| 1 | HTL | Jet Linx Aviation | Callsign: Heartland, | USA | AVCODES |
| 2 | HTL | My Fair Jet GmbH | Callsign: Hotline, | A | AVCODES |
| 3 | HTL | Jet Link Aviation | | | ICAO1 |
| 4 | HTLC | HOMEFOLK TRANSPORTATION, LLC | | | SCAC4 |
| 5 | HTLF | HILLMANS TRANSFER LTD | | | SCAC4 |
| 6 | HTLI | HANNA TRUCK LINE INC | | | SCAC4 |
| 7 | HTLJ | HTL INC | | | SCAC4 |
| 8 | HTLN | HOLTON TRUCK LINE | | | SCAC4 |
| 9 | HTLO | HARTT LOGISTICS | | | SCAC4 |
| 10 | HTLQ | HTL | | | SCAC4 |
| 11 | HTLS | HORIZON TANK LINES INC | | | SCAC4 |
| 12 | HTLU | SHENZHEN HUITAI STEEL MANUFACTURE CO., LTD. | | PRC | BIC |
| 13 | HTLX | Haymer Transport Leasing Co. | added 1/1970; 4/1970; eliminated 7/1971 | | NAKINA |
| 14 | HTLX | Haymer Transport Leasing Co. | added 1/70; 4/70 | | NRHS |
| 15 | HTLX | HAYMER TRANSPORT LEASING CO. | | | PWRC |
| 16 | HTLY | HARTLEY TRUCKING COMPANY, INC | | | SCAC1 |
