| 1 | HO | Antinea Airlines | ICAO: DJA, Callsign: Antinea, IATA Prefix: 394, Founded in June 1999. Merged into Khalifa Airways in 2001, and the company ceased to exist in 2003. Designator HO recalled by IATA | DZ | AVCODES |
| 2 | HO | Juneyao Airlines Co. Ltd. | ICAO: DKH, Callsign: Air Juneyao, IATA Prefix: 018, | PRC | AVCODES |
| 3 | HO | Austrian Air Services | Subsidary of Austrian Airlines | A | AVCODES |
| 4 | HO | Hoogovens (Corus) | | NL | TRAFFIC |
| 5 | HOA | Baleares Link Express S.L. t/a Hola Airlines | IATA: H5, Callsign: Hola, Ceased operations on 15 February 2010. Formed by ex management from Air Europa Express | E | AVCODES |
| 6 | HOA | Hola Airlines | IATA: H5 | | ICAO1 |
| 7 | HOAG | HOAGLANDS TRANSPORT SERIVCE | | | SCAC4 |
| 8 | HOAK | HOMESTEAD MORGANS | | | SCAC4 |
| 9 | HOAL | HOT SHOT FREIGHT | | | SCAC4 |
| 10 | HOAM | HOLM TRUCKING INC | | | SCAC4 |
| 11 | HOAP | HOWARD & SONS TRUCKING INC | | | SCAC4 |
| 12 | HOAQ | HOFFMAN | | | SCAC4 |
| 13 | HOAS | HOUSE, JASON D TRUCKING LLC | | | SCAC4 |
| 14 | HOB | HL Aircraft LLC | Callsign: Hobby Jet, | USA | AVCODES |
| 15 | HOB | HENDERSON OVERTON BRANCH | | | SCAC4 |
| 16 | HOB | Hoboken Transportation | | USA | TRAFFIC |
| 17 | HOBB | HOBBS TRUCKING CO | | | SCAC1 |
| 18 | HOBBY | Hobbytrain | | X | TRAFFIC |
| 19 | HOBE | HORIZON ENERGY TRANSPORT LLC | | | SCAC4 |
| 20 | HOBI | HODGEN BUTANE INC | | | SCAC4 |
| 21 | HOBL | HOBBS, LARRY FARM EQUIPMENT INC | | | SCAC4 |
| 22 | HOBR | HOBBY TRUCKING | | | SCAC4 |
| 23 | HOBU | BURG SERVICE BV | | NL | BIC |
| 24 | HOBU | HOLVRIEKA BV | | | SCAC4 |
| 25 | HOBY | HONEOYE AUTO PARTS | | | SCAC4 |
| 26 | HOC | Homac Aviation Services AG | Callsign: Homac, | D | AVCODES |
| 27 | HOC | CHOCTAW TRANSPORT INC | | | SCAC4 |
| 28 | HOCA | HANCOR OF CANADA INC | | | SCAC4 |
| 29 | HOCB | HALCOMB OIL CO | | | SCAC4 |
| 30 | HOCC | HOME OIL CO INC | | | SCAC4 |
| 31 | HOCE | HOC-EXPRESS, INC | | | SCAC1 |
| 32 | HOCE | HOC EXPRESS INC | | | SCAC4 |
| 33 | HOCF | HERSHBERGER OIL COMPANY LLC | | | SCAC4 |
| 34 | HOCG | HOC TRUCKING INC | | | SCAC4 |
| 35 | HOCI | HENRY OIL CO INC | | | SCAC4 |
| 36 | HOCK | HOCKER OIL COMPANY | | | SCAC4 |
| 37 | HOCM | HARBERT OIL COMPANY INC | | | SCAC4 |
| 38 | HOCO | HOKENBROUGH, M D TRUCKING INC | | | SCAC4 |
| 39 | HOCQ | H CARGO LINES | | | SCAC4 |
| 40 | HOCR | HANSEN OIL COMPANY | | | SCAC4 |
| 41 | HOCU | HOEGH CONTAINER LINES | | | PWRC |
| 42 | HOCU | Hoegh Container Lines | | | RSRV |
| 43 | HOCX | Hunt Oil Co. | 1/1943-1/1946 | | NAKINA |
| 44 | HOCX | Head-On Collision Line | added 4/1957; 10/1957-1/1980; eliminated 1/1991 | | NAKINA |
| 45 | HOCX | Head-On Collision Line | added 4/57; 10/57-1/80; eliminated 1/91 | | NRHS |
| 46 | HOCX | *HUNT OIL CO. | | | PWRC |
| 47 | HOCX | *HEAD-ON COLLISION LINE | | | PWRC |
| 48 | HOCX | Head-On Collision Line | | | RSRV |
