| 5901 | GTMO | GRAEBEL/TENNESSE | | | SCAC4 |
| 5902 | GTMP | GRAN TURISMO MOTORSPORTS INC | | | SCAC4 |
| 5903 | GTMQ | GLOBAL TRANSPORTATION MANAGEMENT LL | | | SCAC4 |
| 5904 | GTMR | GENCO TRANSPORTATION MANAGEMENT LLC | | | SCAC4 |
| 5905 | GTMS | GARRETT MOVING & STORAGE | | | SCAC4 |
| 5906 | GTMU | GTM MANUFACTURING LLC | | USA | BIC |
| 5907 | GTMU | GTM Manufacturing | | | RSRV |
| 5908 | GTMU | GTM INDUSTRIES LLC | | | SCAC4 |
| 5909 | GTMV | GTM SERVICES INC | | | SCAC4 |
| 5910 | GTMW | GORDON TRUCKING INC (GP MIDWEST DED | | | SCAC4 |
| 5911 | GTMY | GROUPE TAG MARINE INC | | | SCAC4 |
| 5912 | GTNB | GREEN TREE TRANSPORT | | | SCAC4 |
| 5913 | GTNE | G & T | | | SCAC4 |
| 5914 | GTNH | GREAT NORTHERN TRANSPORTATION SERVI | | | SCAC4 |
| 5915 | GTNJ | GERRYS TRAILER SHUTTLE | | | SCAC4 |
| 5916 | GTNK | GUNTREN TRUCKING | | | SCAC4 |
| 5917 | GTNN | GREAT NORTHERN TRANSPORTATION CO | | | SCAC4 |
| 5918 | GTNP | GOLD TRANSPORTATION CORP | | | SCAC4 |
| 5919 | GTNT | GRUPO TRANSPORTISTA CASTILLO | | | SCAC4 |
| 5920 | GTOA | GREAT TASTE OF TEXAS, THE | | | SCAC4 |
| 5921 | GTOD | GLOBAL TRANSLOADING LLC | | | SCAC4 |
| 5922 | GTOF | GATES RUBBER COMPANY, THE | | | SCAC4 |
| 5923 | GTOG | GTO GLOBAL TRANSPORT INC | | | SCAC4 |
| 5924 | GTOH | GREENWOODS TOWING | | | SCAC4 |
| 5925 | GTOI | G T OIL CO INC | | | SCAC4 |
| 5926 | GTOK | GTO TRUCKING | | | SCAC4 |
| 5927 | GTOM | GRENIER, TOMY | | | SCAC4 |
| 5928 | GTOS | G T O TRANSPORT | | | SCAC4 |
| 5929 | GTOT | GTO TWO THOUSAND (2000) INC | | | SCAC4 |
| 5930 | GTOU | GLOBAL TRANSPORTE OCEANICO SA | | | SCAC4 |
| 5931 | GTOV | GTL TRANSPORTATION INC (OUTBOUND) | | | SCAC4 |
| 5932 | GTOW | GUARDADO TOWING | | | SCAC4 |
| 5933 | GTP | Aerotaxi Grupo Tampico, S.A. de C.V. | Callsign: Grupotampico, | MEX | AVCODES |
| 5934 | GTP | Aerotaxi Grupo Tampico | | | ICAO1 |
| 5935 | GTP | Grand Trunk Pacific Ry. (Canadian National Railways) | 7/1935-7/1954 | | NAKINA |
| 5936 | GTP | Grand Trunk Pacific Ry. | 4/38-1/52 | | NRHS |
| 5937 | GTP | CANADIAN NATIONAL RWYS. [GRAND TRUNK PACIFIC RAILWAY] (EXPIRED) | | | PWRC |
| 5938 | GTP | Grand Trunk Pacific Railway | | | RSRV |
| 5939 | GTPD | G & T SPECIALISTS INC | | | SCAC4 |
| 5940 | GTPH | GRACE TRANSPORTATION INC | | | SCAC4 |
| 5941 | GTPI | GRANT TRANSPORT INC | | | SCAC4 |
| 5942 | GTPL | GO TRANSPORT LTD | | | SCAC4 |
| 5943 | GTPLO | Gradski Transport Plovdiv | City: Plovdiv | BG | TRAFFIC |
| 5944 | GTPO | GTP LOGISTICS | | | SCAC4 |
| 5945 | GTPP | GLOBAL TANKER POOL PTE LTD | | | SCAC4 |
| 5946 | GTPR | Grand Trunk Pacific Railway | | | RSRV |
| 5947 | GTPS | GRAY TRANSPORT SERVICE LLC | | | SCAC4 |
| 5948 | GTPT | GARRETT TRANSPORTATION SERVICES INC | | | SCAC4 |
| 5949 | GTPU | GTS SPA | | I | BIC |
| 5950 | GTPU | GTS SPA | | | SCAC4 |
| 5951 | GTPV | GLOBAL TRANSPORTATION SYSTEMS INC | | | SCAC4 |
| 5952 | GTPZ | TIT SERVICES | | | PWRC |
| 5953 | GTPZ | TIT Services | | | RSRV |
