| 1 | FLX | Florida Express, Inc. | Callsign: Flexair, | USA | AVCODES |
| 2 | FLX | Flight Express, Inc. | Callsign: Flight Express, ICAO designator changed from EXR | USA | AVCODES |
| 3 | FLX | Flight Express | | | ICAO1 |
| 4 | FLX | Finkbine Lumber Co. | 8/1920 | | NAKINA |
| 5 | FLX | FINKBINE LUMBER CO. | | | PWRC |
| 6 | FLXA | FLEET TRANSIT INC | | | SCAC4 |
| 7 | FLXB | FULLER TRANSPORT LLC | | | SCAC4 |
| 8 | FLXC | FLEXI-VAN LEASING, INC. | | | PWRC |
| 9 | FLXC | FREIGHT LINKS EXPRESS | | | SCAC3 |
| 10 | FLXC | FLEXI-VAN LEASING INC | | | SCAC4 |
| 11 | FLXD | FLEXSTEEL INDUSTRIES INC | | | SCAC4 |
| 12 | FLXE | FREIGHT LINE EXPRESS TRUCKING | | | SCAC4 |
| 13 | FLXF | FLEXIBLE FLYER TRANSIT COMPANY | | | SCAC3 |
| 14 | FLXH | FLOUR EXPRESS INC | | | SCAC4 |
| 15 | FLXI | FELIX TRUCKING | | | SCAC3 |
| 16 | FLXI | FELIX TRUCKING COMPANY | | | SCAC4 |
| 17 | FLXI | The Flxible Co | | USA | TRAFFIC |
| 18 | FLXJ | FLEXTRONICS | | | SCAC4 |
| 19 | FLXM | FELIX COMPANY INC | | | SCAC3 |
| 20 | FLXP | FLATLINERS EXPRESS INC | | | SCAC4 |
| 21 | FLXQ | FELIXSTOWE SHIPPING | | | SCAC3 |
| 22 | FLXQ | FRONTIER LOGISTIX | | | SCAC4 |
| 23 | FLXR | FREEDOM LINE EXPRESS | | | SCAC3 |
| 24 | FLXR | FLUX, BLAIR E | | | SCAC4 |
| 25 | FLXS | FLEXSTEEL INDUSTRIES INC | | | SCAC3 |
| 26 | FLXT | FLEXIBLE TRANSPORTATION INC | | | SCAC3 |
| 27 | FLXT | FLEXIBLE TRANSPORTATION INC | | | SCAC4 |
| 28 | FLXU | FLEXI-VAN LEASING, INC. | | | PWRC |
| 29 | FLXU | Flexi-Van Leasing | | | RSRV |
| 30 | FLXU | GENSTAR CONTAINER CORPORATION | | | SCAC4 |
| 31 | FLXV | FLATLANDER TRANSPORT LTD | | | SCAC4 |
| 32 | FLXW | FLEXIBLE WAREHOUSING | | | SCAC3 |
| 33 | FLXY | FEC HIGHWAY SERVICES LLC | | | SCAC4 |
| 34 | FLXZ | FLEXI-VAN LEASING, INC. | | | PWRC |
| 35 | FLXZ | Flexi-Van Leasing | | | RSRV |
| 36 | FLXZ | FLEXI-VAN LEASING, INC. | | | SCAC3 |
