| 1 | HOR | Horizon Air-Taxi Ltd. | Callsign: Horizon, | CH | AVCODES |
| 2 | HOR | Horizon Air-Taxi | | | ICAO1 |
| 3 | HORA | HOLMES, RUSS TRANSPORT INC | | | SCAC4 |
| 4 | HORC | HEIRLOOM ORIENTAL RUG CLEANING LTD | | | SCAC4 |
| 5 | HORI | HORN INTERNATIONAL FORWARDING INC | | | SCAC4 |
| 6 | HORI | Hokuriku Railroad | | J | TRAFFIC |
| 7 | HORK | HOTWORK-USA LLC | | | SCAC4 |
| 8 | HORN | HORNSBY EXPRESS INC | | | SCAC4 |
| 9 | HORNSBY | Hornsby Travel | City: Hornsby | GB | TRAFFIC |
| 10 | HORO | HO-RO TRUCKING CO | | | SCAC1 |
| 11 | HORO | HO-RO TRUCKING CO INC | | | SCAC4 |
| 12 | HORON | Horonai Railway | 1869 - | J | TRAFFIC |
| 13 | HORQ | HORNISH BROS | | | SCAC1 |
| 14 | HORQ | HORNISH BROS INC | | | SCAC4 |
| 15 | HORU | HORIZON PETROLEUM AND GAS GROUP LIM | | | SCAC4 |
| 16 | HORW | HORWITH TRUCKS INC | | | SCAC4 |
| 17 | HORX | Hodgeson Oil Refining Co. | 7/1935-1/1946 | | NAKINA |
| 18 | HORX | Hodgeson Oil Refining Co. | Apr-38 | | NRHS |
| 19 | HORX | HODGESON OIL REFINING CO. | | | PWRC |