| 49 | HOD | Alhodhod Airline | Callsign: Hodhod, | YAR | AVCODES |
| 50 | HODA | HOLIDAY TOURS INC | | | SCAC4 |
| 51 | HODG | HODGE, PETER TRANSPORT LIMITED | | | SCAC4 |
| 52 | HODM | Hód-Mez? | City: Hódmezõvásárhely | H | TRAFFIC |
| 53 | HODO | HOWARD DEDICATED OPERATIONS INC | | | SCAC4 |
| 54 | HODQ | HODGES, ED F INC | | | SCAC4 |
| 55 | HODT | HBX INC | | | SCAC4 |
| 56 | HOE | G.Hölzig | | DE | VKM |
| 57 | HOEC | HOLIDAY EXPRESS CORPORATION | | | SCAC4 |
| 58 | HOEE | HOLMES FREIGHT LINES INC | | | SCAC4 |
| 59 | HOEG | HOEGH AUTOLINERS AS | | | SCAC4 |
| 60 | HOEH | HOEGH, DANIEL | | | SCAC4 |
| 61 | HOEI | HOLMES OIL CO INC | | | SCAC4 |
| 62 | HOEL | HOTWHEELS TRUCKING | | | SCAC4 |
| 63 | HOEP | HOEPPNER, DOUGLAS M A | | | SCAC4 |
| 64 | HOES | HOESE TRUCKING | | | SCAC4 |
| 65 | HOEU | HOECHST AKTIENGESELLSCHAFT | | | PWRC |
| 66 | HOEU | Hoechst Aktiengesellschaft | | | RSRV |
| 67 | HOEU | HOECHST AKTIENGESELLSCHAFT | | | SCAC4 |
| 68 | HOFF | Manfred Hoffmann Baumaschinen Industrieservice | | DE | VKM |
| 69 | HOFFM | Hoffmann Erdbau Straenbau Tiefbau GmbH & Co. KG | | DE | VKM |
| 70 | HOFI | HOFFMAN TRANSIT COMPANY INC | | | SCAC4 |
| 71 | HOFL | HOLMES FREIGHT LINES, INC | | | SCAC1 |
| 72 | HOFL | HOLMES FREIGHT LINES, INC | | | SCAC4 |
| 73 | HOFM | HOFFMANN TRUCKING | | | SCAC4 |
| 74 | HOFQ | HOFF BROS. CARTAGE, INC | | | SCAC1 |
| 75 | HOFQ | HERCULES OILFIELD CONSTRUCTION INC | | | SCAC4 |
| 76 | HOFU | HOFER TANKTRANSPORTE AG | | CH | BIC |
| 77 | HOFU | HOFER TANKTRANSPORTE AG | | | SCAC4 |
| 78 | HOG | Arkansas Traveler Airline | Callsign: Hog-Air, | USA | AVCODES |
| 79 | HOG | Mahogany Air Charters | IATA: KT, Callsign: Hogan Air, Suspended operations in 2014. | Z | AVCODES |
| 80 | HOG | Heart of Georgia R.R., Inc. | 7/2000-7/2005 | | NAKINA |
| 81 | HOG | Heart of Georgia R.R., Inc. | Jul-00 | | NRHS |
| 82 | HOG | HEART OF GEORGIA RAILROAD | | | PWRC |
| 83 | HOG | Heart of Georgia Railroad | | | RSRV |
| 84 | HOG | HEART OF GEORGIA RAILROAD INC | | | SCAC4 |
| 85 | HOG | Heart of Georgia | | USA | TRAFFIC |
| 86 | HOGD | HOGAN DEDICATED SERVICES LLC | | | SCAC4 |
| 87 | HOGE | HOGEMANN TRANSPORT LTD | | | SCAC4 |
| 88 | HOGH | HOSIEN, GHASSAN | | | SCAC4 |
| 89 | HOGL | HOAGLAND'S TRANSPORT SERVICE, INC. | | | SCAC1 |
| 90 | HOGL | HOAGLANDS TRANSPORT SERVICE, INC | | | SCAC4 |
| 91 | HOGT | HOGLAND TRANSFER CO | | | SCAC1 |
| 92 | HOGW | HOG WILD TRANSPORT | | | SCAC4 |
| 93 | HOGX | Clougherty Packing Co. | added 1/1990; 1/1994; eliminated 4/1997 | | NAKINA |
| 94 | HOGX | Harlis Oil & Gas Co. | 7/1923 | | NAKINA |
| 95 | HOGX | Clougherty Packing Co. | added 1/90; 1/94; eliminated 4/97 | | NRHS |
| 96 | HOGX | *HARLIS OIL & GAS CO. | | | PWRC |
| 97 | HOGX | *CLOUGHERTY PACKING | | | PWRC |
| 98 | HOGX | *UNION PACIFIC RAILROAD | | | PWRC |
| 99 | HOGX | Harlis Oil & Gas (Union Pacific Railroad) | | | RSRV |
| 100 | HOHF | HOSS, H F | | | SCAC4 |