| 4501 | GPLX | Getz Live Poultry Car Corp. | 7/1935 | | NAKINA |
| 4502 | GPLX | Getz Poultry and Egg Corp. | Apr-38 | | NRHS |
| 4503 | GPLX | General American Transportation Corp. | added 10/92; 1/94; eliminated 1/98 | | NRHS |
| 4504 | GPLX | General American Marks Co. | added 1/98; 7/2000 | | NRHS |
| 4505 | GPLX | *GETX POULTRY & EGG CORP. | | | PWRC |
| 4506 | GPLX | +GENERAL AMERICAN MARKS CO. [GENERAL AMERICAN TRANSPORTATION CORP.] | | | PWRC |
| 4507 | GPLX | General American Marks (GATX Corporation) | | | RSRV |
| 4508 | GPLZ | GOOD PASTURE LEAD | | | PWRC |
| 4509 | GPM | Grup Air-Med, S.A. | Callsign: Grupomed, | E | AVCODES |
| 4510 | GPM | Grup Air-Med | | | ICAO1 |
| 4511 | GPMB | Grand Port Maritime de Bordeaux | | FR | VKM |
| 4512 | GPMC | GUS PECH MFG CO INC | | | SCAC4 |
| 4513 | GPMG | G P M TRUCKING CORPORATION INC | | | SCAC4 |
| 4514 | GPMI | GRUPO MEXICO | | | SCAC4 |
| 4515 | GPML | GIRARD PALLET MANAGEMENT LLC | | | SCAC4 |
| 4516 | GPMR | GRAEBEL/PITTSBURGH MOVERS INC | | | SCAC4 |
| 4517 | GPMS | GRUPO MIALVA S A DE C V | | | SCAC4 |
| 4518 | GPMT | G P M TRANSPORT INC | | | SCAC4 |
| 4519 | GPMT | GP Papenburg Maschinentechnik GmbH | | DE | VKM |
| 4520 | GPMU | {LLC "GAZPROMTRANS"};ZIPCODE=117420 | | RUS | BIC |
| 4521 | GPMX | Georgia-Pacific LLC | added 4/2007 | | NAKINA |
| 4522 | GPMX | Georgia-Pacific Corp. | eliminated 4/2007 | | NAKINA |
| 4523 | GPMX | Georgia-Pacific Corp., Mid-Continent Wood Products Manufacturing Division | added 10/1986; added 7/1987; added 10/1989; 1/1994-7/2005 | | NAKINA |
| 4524 | GPMX | Gas Properties Management Co. | added 7/1962; 7/1965-4/1970; eliminated 4/1973 | | NAKINA |
| 4525 | GPMX | Union Oil Co. of California, Glacier Division | 1/1946-1/1950 | | NAKINA |
| 4526 | GPMX | Glacier Production Co. | 7/1937-1/1945 | | NAKINA |
| 4527 | GPMX | Glacier Production Co. | Apr-38 | | NRHS |
| 4528 | GPMX | Gas Properties Management Co. | 7/65-4/70; eliminated 4/73 | | NRHS |
| 4529 | GPMX | Georgia-Pacific Corp., Mid-Continent Wood Products Manufacturing Division | added 10/86; added 7/87; added 10/89; 1/94-7/2000 | | NRHS |
| 4530 | GPMX | *UNION OIL CO. OF CALIFORNIA, GLACIER DIV. | | | PWRC |
| 4531 | GPMX | *GAS PROPERTIES MANAGEMENT CO. | | | PWRC |
| 4532 | GPMX | +GEORGIA PACIFIC LLC - MID-CONTINENT WOOD PRODS MFG DIV | | | PWRC |
| 4533 | GPMX | Georgia-Pacific Corporation (Mid Continent Wood Products Manufacturing Division) | | | RSRV |
| 4534 | GPMX | GEORGIA PACIFIC LLC | | | SCAC4 |
| 4535 | GPO | Northern Aviation Ltd | Callsign: Goosepool, | GB | AVCODES |
| 4536 | GPO | GEORGIA PACIFIC (OREGON) | | | PWRC |
| 4537 | GPOA | GALLEGOS PADILLA, OSCAR ALBERTO | | | SCAC4 |
| 4538 | GPOI | GODWIN PUMPS OF AMERICA INC | | | SCAC4 |
| 4539 | GPON | GOLD POINT TRANSPORTATION INC | | | SCAC4 |
| 4540 | GPPC | G P PLASTICS CORPORATION | | | SCAC4 |
| 4541 | GPPX | Georgia Pacific Chemicals LLC | added 4/2007 | | NAKINA |
| 4542 | GPPX | Georgia-Pacific Corp. | 7/2000-7/2005; eliminated 4/2007 | | NAKINA |
| 4543 | GPPX | Georgia-Pacific Corp., Chemical Division | added 10/1992; 1/1994 | | NAKINA |
| 4544 | GPPX | Georgia-Pacific Corp., Portland Division | added 4/1978; 1/1980; eliminated 10/1992 | | NAKINA |
| 4545 | GPPX | Georgia-Pacific Corp., Portland Division | added 4/78; 1/80; eliminated 10/92 | | NRHS |
| 4546 | GPPX | Georgia-Pacific Corp., Chemical Division | added 10/92; 1/94 | | NRHS |
| 4547 | GPPX | Georgia-Pacific Corp. | Jul-00 | | NRHS |
| 4548 | GPPX | GEORGIA-PACIFIC CHEMICALS, LLC | | | PWRC |
