| 1 | GRR | Agroar - Trabalhos Aereos | | | ICAO1 |
| 2 | GRR | Georgetown R.R. Co. | 1/1975-7/2000; eliminated 10/2001; added 10/2003; eliminated 4/2004; added 7/2005; 7/2005; eliminated 1/2006 | | NAKINA |
| 3 | GRR | Georgetown R.R. Co. | 1/75-7/2000 | | NRHS |
| 4 | GRR | GEORGETOWN RAILROAD CO. | | | PWRC |
| 5 | GRR | Georgetown Railroad | | | RSRV |
| 6 | GRR | Georgetown Railroad Company | | USA | TRAFFIC |
| 7 | GRRA | GRAND RAPIDS TRANSFER AND STORAGE, | | | SCAC4 |
| 8 | GRRB | GRIMM, RICHARD R | | | SCAC4 |
| 9 | GRRD | GRUPO RAMSA DE MATAMOROS | | | SCAC4 |
| 10 | GRRF | GARCIA RUVALCALBA, FLORENCIO | | | SCAC4 |
| 11 | GRRG | GRUPO REFRIGERADOS DEL SUR | | | SCAC4 |
| 12 | GRRI | G A R R TRUCKLINES | | | SCAC4 |
| 13 | GRRJ | GUNVILLE TRUCKING | | | SCAC4 |
| 14 | GRRK | GRAY ROCK FARMS INC | | | SCAC4 |
| 15 | GRRM | GREENTREE TRANSPORTATION CO | | | SCAC1 |
| 16 | GRRM | GREENTREE TRANSPORTATION | | | SCAC4 |
| 17 | GRRO | GUERRERO GUERRERO, JOSE DANIEL | | | SCAC4 |
| 18 | GRRQ | GREATER TATER | | | SCAC4 |
| 19 | GRRT | Grand River Transit | | CDN | TRAFFIC |
| 20 | GRRU | GRANDEE PTE LTD | | | SCAC4 |
| 21 | GRRW | GARROW OIL MARKETING INC | | | SCAC4 |
| 22 | GRRX | Wampum Hardware | 1/1994-7/2005 (not listed) | | NAKINA |
| 23 | GRRX | Good Rich Refining Co., Ltd. | 1/1945-4/1947 | | NAKINA |
| 24 | GRRX | O.E. Linsin, Inc. | 7/1937 | | NAKINA |
| 25 | GRRX | The Golden Rule Refining Co. | 8/1920-7/1935 | | NAKINA |
| 26 | GRRX | Wampum Hardware | 1/94-7/2000 | | NRHS |
| 27 | GRRX | *GOOD RICH REFINING CO. [O.E. LINSIN, INC.; GOLDEN RULE REFINING CO.] | | | PWRC |
| 28 | GRRX | +WAMPUM HARDWARE COMPANY | | | PWRC |
| 29 | GRRX | Good Rich Refining (Wampum Hardware) | | | RSRV |
| 30 | GRRY | GREENBRIER RIVER RAILWAY | | | PWRC |
| 31 | GRRZ | GENEVA RAILROAD | | | PWRC |
