STEELERS EXPRESS INC | | | SCAC4 |
| 11 | STXN | SUDDATH RELOCATION SYSTEMS OF TEXAS | | | SCAC4 |
| 12 | STXO | SCHIMIDT TRUCKING | | | SCAC4 |
| 13 | STXQ | STALEY GENERAL TRANSPORTATION, INC | | | SCAC1 |
| 14 | STXQ | STALEY GENERAL TRANSPORTATION INC | | | SCAC4 |
| 15 | STXS | STREAMLINE EXPRESS INC | | | SCAC4 |
| 16 | STXT | SOUTHERN TRUCKING OF TEXARKANA LLC | | | SCAC4 |
| 17 | STXU | STAXXON LLC | | USA | BIC |
| 18 | STXU | Staxxon | | | RSRV |
| 19 | STXX | South Texas Cotton Oil Co. | 7/1930 | | NAKINA |
| 20 | STXX | SOUTH TEXAS COTTON OIL CO. | | | PWRC |
| 21 | STXY | SERVICE TRUCKING COMPANY LLC | | | SCAC4 |
