| 1001 | HCSU | HACON CONTAINERS B.V | | NL | BIC |
| 1002 | HCSU | HACON CONTAINERS BV | | | SCAC4 |
| 1003 | HCSX | Helm Chesapeake Limited Partnership | added 10/2001; 7/2005 | | NAKINA |
| 1004 | HCSX | HELM CHESAPEAKE, LP | | | PWRC |
| 1005 | HCSX | Helm Chesapeake | | | RSRV |
| 1006 | HCSX | HELM CHESAPEAKE LIMITED PARTNERSHIP | | | SCAC4 |
| 1007 | HCSX | Helm Chesapeake Limited Partnership | | USA | TRAFFIC |
| 1008 | HCSY | HS CARMEN SHIPPING COMPANY LTD | | | SCAC4 |
| 1009 | HCT | Cathelicopters S.L. | Callsign: Rotorcat, | E | AVCODES |
| 1010 | HCTA | HELMS, CHRIS TRANSPORTATION LLC | | | SCAC4 |
| 1011 | HCTB | HAT CREEK TRUCK BROKERAGE CORP | | | SCAC4 |
| 1012 | HCTC | HAMPTON, CHRIS TRUCKING | | | SCAC4 |
| 1013 | HCTD | HIGH COUNTRY TRANSPORTATION INC | | | SCAC4 |
| 1014 | HCTG | HACKL, J K TRANSPORTATION SERVICES | | | SCAC4 |
| 1015 | HCTI | HITCHCOCK TRUCKING INC | | | SCAC4 |
| 1016 | HCTM | HARRIS CAMDEN TERMINAL EQUIPMENT CO | | | SCAC4 |
| 1017 | HCTOR | Hector Rail AB | 2004 - | S | svenska-lok.se |
| 1018 | HCTOR | Hector Rail AB | | SE | VKM |
| 1019 | HCTR | HILL COUNTRY TRUCKING INC | | | SCAC4 |
| 1020 | HCTT | HIGH COUNTRY TRANSPORT LTD | | | SCAC4 |
| 1021 | HCTU | HAMILTON CONTAINER TERMINAL | | CDN | BIC |
| 1022 | HCTU | COMMISSARIAT DE LA MARINE | | | SCAC4 |
| 1023 | HCTV | HELICOPTER TRANSPORT SERVICES INC | | | SCAC4 |
| 1024 | HCTX | Martin Marietta Corp. | added 4/1990; 1/1994; eliminated 7/1996; 7/2000 (not listed) | | NAKINA |
| 1025 | HCTX | Hallett Construction Co. | added 4/1971; 1/1975-1/1980; eliminated 4/1990 | | NAKINA |
| 1026 | HCTX | Hallett Construction Co. | added 4/71; 1/75-1/80; eliminated 4/90 | | NRHS |
| 1027 | HCTX | Martin Marietta Corp. | added 4/90; 1/94; eliminated 7/96; 7/2000 | | NRHS |
| 1028 | HCTX | *HALLETT CONSTRUCTION CO. | | | PWRC |
| 1029 | HCTX | *(MMAX) MARTIN MARIETTA CORPORATION | | | PWRC |
| 1030 | HCTX | Hallett Construction (Martin Marietta Corporation) | | | RSRV |
| 1031 | HCV | Halcyonair Cabo Verde Airways | IATA: 7Z, Callsign: Creole, Ceased operations. | CV | AVCODES |
| 1032 | HCV | Hamburg City Vision | City: Hamburg, Sightseeing | D | TRAFFIC |
| 1033 | HCVU | HONG CHUN ELECTRIC & MACHINERY CO LTD | | RC | BIC |
| 1034 | HCVU | HONG CHUN ELECTRIC & MACHINERY CO L | | | SCAC4 |
| 1035 | HCW | HC Airways JSC | Callsign: Hermis Capital, | LT | AVCODES |
| 1036 | HCW | Star1 Airlines | IATA: V9, Suspended operations and filed for bankruptcy. | LT | AVCODES |
| 1037 | HCWC | HOLY COW CANOE CO | | | SCAC4 |
