| 1 | HTR | Holstenair Lubeck, Luftverkehrsservice GmbH & Co. Betriebs-KG | Callsign: Holsten, | D | AVCODES |
| 2 | HTR | Holstenair Lubeck | | | ICAO1 |
| 3 | HTRA | H & E AIR CARTAGE | | | SCAC4 |
| 4 | HTRD | HIGHLAND-TROY READY MIX MATERIAL DIVISION, INC | | | SCAC1 |
| 5 | HTRF | HANSON TRANSFER, INC | | | SCAC1 |
| 6 | HTRF | HERMES TRANSPORT | | | SCAC4 |
| 7 | HTRI | HULL TRUCKING OF MASON CITY INC | | | SCAC4 |
| 8 | HTRL | HUNTERLINE | | | SCAC4 |
| 9 | HTRM | HUNTER OIL CO INC | | | SCAC4 |
| 10 | HTRN | HUNTER TRANSPORTATION COMPANY INCOR | | | SCAC4 |
| 11 | HTRS | HTRS Süd GmbH | Neuoffingen (HTRS = Husa Transportation Railway Sevices) | D | privat-bahn.de |
| 12 | HTRS | HALTER TRANSPORTATION SERVICES INC | | | SCAC4 |
| 13 | HTRSN | HTRNS Nederland bv | | NL | VKM |
| 14 | HTRT | HERNANDEZ TRUCKING | | | SCAC4 |
| 15 | HTRU | HARDY TANK LTD | | RUS | BIC |
| 16 | HTRW | HOLLAND TRUCKING | | | SCAC4 |
| 17 | HTRX | Houston Terminal Refining Co. | 7/1923-7/1930 | | NAKINA |
| 18 | HTRX | HOUSTON TERMINAL REFINING CO. | | | PWRC |
