| 5101 | GRSX | +GUNDERSON RAIL SERVICES | | | PWRC |
| 5102 | GRSX | Gunderson Rail Services | | | RSRV |
| 5103 | GRSX | GUNDERSON RAIL SERVICES | | | SCAC4 |
| 5104 | GRSZ | GREATER SOUTHWEST COMPANY | | | PWRC |
| 5105 | GRT | Gabon-Air-Transport | | G | AVCODES |
| 5106 | GRT | Gabon-Air-Transport | | | ICAO1 |
| 5107 | GRT | Grampian Regional Transport | | GB | TRAFFIC |
| 5108 | GRTA | GARRED TRANSPORT INC | | | SCAC4 |
| 5109 | GRTC | Greater Richmond Transit Company | City: Richmond (VA) | USA | TRAFFIC |
| 5110 | GRTE | GROUND AIR TRANSFER OF CLEVELAND, INC | | | SCAC1 |
| 5111 | GRTK | GRINE TRUCKING INC | | | SCAC4 |
| 5112 | GRTL | GREAT LAKES TRANSPORTATION LLC | | | SCAC4 |
| 5113 | GRTN | GREAT NORTHERN | | | SCAC4 |
| 5114 | GRTO | GARCIA TRANSPORTES | | | SCAC4 |
| 5115 | GRTP | GRT TRANSFER SA DE CV | | | SCAC4 |
| 5116 | GRTQ | GAREM TRANSPORTES | | | SCAC4 |
| 5117 | GRTR | GREAT RIVER RAILROAD | | | PWRC |
| 5118 | GRTR | GRT TRANSPORTATION LLC | | | SCAC4 |
| 5119 | GRTT | GROENDYKE TRANSPORT, INC | | | SCAC4 |
| 5120 | GRTU | HULDA MARITIME INTERNATIONAL CONTAINER | | HK | BIC |
| 5121 | GRTV | GARRISON, R. E., TRUCKING INC | | | SCAC1 |
| 5122 | GRTV | GARRISON, R E TRUCKING INC | | | SCAC4 |
| 5123 | GRTX | Savage-Tolk Energy Services | added 4/2001; eliminated 7/2005; 7/2005 (not listed) | | NAKINA |
| 5124 | GRTX | Wheelabrator Coal Services Co. | added 4/1994; 7/2000; eliminated 4/2001 | | NAKINA |
| 5125 | GRTX | Wheelabrator Coal Services Co. | added 4/94; 7/2000; eliminated 4/2001 | | NRHS |
| 5126 | GRTX | Savage-Tolk Energy Services | added 4/2001 | | NRHS |
| 5127 | GRTX | SAVAGE-TOLK ENERGY SERVICES (WCSX) [WHEELABRATOR COAL SERVICES] | | | PWRC |
| 5128 | GRTX | Savage-Tolk Energy Services | | | RSRV |
| 5129 | GRTX | SAVAGE-TOLK ENERGY SERVICES | | | SCAC4 |
| 5130 | GRU | GRAFTON & UPTON RAILROAD CO. | | | PWRC |
| 5131 | GRUD | Miejski Zaklad Komunikacji w Grudziadzu | Real: MZKG, City: Grudziadz | PL | TRAFFIC |
| 5132 | GRUE | GRUELLE, D T COMPANY | | | SCAC4 |
| 5133 | GRUF | GRUPO FIGUEROA TRANSPORTA S A DE C | | | SCAC4 |
| 5134 | GRUI | GRUPO INNOVADOR DE COAHUILA S A | | | SCAC4 |
| 5135 | GRUL | GRANITE PLUS INC | | | SCAC4 |
| 5136 | GRUM | Grumman | | USA | TRAFFIC |
| 5137 | GRUR | GRUPO LOGICO LLC | | | SCAC4 |
| 5138 | GRUS | GREEN LIGHT COURIER | | | SCAC4 |
| 5139 | GRUT | GRUBES TRUCKING INC | | | SCAC4 |
| 5140 | GRUU | GRUBER GMBH & CO.KG | | D | BIC |
| 5141 | GRUU | GRUBER GMBH & CO KG | | | SCAC4 |
| 5142 | GRV | Vernicos Aviation, S.A. | Callsign: Night Rider, Name changed to Epsilon Aviation | GR | AVCODES |
| 5143 | GRV | Grosvenor Aviation Servcies Ltd. | Callsign: Grosvenor, | GB | AVCODES |
| 5144 | GRV | Epsilon Aviation, S.A. | Callsign: Night Rider, Name changed from Vernicos Aviation, S.A. | GR | AVCODES |
| 5145 | GRV | Vernicos Aviation | | | ICAO1 |
| 5146 | GRVA | GRAY VAN EXPRESS, INC | | | SCAC1 |