| 1038 | HCX | Aerocom Aviation Oy t/a Helsinki Citycopter | Callsign: City Copter, | FIN | AVCODES |
| 1039 | HCX | Hallet and Carey Ltd. | added 1/1953; eliminated 10/1953 | | NAKINA |
| 1040 | HCX | Merchants Despatch Transportation Corp. | 1/1941-1/1950 | | NAKINA |
| 1041 | HCX | Hardwood Chemical Co. (General American Transportation Corp.) | 7/1935 | | NAKINA |
| 1042 | HCX | Hallet and Carey Ltd. | added 1/53; eliminated 10/53 | | NRHS |
| 1043 | HCX | *MERCHANTS DESPATCH TRANSPORTATION CORP. | | | PWRC |
| 1044 | HCX | *HALLET & CAREY LTD. | | | PWRC |
| 1045 | HCXC | HOC TRANSPORT COMPANY | | | SCAC4 |
| 1046 | HCXN | HCS TRANSPORTATION | | | SCAC4 |
| 1047 | HCY | Helios Airways Ltd | IATA: ZU, Callsign: Helios, Established on 23 September 1998. Commenced operations on 15 May 2000. Name changed to Ajet w.e.f. 14 March 2006. Helios Airways Ltd | CY | AVCODES |
| 1048 | HCY | Helios Airways Ltd | IATA: ZU, Callsign: Helios, IATA designator changed to ZU | CY | AVCODES |
| 1049 | HCY | Helios Airways | IATA: ZU | | ICAO1 |
| 1050 | HCY | Hill City Ry. Co. | 7/1923 | | NAKINA |
| 1051 | HCY | HILL CITY RWY. CO. | | | PWRC |
| 1052 | HCYR | Horry County Ry. Co. | added 7/1985; eliminated 1/1988 | | NAKINA |
| 1053 | HCYR | Horry County Ry. Co. | eliminated 1/88 | | NRHS |
| 1054 | HCYR | HORRY COUNTY RAILWAY CO. | | | PWRC |
| 1055 | HCYR | Horry County Railway | | | RSRV |
| 1056 | HCZ | HERCULES COMPANY | | | PWRC |
| 1057 | HCZU | HARDING CONTAINERS INTERNATIONAL INC. | | USA | BIC |
| 1058 | HCZU | Harding Containers International | | | RSRV |
| 1059 | HCZU | HARDING CONTAINERS INTERNATIONAL IN | | | SCAC4 |
| 1060 | HD | Hokkaido International Airlines Co., Ltd. | ICAO: ADO, Callsign: Air Do, Name changed to Air Do Co., Ltd. | J | AVCODES |
| 1061 | HD | New York Helicopters Corp. | ICAO: NYH, Callsign: New York, Designator HD recalled by IATA | USA | AVCODES |
| 1062 | HD | Aeroservicios S.r.l. | | HN | AVCODES |
| 1063 | HD | Air Holland | ICAO: AHD, Callsign: Air Holland, Founded in 1984. Commenced operations in 1985. Suspended all operations in December 1991. ICAO callsign changed to Orange | NL | AVCODES |
| 1064 | HD | Air Holland | ICAO: AHD, Callsign: Orange, Founded in 1984. Commenced operations in 1985. Suspended all operations in December 1991. ICAO callsign changed from Air Holland | NL | AVCODES |
| 1065 | HD | Air Do Co., Ltd. | ICAO: ADO, Callsign: Air Do, Name changed from Hokkaido International Airlines Co., Ltd. | J | AVCODES |
| 1066 | HD | Holger Dietz | | DE | VKM |
