| 4501 | HTTX | TTX COMPANY | PWRC | ||
| 4502 | HTTX | Trailer Train (TTX Corporation) | RSRV | ||
| 4503 | HTTX | TTX COMPANY | SCAC4 | ||
| 4504 | HTVN | HETCO VAN LINES INC | SCAC4 | ||
| 4505 | HTW | Hoosac Tunnel & Wilmington | 1/1994-7/2000 | NAKINA | |
| 4506 | HTW | Hoosac Tunnel & Wilmington | 1/94-7/2000 | NRHS | |
| 4507 | HTW | *HOOSAC TUNNEL AND WILMINGTON RAILROAD CO. | PWRC | ||
| 4508 | HTW | Hoosac Tunnel and Wilmington | RSRV | ||
| 4509 | HTWA | HODGE TRANSPORTATION & WAREHOUSING | SCAC4 | ||
| 4510 | HTWC | HALAL TOWING INC | SCAC4 | ||
| 4511 | HTWD | HOOSIER TRADEWINDS INC | SCAC4 | ||
| 4512 | HTWF | H2O FARMS | SCAC4 | ||
| 4513 | HTWG | HARTWIG, C TRANSPORT | SCAC4 | ||
| 4514 | HTWH | HAMILTON, E H TRUCKING & | SCAC4 | ||
| 4515 | HTWI | HARTWIG AIRCRAFT FUEL CELL REPAIR I | SCAC4 | ||
| 4516 | HTWJ | HTW LOGISTICS | SCAC4 | ||
| 4517 | HTWK | HAULMARK TRUCKING INC | SCAC4 | ||
| 4518 | HTWM | HATCHER, WILLIAM RAY TRUCKING CO | SCAC4 | ||
| 4519 | HTWQ | HAMNER TOWING INC | SCAC4 | ||
| 4520 | HTWT | HOT WATER TRUCKING LLC | SCAC4 | ||
| 4521 | HTWV | H TWO (2) | SCAC4 | ||
| 4522 | HTWY | HUTTER, WALLY OIL CO | SCAC4 | ||
| 4523 | HTX | Houston Tank Car Co. | 1/1952-10/1957; eliminated 4/1960 | NAKINA | |
| 4524 | HTX | The Hewitt Transportation Co. (The Hewitt Soap Co., Inc.) | 7/1937-4/1938 | NAKINA | |
| 4525 | HTX | The Hewitt Soap Co., Inc. | 7/1935 | NAKINA | |
| 4526 | HTX | The Hewitt Soap Co., Inc. | Apr-38 | NRHS | |
| 4527 | HTX | Houston Tank Car Co. | 1/52-10/57 | NRHS | |
| 4528 | HTX | HEWETT SOAP CO., INC. (HEWITT TRANSPORTATION CO.) | PWRC | ||
| 4529 | HTXC | HEAT TRANSFER LLC | SCAC4 | ||
| 4530 | HTXG | HIRTE TRANSFER & STORAGE | SCAC4 | ||
| 4531 | HTXI | HOPE TRANSPORT INC | SCAC4 | ||
| 4532 | HTXL | HIALEAH TRANSPORT LLC | SCAC4 | ||
| 4533 | HTXN | HEARNE TRANSPORTATION | SCAC4 | ||
| 4534 | HTXO | HAT TRANSPORT LLC | SCAC4 | ||
| 4535 | HTXT | HOLBORN TRANSPORT | SCAC4 | ||
| 4536 | HTYI | HARTLEY TRANSPORTATION INC | SCAC4 | ||
| 4537 | HTZI | HEITZ TRUCKING, INC | SCAC1 | ||
| 4538 | HTZI | HEITZ TRUCKING INC | SCAC4 | ||
| 4539 | HTZL | HETZELS OVERLAND TRANSPORT INC | SCAC4 | ||
| 4540 | HTZS | HOTZ ENVIRONMENTAL SERVICES INC | SCAC4 | ||
| 4541 | HU | HUPAC SpA | IT | VKM | |
| 4542 | HUAC | HUDSON ARMORED CAR & | SCAC4 | ||
| 4543 | HUAF | HUA FENG (USA) LOGISTICS INC | SCAC4 | ||
| 4544 | HUAF | Hungarian Air Force | Real: HUF | H | TRAFFIC |
| 4545 | HUAI | HUNDER, MYLES | SCAC4 | ||
| 4546 | HUAL | HUB AIRLINES INC | SCAC4 | ||
| 4547 | HUAN | HUB CITY ATLANTA TERMINALS INC | SCAC4 | ||
| 4548 | HUAU | HOEGH/UGLAND AUTOLINERS (HUAL) | SCAC1 | ||
| 4549 | HUAU | HOEGH/UGLAND AUTO LINERS, A/S | SCAC4 | ||
| 4550 | HUAV | HUNTER, AVERIL | SCAC4 | ||
