| 1 | GCT | GC Aviation, Inc | Callsign: Gulf Coast, Merged in Volato, Inc. (TMB) | USA | AVCODES |
| 2 | GCTB | G & C TRANSPORTATION INC | | | SCAC4 |
| 3 | GCTC | G & C TRUCKING INC | | | SCAC4 |
| 4 | GCTD | GARICK CORPORATION, THE | | | SCAC4 |
| 5 | GCTG | GARDEN CITY GROWERS | | | SCAC4 |
| 6 | GCTH | GULF COAST TANK LINES LLC | | | SCAC4 |
| 7 | GCTL | GCT | | | SCAC4 |
| 8 | GCTM | GULF COAST CHAPTER-NRHS | | | PWRC |
| 9 | GCTN | GREAT CENTRAL TRANSPORT INC | | | SCAC4 |
| 10 | GCTO | GARCIA TRANSPORT COMPANY, Eastern Oregon Fast Freight, INC | | | SCAC1 |
| 11 | GCTS | GULFCOAST TRANSPORTATION SYSTEMS IN | | | SCAC4 |
| 12 | GCTU | GULF CONTAINER LINES | | | PWRC |
| 13 | GCTU | Gulf Container Lines | | | RSRV |
| 14 | GCTU | GULF CONTAINER LINES | | | SCAC4 |
| 15 | GCTW | GREEN CITY TRUCKING LTD | | | SCAC4 |
| 16 | GCTX | General Chemical Corp. | added 7/1987; 1/1994-7/2005 | | NAKINA |
| 17 | GCTX | General Chemical Corp. | added 7/87; 1/94-7/2000 | | NRHS |
| 18 | GCTX | GENERAL CHEMICAL CORPORATION | | | PWRC |
| 19 | GCTX | General Chemical Corporation | | | RSRV |
| 20 | GCTX | GENERAL CHEMICAL CORPORATION | | | SCAC4 |