| 4549 | GPPX | Georgia-Pacific Corporation (Portland Division) | | | RSRV |
| 4550 | GPPX | GEORGIA PACIFIC CHEMICALS LLC | | | SCAC4 |
| 4551 | GPR | GPM Aeroservicio, S.A. de C.V. | Callsign: Gpm Aeroservicio, | MEX | AVCODES |
| 4552 | GPR | GPM Aeroservicio | | | ICAO1 |
| 4553 | GPR | GREAT PLAINS RAILROAD | | | PWRC |
| 4554 | GPR | GP Rail Cargo | | RO | TRAFFIC |
| 4555 | GPRB | GETHSEMANE PROJECT | | | SCAC4 |
| 4556 | GPRN | GLOBAL PROPANE | | | SCAC4 |
| 4557 | GPRS | GULF PUERTO RICO LINES | | | PWRC |
| 4558 | GPRU | GUINESS, ARTHUR SON AND CO LTD | | | SCAC4 |
| 4559 | GPRX | Quartermaster Corps, War Department, U.S.A. | 7/1937-1/1941 | | NAKINA |
| 4560 | GPRX | United States of America (War Department, U.S.A.) | 7/1935 | | NAKINA |
| 4561 | GPRX | United States of America | 8/1920-7/1932 | | NAKINA |
| 4562 | GPRX | Quartermaster Corps, War Department, U.S.A. | Apr-38 | | NRHS |
| 4563 | GPRX | UNITED STATES OF AMERICA WAR DEPARTMENT (WW II AND EARLIER) | | | PWRC |
| 4564 | GPS | ABS Avia | Callsign: Alatau, | KZ | AVCODES |
| 4565 | GPSE | GOODMAN TANK LINES INC | | | SCAC4 |
| 4566 | GPSF | G & P TRUCKING COMPANY INC (G & P S | | | SCAC4 |
| 4567 | GPSG | GLOBAL PARCEL SYSTEM | | | SCAC4 |
| 4568 | GPSI | GLOBAL PLASTICS SERVICES INTERNATIO | | | SCAC4 |
| 4569 | GPSJ | G P SERVICE LLC | | | SCAC4 |
| 4570 | GPSK | GPS TRIAXLE INC | | | SCAC4 |
| 4571 | GPSR | GLOBAL POSTAL SERVICES | | | SCAC4 |
| 4572 | GPSS | GPS EXPRESS INC | | | SCAC4 |
| 4573 | GPST | GRIPP, STEVE INC | | | SCAC4 |
| 4574 | GPSV | GIRTON PROPANE SERVICE INC | | | SCAC4 |
| 4575 | GPSX | Georgia-Pacific LLC | added 4/2007 | | NAKINA |
| 4576 | GPSX | Georgia-Pacific Corp. | eliminated 4/2007 | | NAKINA |
| 4577 | GPSX | Georgia-Pacific Corp. | 7/2000 | | NAKINA |
| 4578 | GPSX | Georgia-Pacific Corp., Eastern Wood Products Manufacturing Division | eliminated 4/2004; 7/2005 (not listed); added 4/2006 | | NAKINA |
| 4579 | GPSX | Georgia-Pacific Corp., Eastern Wood Products Manufacturing Division | added 1/1984; 1/1994 | | NAKINA |
| 4580 | GPSX | Georgia-Pacific Corp., Southern Division | added 7/1972; 1/1975-1/1980; eliminated 1/1984 | | NAKINA |
| 4581 | GPSX | Georgia-Pacific Corp., Southern Division | 1/75-1/80 | | NRHS |
| 4582 | GPSX | Georgia-Pacific Corp., Eastern Wood Products Manufacturing Division | Jan-94 | | NRHS |
| 4583 | GPSX | Georgia-Pacific Corp. | Jul-00 | | NRHS |
| 4584 | GPSX | *GETTYSBURG PASSENGER SERVICE | | | PWRC |
| 4585 | GPSX | +GEORGIA-PACIFIC LLC | | | PWRC |
| 4586 | GPSX | Georgia-Pacific Corporation (Eastern Wood Products Manufacturing Division) | | | RSRV |
| 4587 | GPSX | GEORGIA-PACIFIC CORP.,EAST.WOOD PRO | | | SCAC4 |
| 4588 | GPSX | Georgia-Pacific Corp. | | USA | TRAFFIC |
| 4589 | GPSY | GPS TRANSPORT LLC | | | SCAC4 |
| 4590 | GPT | Promodal Transportes Aereos Ltda | Callsign: Promodal, Established in 2003. Operations ceased in 2004. | BR | AVCODES |
| 4591 | GPTB | GREAT PLAINS TRANSPORTATION INC | | | SCAC4 |
| 4592 | GPTBEL | Gorodskoy Passazhirsoy Transport Belgorod | | RUS | TRAFFIC |
| 4593 | GPTC | G&P TRUCKING COMPANY, INC. | | | SCAC1 |
| 4594 | GPTC | G & P TRUCKING COMPANY INC | | | SCAC4 |
| 4595 | GPTD | G & P TRUCKING | | | SCAC4 |
| 4596 | GPTE | GENERAL GAS CARRIER CORPORATION III | | | SCAC4 |
| 4597 | GPTH | GREAT PLAINS TRANSPORT INC | | | SCAC4 |
| 4598 | GPTI | G & P TRUCKING COMPANY INC (INTERMO | | | SCAC4 |
| 4599 | GPTJ | GP THOMPSON ENTERPRISES | | | SCAC4 |
| 4600 | GPTK | GINNETTI PETROLEUM TRANSPORTERS LLC | | | SCAC4 |