| 4551 | HUAX | Huasteca Petroleum Co. | 7/1930-4/1938 | NAKINA | |
| 4552 | HUAX | Huasteca Petroleum Co. | Apr-38 | NRHS | |
| 4553 | HUAX | HUASTECA PETROLEUM CO. | PWRC | ||
| 4554 | HUB | Hub Airlines | ICAO1 | ||
| 4555 | HUB | HUDSON BUS LINES | SCAC4 | ||
| 4556 | HUBA | Hudson Bay | 1/1975-1/1980 | NAKINA | |
| 4557 | HUBA | Hudson Bay | 1/75-1/80 | NRHS | |
| 4558 | HUBA | BURLINGTON NORTHERN & SANTA FE RWY (BNSF) [HUDSON BAY CO. RR] | PWRC | ||
| 4559 | HUBA | Hudson Bay (BNSF Railway) | RSRV | ||
| 4560 | HUBB | HUB COMPUTER SOLUTIONS | SCAC4 | ||
| 4561 | HUBD | HUB DISPLAYWORKS INC | SCAC4 | ||
| 4562 | HUBERT | J. Hubert GmbH | D | TRAFFIC | |
| 4563 | HUBF | HUB FREIGHT USA INC | SCAC4 | ||
| 4564 | HUBG | HUDSON, BILLIE G | SCAC4 | ||
| 4565 | HUBM | HUBBARD, BOB HORSE TRANSPORTATION I | SCAC4 | ||
| 4566 | HUBO | HUB CITY TERMINALS INC | SCAC4 | ||
| 4567 | HUBP | HUB INC | SCAC4 | ||
| 4568 | HUBS | HUBBARDS TRANSPORTATION COMPANY | SCAC4 | ||
| 4569 | HUBX | Hubbard Creamery Co. (North Western Refrigerator Line Co.) | 7/1935 | NAKINA | |
| 4570 | HUBZ | HUBINGER COMPANY | PWRC | ||
| 4571 | HUBZ | HUB GROUP INC | SCAC4 | ||
| 4572 | HUC | Aerloineas de Techuacan | ICAO1 | ||
| 4573 | HUCA | HUTCHISON CARGO TERMINAL INC | SCAC4 | ||
| 4574 | HUCE | HUTCHENS TRUCKING COMPANY INC | SCAC4 | ||
| 4575 | HUCL | HUB CITY OF LOUISIANA TERMINALS INC | SCAC4 | ||
| 4576 | HUCT | HUTCH TRANSPORTATION | SCAC4 | ||
| 4577 | HUCX | Huron Portland Cement Co. | 7/1935-4/1961 | NAKINA | |
| 4578 | HUCX | Huron Portland Cement Co. | 4/38-4/61 | NRHS | |
| 4579 | HUCX | HURON PORTLAND CEMENT CO. | PWRC | ||
| 4580 | HUCZ | HURON CHEMICAL | PWRC | ||
| 4581 | HUD | Horizons Unlimited | ICAO1 | ||
| 4582 | HUDB | HUDSONS BAY COMPANY | SCAC4 | ||
| 4583 | HUDC | HOUSTON DISTRIBUTING COMPANY INC | SCAC4 | ||
| 4584 | HUDCB | GB | TRAFFIC | ||
| 4585 | HUDCT | Huddersfield Corporation Transport | GB | TRAFFIC | |
| 4586 | HUDG | HOUSTON, DOUG L | SCAC4 | ||
| 4587 | HUDK | HUNTLAND TRUCKING | SCAC4 | ||
| 4588 | HUDL | HUSKER DISTRIBUTION INC | SCAC4 | ||
| 4589 | HUDM | HUDSON, GAY, MOVING AND STORAGE COM | SCAC4 | ||
| 4590 | HUDMAN | Hudson & Manhattan | City: New York | USA | TRAFFIC |
| 4591 | HUDN | HUDSON TRUCKING | SCAC4 | ||
| 4592 | HUDR | HUDDLESTON, TROY TRUCKING LLC | SCAC4 | ||
| 4593 | HUDS | HUDSON TRANSPORTATION CO INC | SCAC4 | ||
| 4594 | HUDT | HUDINI TRANSPORTATION LTD | SCAC4 | ||
| 4595 | HUDT | Hudson Transit | US- | TRAFFIC | |
| 4596 | HUDX | Hudson Technologies, Inc. | 7/2000-7/2005 (not listed) | NAKINA | |
| 4597 | HUDX | Hudson Technologies, Inc. | Jul-00 | NRHS | |
| 4598 | HUDX | HUDSON TECHNOLOGIES INC | PWRC | ||
| 4599 | HUDX | Hudson Technologies | RSRV | ||
| 4600 | HUEL | HUENEMAN LOGISTICS LC | SCAC4 |