| 1067 | HDA | Hong Kong Dragon Airlines Limited t/a Dragonair | IATA: KA, Callsign: Dragonair, IATA Prefix: 043, ICAO callsign changed to Dragon | HK | AVCODES |
| 1068 | HDA | Hong Kong Dragon Airlines Limited t/a Dragonair | IATA: KA, Callsign: Dragon, IATA Prefix: 043, ICAO callsign changed from Dragonair. Name changed to Hong Kong Dragon Airlines Limited t/a Cathay Dragon. | HK | AVCODES |
| 1069 | HDA | Dragonair (DAL) | Callsign: Dragonair, Name chanaged to Hong Kong Dragon Airlines - Dragonair | HK | AVCODES |
| 1070 | HDA | Hong Kong Dragon Airlines Limited t/a Cathay Dragon | IATA: KA, Callsign: Dragon, IATA Prefix: 043, Founded on 24 May 1985. Commenced operations in July 1985. Ceased operations on 21 October 2020. ICAO callsign changed from Dragonair . Name changed from Hong Kong Dragon Airlines Limited t/a Dragonair. | HK | AVCODES |
| 1071 | HDA | Dragonair, Hong Kong Dragon Airlines | IATA: KA | | ICAO1 |
| 1072 | HDA | Dragonair | | HK | TRAFFIC |
| 1073 | HDAE | HEIFETZ, DAVID | | | SCAC4 |
| 1074 | HDAI | HERNANDEZ DIAZ, ANTONIO MARTIN G | | | SCAC4 |
| 1075 | HDAV | H A D D TRUCKING LLC | | | SCAC4 |
| 1076 | HDBA | HALF DIAMOND EXPRESS LTD | | | SCAC4 |
| 1077 | HDBB | HILL DE BAJA CALIFORNIA | | | SCAC4 |
| 1078 | HDBE | HILDEBRAND, JIM | | | SCAC4 |
| 1079 | HDBG | HYDER, B & A TRUCKING CO INC | | | SCAC4 |
| 1080 | HDBQ | HYDE DRIFT BOATS INCORPORATED | | | SCAC4 |
| 1081 | HDBS | HOUND DOG BUS | | | SCAC4 |
| 1082 | HDBX | Blery Oil Co. | 8/1920 | | NAKINA |
| 1083 | HDBX | BLERY OIL CO. | | | PWRC |
| 1084 | HDC | Helicopteros de Cataluna, S.A. | Callsign: Helicataluna, | E | AVCODES |
| 1085 | HDC | Helcopteros De Cataluna | | | ICAO1 |
| 1086 | HDCM | HURTADO CRUZ, MIGUEL | | | SCAC4 |
| 1087 | HDCN | HUDD TRANSPORTATION | | | SCAC4 |
| 1088 | HDCO | H DANTAS COMERCIO NAVEGACAO E INDUS | | | SCAC4 |
| 1089 | HDCR | HILLSDALE COUNTY RAILWAY | | | PWRC |
| 1090 | HDCR | HAPPY D CORPORATION | | | SCAC4 |
| 1091 | HDCW | HOLMAN DISTRIBUTION CENTER OF WASHINGTON, INC | | | SCAC1 |
| 1092 | HDCW | HOLMAN TRANSPORTATION LLC | | | SCAC4 |
| 1093 | HDCX | The Hull Corp. | 1/1994 (not listed) | | NAKINA |
| 1094 | HDCX | The Hull Corp. | Jan-94 | | NRHS |
| 1095 | HDCX | THE HULL CORPORATION | | | PWRC |
| 1096 | HDDA | HERNDON, D A INC | | | SCAC4 |
| 1097 | HDDC | HENRY, DAN DISTRIBUTING CO | | | SCAC4 |
| 1098 | HDDD | HADDAD APPAREL GROUP LTD | | | SCAC4 |
| 1099 | HDDE | HENRIE, DANIEL DENIS | | | SCAC4 |
| 1100 | HDDH | HADDON HOUSE FOOD PRODUCTS INC | | | SCAC4 |