| 5147 | GRVB | GRAVES, BENNIE TRUCKING INC | | | SCAC4 |
| 5148 | GRVD | GRAVAL CORPORATION | | | SCAC4 |
| 5149 | GRVE | GLEN RAVEN TRANSPORTATION INC | | | SCAC4 |
| 5150 | GRVF | GROVES, F. W | | | SCAC1 |
| 5151 | GRVH | GREEN REVOLUTION INC, THE | | | SCAC4 |
| 5152 | GRVI | GRAEBEL VAN LINES INC | | | SCAC4 |
| 5153 | GRVJ | GENERAL RV CENTER INC | | | SCAC4 |
| 5154 | GRVL | GROVER, LYLE INC | | | SCAC4 |
| 5155 | GRVP | GUERRERO AVALOS, FELIPE DE | | | SCAC4 |
| 5156 | GRVS | GRAVES OIL COMPANY INC | | | SCAC4 |
| 5157 | GRVT | GARVEY TRANSPORT, INC | | | SCAC1 |
| 5158 | GRVU | GREVILLE CONTAINER CORP | | | SCAC4 |
| 5159 | GRW | Gary Railway Co. | added 4/2009 | | NAKINA |
| 5160 | GRW | GREAT WESTERN TOURS | | | PWRC |
| 5161 | GRW | GARY RAILWAY COMPANY | | | SCAC4 |
| 5162 | GRWA | GREENWAY | | | SCAC4 |
| 5163 | GRWB | GREWAL BROTHER INC | | | SCAC4 |
| 5164 | GRWC | GROWERS CHEMICAL CORP | | | SCAC4 |
| 5165 | GRWE | GRANDVIEW ENTERPRISES INC | | | SCAC4 |
| 5166 | GRWH | GRATTON WAREHOUSE COMPANY | | | SCAC4 |
| 5167 | GRWI | GILL ROADWAYS INC | | | SCAC4 |
| 5168 | GRWK | GROWMARK INC | | | SCAC4 |
| 5169 | GRWR | Great Walton R.R. Co. | 1/1994-7/2005 | | NAKINA |
| 5170 | GRWR | Great Walton R.R. Co. | 1/94-7/2000 | | NRHS |
| 5171 | GRWR | GREAT WALTON RAILROAD CO. | | | PWRC |
| 5172 | GRWR | Great Walton Railroad | | | RSRV |
| 5173 | GRWR | GREAT WALTON RAILROAD CO, THE | | | SCAC4 |
| 5174 | GRWT | GRIMWOOD TRUCKING | | | SCAC4 |
| 5175 | GRWU | GRW ENGINEERING (PTY) LTD | | ZA | BIC |
| 5176 | GRWY | GREENWAY TRANSPORTATION SERVICES IN | | | SCAC4 |
| 5177 | GRX | Aircompany Grodno | Callsign: Grodno, | BY | AVCODES |
| 5178 | GRX | Aircompany Grodno | | | ICAO1 |
| 5179 | GRX | Grandfield Oil & Refining Co. | 7/1923 | | NAKINA |
| 5180 | GRX | GRANDFIELD OIL & REFINING CO. | | | PWRC |
| 5181 | GRXC | GREER TRANSPORT LLC | | | SCAC4 |
| 5182 | GRXO | GIROUX OIL CO INC | | | SCAC4 |
| 5183 | GRXQ | G & R AUTO TRANSPORT INC | | | SCAC4 |
| 5184 | GRXS | GRAND RIVER ENTERPRISES SIX NATIONS | | | SCAC4 |
| 5185 | GRXT | GUERRA TRANSPORT | | | SCAC4 |
| 5186 | GRXU | GOODRICH MARITIME PRIVATE LIMITED | | IND | BIC |
| 5187 | GRXU | GOODRICH MARITIME PRIVATE LIMITED | | | SCAC4 |
| 5188 | GRY | New York State Police | Callsign: Gray Rider, | USA | AVCODES |
| 5189 | GRY | New York State Police | | | ICAO1 |
| 5190 | GRYC | GRAYPORT TRANSFER & STORAGE | | | SCAC4 |
| 5191 | GRYE | GRAY, E G TRANSPORTATION LTD | | | SCAC4 |
| 5192 | GRYF | Przewozy Autobusowe Gryf | | PL | TRAFFIC |
| 5193 | GRYFK | Przewozy Autobusowe Gryf sp. z o.o. | | PL | TRAFFIC |
| 5194 | GRYGLAS | Auto-Szkola Gryglas | | PL | TRAFFIC |
| 5195 | GRYJ | GRAY, JACK TRANSPORT INC | | | SCAC4 |
| 5196 | GRYM | GEORGIA RECYCLERS LLC | | | SCAC4 |
| 5197 | GRYO | GRAY TRANSPORTAITON INC | | | SCAC4 |
| 5198 | GRYQ | GRAY LINE CARGO | | | SCAC4 |
| 5199 | GRYR | Grenada Railway | | | RSRV |
| 5200 | GRYR | GRANADA RAILWAY LLC | | | SCAC4 |
