| 1 | KTR | HT Helikoptertransport AB | Callsign: Copter Trans, Name changed to AB Flygtjanst F.J. Viklund | S | AVCODES |
| 2 | KTR | AB Flygtjanst F.J. Viklund | Callsign: Copter Trans, Name changed from HT Helikoptertransport AB | S | AVCODES |
| 3 | KTR | LLC SkyAviaTrans | AOC revoked by SAAU on 15 November 2019. | UA | AVCODES |
| 4 | KTR | HT Helikoptertransport | | | ICAO1 |
| 5 | KTR | Kendallville Terminal Ry. Co. | 7/2005 | | NAKINA |
| 6 | KTR | KENDALLVILLE TERMINAL RAILWAY | | | PWRC |
| 7 | KTR | Kendallville Terminal Railway | | | RSRV |
| 8 | KTR | KENDALLVILLE TERMINAL RAILWAY CO | | | SCAC4 |
| 9 | KTR | Kitakinki Tango Railway | | J | TRAFFIC |
| 10 | KTRA | K-TRAN CORP | | | SCAC3 |
| 11 | KTRA | KUNSMAN TRANSPORT LTD | | | SCAC4 |
| 12 | KTRB | K OCEAN TRANSPORT LLC | | | SCAC4 |
| 13 | KTRC | KERINS TRANSPORTATION CO INC | | | SCAC3 |
| 14 | KTRD | KINGSERV TRADING SUPPLYING LTD | | | SCAC3 |
| 15 | KTRH | KLIMCO TRANSPORT | | | SCAC4 |
| 16 | KTRI | KAR-A-VAN TRANSFER INC | | | SCAC3 |
| 17 | KTRK | KING TRUCKING CO, INC | | | SCAC3 |
| 18 | KTRL | KELLER TRANSFER LINE, INC | | | SCAC3 |
| 19 | KTRL | KELLER TRANSFER LINE INC | | | SCAC4 |
| 20 | KTRM | KREUZIGER TRUCKING | | | SCAC4 |
| 21 | KTRO | KOMNICK TRUCKING | | | SCAC3 |
| 22 | KTRO | KC TRANSPORT | | | SCAC4 |
| 23 | KTRP | KENIAS TRANSPORT LLC | | | SCAC4 |
| 24 | KTRQ | KRENEK TRACTOR REPAIR | | | SCAC3 |
| 25 | KTRQ | KONE TRANSPORT | | | SCAC4 |
| 26 | KTRR | KINGDOM TRUCKING | | | SCAC4 |
| 27 | KTRS | KING TRAVEL SERVICE | | | SCAC3 |
| 28 | KTRT | KLB TRUCKING | | | SCAC4 |
| 29 | KTRW | KEE TRANS INC | | | SCAC4 |
| 30 | KTRY | KTI RECYCLING OF NEW ENGLAND INC | | | SCAC4 |
