| 1 | TTU | TTT Air | Callsign: Valda, | CZ | AVCODES |
| 2 | TTU | Tantalus Air | Callsign: Tantalus, | CDN | AVCODES |
| 3 | TTUF | THOMPSON TRANSPORTATION | | | SCAC4 |
| 4 | TTUG | TOWN TRUCKING LLC | | | SCAC4 |
| 5 | TTUI | TAYLOR TRUCKING | | | PWRC |
| 6 | TTUI | THREE (3) TTT TRUCKING | | | SCAC4 |
| 7 | TTUK | TRANSTAR TRUCKING INC | | | SCAC4 |
| 8 | TTUL | TENDER TOUCH MOVING COMPANY INC | | | SCAC4 |
| 9 | TTUN | TTI TRUCKING | | | SCAC4 |
| 10 | TTUQ | TROPHY TRANSPORT | | | SCAC4 |
| 11 | TTUT | TNS TRUCKING LTD | | | SCAC4 |
| 12 | TTUU | TRANSTEC LTD | | RUS | BIC |
| 13 | TTUU | TRANSTEK LTD | | | SCAC4 |
| 14 | TTUX | Trailer Train Co. | added 7/1983; eliminated 1/1992 | | NAKINA |
| 15 | TTUX | TTX Co. | added 1/1992; 1/1994-7/2005 | | NAKINA |
| 16 | TTUX | Trailer Train Co./TTX Co. (single platform TOFC cars with single axle trucks and rigid hitch, capable of carrying one trailer 40' to 48' long and up to 102"" wide, with nose-mounted refrigeration unit between lift-on/lift-off facilities only) | added 7/1983; 7/1985-1/1994 | | NAKINA |
| 17 | TTUX | Trailer Train Co. | eliminated 1/92 | | NRHS |
| 18 | TTUX | TTX Co. | added 1/92; 1/94 | | NRHS |
| 19 | TTUX | TTX COMPANY {TRAILER TRAIN COMPANY} | | | PWRC |
| 20 | TTUX | Trailer Train (TTX Corporation) | | | RSRV |
| 21 | TTUX | TTX COMPANY | | | SCAC4 |