| 5954 | GTPZ | TIP SERVICES | | | SCAC4 |
| 5955 | GTQ | CANADIAN NATIONAL | | | PWRC |
| 5956 | GTR | Galistair Trading Limited | IATA: GH, Callsign: Galister, | M | AVCODES |
| 5957 | GTR | Gestar | | | ICAO1 |
| 5958 | GTR | Great River R.R. Rosedale-Bolivar County Port Commission | added 1/1984; 1/1994-7/2005 | | NAKINA |
| 5959 | GTR | Great River R.R. Rosedale-Bolivar County Port Commission | 1/94-7/2000 | | NRHS |
| 5960 | GTR | GREAT RIVER RAILROAD d/b/a ROSEDALE-BOLIVAR COUNTY PORT COMMISSION | | | PWRC |
| 5961 | GTR | Great River Railroad (Rosedale-Bolivar County Port Commission) | | | RSRV |
| 5962 | GTR | Goldschmidt Thermit Railservice (Österreich) GmbH | | AT | VKM |
| 5963 | GTRA | Golden Triangle R.R. | added 7/1982; 1/1994-7/2005 | | NAKINA |
| 5964 | GTRA | Golden Triangle R.R. | added 7/82; 1/94-7/2000 | | NRHS |
| 5965 | GTRA | GOLDEN TRIANGLE RAILROAD | | | PWRC |
| 5966 | GTRA | Golden Triangle Railroad | | | RSRV |
| 5967 | GTRA | GOLDEN TRIANGLE RAILROAD | | | SCAC4 |
| 5968 | GTRA | Golden Triangle R.R. | | USA | TRAFFIC |
| 5969 | GTRE | GRANT TRUCKING | | | SCAC4 |
| 5970 | GTRI | GRANTIER OIL CO INC | | | SCAC4 |
| 5971 | GTRJ | GRANTS TRANSPORT LIMITED | | | SCAC4 |
| 5972 | GTRK | G & T TRUCKING | | | SCAC4 |
| 5973 | GTRM | | ~Sorin Oprisan | GB | TRAFFIC |
| 5974 | GTRO | GREENSVILLE TRANSPORT COMPANY | | | SCAC4 |
| 5975 | GTRP | GUARDIAN TRANSPORTATION CORPORATION | | | SCAC4 |
| 5976 | GTRR | GTR TRANSPORT | | | SCAC4 |
| 5977 | GTRS | GLOBETROTTER TRANSPORT SERVICES | | | SCAC4 |
| 5978 | GTRT | GTRV-USA INC | | | SCAC4 |
| 5979 | GTRU | GENTENAAR TRANSPORT BV | | NL | BIC |
| 5980 | GTRW | GATOR PLANT CO | | | SCAC4 |
| 5981 | GTRX | The Goodyear Tire & Rubber Co. | 8/1920-7/1930 | | NAKINA |
| 5982 | GTRX | GOODYEAR TIRE & RUBBER CO. | | | PWRC |
| 5983 | GTRY | GENTRY TRUCKING | | | SCAC4 |
| 5984 | GTS | GATS Guinea, S.A. | Callsign: GATS Air, Name changed to GTS Bishkek Ltd. | GQ | AVCODES |
| 5985 | GTS | GATS Bishkek Ltd. | Callsign: GATS Air, Name changed from GATS Guinea, S.A. | KS | AVCODES |
| 5986 | GTS | Groupe Transair S.A. | IATA: R2, Callsign: Transgroup, | SN | AVCODES |
| 5987 | GTS | GTS - General Transport Service S.p.A | | I | TRAFFIC |
| 5988 | GTS | Gesellschaft für Gleistechnik Süd GmbH | | DE | VKM |
| 5989 | GTSA | GABRIELS TRANSPORTATION SERVICES LL | | | SCAC4 |
| 5990 | GTSB | GTS EXPRESS INC | | | SCAC4 |
| 5991 | GTSC | GREEN TRANSFER & STORAGE CO | | | SCAC4 |
| 5992 | GTSCH | GTS Rail Sagl | | CH | VKM |
| 5993 | GTSE | GENTECH SCIENTIFIC INC | | | SCAC4 |
| 5994 | GTSF | GENTILE TRANSPORTATION SERVICES INC | | | SCAC4 |
| 5995 | GTSI | GTS LOGISTICS | | | SCAC4 |
| 5996 | GTSJ | GSTC TRANSPORTATION SERVICES | | | SCAC4 |
| 5997 | GTSM | GRAHAM TRANSFER & STORAGE | | | SCAC4 |
| 5998 | GTSN | GITTS SPRING COMPANY | | | SCAC4 |
| 5999 | GTSO | GREAST SOUTHWEST EXPRESS CO | | | SCAC1 |
| 6000 | GTSO | GREAT SOUTHWEST EXPRESS CO INC | | | SCAC4 |
