| 1 | TU | Tunisair | ICAO: TAR, Callsign: Tunair, IATA Prefix: 199, | TN | AVCODES |
| 2 | TUA | Turkmenistan Airlines | IATA: T5, Callsign: Turkmenistan, IATA Prefix: 542, Designator T5 reinstated by IATA. ICAO designator changed from AKH | TM | AVCODES |
| 3 | TUA | Turkmenhovayollary | | | ICAO1 |
| 4 | TUA | Turkmenistan Airlines | | TM | TRAFFIC |
| 5 | TUAA | TALERO USED AUTO PARTS | | | SCAC4 |
| 6 | TUAE | TURN A ROUND EXPRESS LLC | | | SCAC4 |
| 7 | TUAG | TRANSPORTES UNIDOS ARECHIGA S A DE | | | SCAC4 |
| 8 | TUAG | MARTI AG Tunnelbau | | CH | TRAFFIC |
| 9 | TUAH | TRANSPORT DAVE MICHAUD | | | SCAC4 |
| 10 | TUB | TUI Airlines Belgium S.A/N.V. | IATA: TB, Callsign: Beauty, Name changed to N.V. Jetair t/a Jetairfly.com | B | AVCODES |
| 11 | TUB | N.V. Jetair | IATA: TB, Callsign: Beauty, ICAO code changed to JAF w.e.f. 31 October 2006. Name changed from TUI Airlines Belgium | B | AVCODES |
| 12 | TUB | True Aviation Limited | IATA: 7B, Callsign: True Aviation, IATA Prefix: 557, | BD | AVCODES |
| 13 | TUB | Transports urbains briochins | City: Saint Brieuc | F | TRAFFIC |
| 14 | TUBC | TRU-BLUE TRUCKING LLC | | | SCAC4 |
| 15 | TUBE | TUBE PRO INC | | | SCAC4 |
| 16 | TUBG | TURBO LOGISTICS INC (OHL) | | | SCAC4 |
| 17 | TUBL | THOMAS FUELS LUBRICANTS AND CHEMICA | | | SCAC4 |
| 18 | TUBP | TURBO DEDICATED INC (OHL) | | | SCAC4 |
| 19 | TUBS | THRU TUBING SOLUTIONS | | | SCAC4 |
| 20 | TUBT | TURNER BROS. TRUCKING, INC | | | SCAC1 |
| 21 | TUC | Turismo Aereo de Chile Ltda. | Callsign: Turichile, | RCH | AVCODES |
| 22 | TUC | Turismo Aereo de Chile | | | ICAO1 |
| 23 | TUCB | TRUDEAU DISTRIBUTING COMPANY | | | SCAC4 |
| 24 | TUCD | TRUE COLOURS PRODUCTS | | | SCAC4 |
| 25 | TUCH | TOUCH TRANSPORTATION, INC | | | SCAC1 |
| 26 | TUCJ | TSUNAMI GLASSWORKS INC | | | SCAC4 |
| 27 | TUCK | TUCKER TRANSPORTATION LLC | | | SCAC4 |
| 28 | TUCL | TUCKER, L E & SON INC | | | SCAC4 |
| 29 | TUCM | TRUCKS MART TRANSPORT LLC | | | SCAC4 |
| 30 | TUCS | TUCSON MOVING SYSTEMS INC | | | SCAC4 |
| 31 | TUCU | TUCABI CONTAINER S.L. | | E | BIC |
| 32 | TUD | Flight Alaska, Inc. | Callsign: Tundra, Ceased operations on 05 March 2017. | USA | AVCODES |
| 33 | TUD | Flight Alaska | | | ICAO1 |
| 34 | TUDC | TUNISON, D C | | | SCAC4 |
| 35 | TUDI | TRUCK USA DIRECT INC | | | SCAC4 |
| 36 | TUDN | TRANS-POULIN LIMITED | | | SCAC4 |
| 37 | TUDR | TRANSPORTE RODRIGUEZ RODRIGUEZ INC | | | SCAC4 |
| 38 | TUEA | TNT USA EXPRESS INC | | | SCAC4 |
| 39 | TUEB | TROUT, TOM TRUCKING INC | | | SCAC4 |
| 40 | TUEE | TRUCO ENTERPRISES INC | | | SCAC4 |
| 41 | TUEK | TRUE TRUCKING | | | SCAC4 |
| 42 | TUEN | TRANSPORT GUIZMO-FLY | | | SCAC4 |
| 43 | TUEQ | TRUCKING USA ENTERPRISES INC | | | SCAC4 |
| 44 | TUF | American Aviation Services Ltd. | Callsign: Tuftyclub, | GB | AVCODES |
| 45 | TUFO | TRANSPORTES MARRUFO | | | SCAC4 |
| 46 | TUFP | TUFPORT INDUSTRIES LTD | | | SCAC4 |
| 47 | TUFU | TRANSUNIVERSE FORWARDING NV | | B | BIC |
| 48 | TUFV | TUF TRANSPORT SERVICE INC | | | SCAC4 |
| 49 | TUFY | TRANSPORTES UNIDOS DE NORTEAMERICA | | | SCAC4 |
| 50 | TUG | Turgai Avia Ltd | Callsign: Turgai Avia, | KZ | AVCODES |
| 51 | TUG | Government of Turkmenistan | Callsign: Turkmenistan Government, | TM | AVCODES |
| 52 | TUGB | TUGBOAT TRANSPORTATION LLC | | | SCAC4 |
| 53 | TUGG | TRAILER TUGGERS INC | | | SCAC4 |
| 54 | TUGW | TUG WELD MANUFACTURING | | | SCAC4 |
| 55 | TUGX | Texas Utilities Generating Co. | 1/1980; eliminated 1/1988; 1/1994 | | NAKINA |
| 56 | TUGX | Texas Utilities Mining Co. | added 1/1988; 1/1994-7/2000; eliminated 1/2002 | | NAKINA |
| 57 | TUGX | TXU Mining Co. | added 1/2002; 7/2005; eliminated 1/2008 | | NAKINA |
| 58 | TUGX | Luminant Mining | added 1/2008 | | NAKINA |
| 59 | TUGX | Texas Utilities Generating Co. | 1/80; eliminated 1/88; 1/94 | | NRHS |
| 60 | TUGX | Texas Utilities Mining Co. | added 1/88; 1/94-7/2000 | | NRHS |
| 61 | TUGX | *TXU MINING CO. [TEXAS UTILITIES MINING CO.; TEXAS UTILITIES GENERATING COMPANY] | | | PWRC |
| 62 | TUGX | +LUMINANT MINIMG | | | PWRC |
| 63 | TUGX | Texas Utilities Generating | | | RSRV |
| 64 | TUGX | LUMINANT | | | SCAC4 |
| 65 | TUHG | TRANS-PLUS EXPRESS J L INC | | | SCAC4 |
| 66 | TUI | Tuninter, S.A. | IATA: UG, IATA Prefix: 150, Name changed to Sevenair w.e.f. 07 July 2007. ICAO code SEN | TN | AVCODES |
| 67 | TUI | TUIfly GmbH | IATA: X3, Callsign: Tuifly, IATA Prefix: 617, Name changed from Hapag Lloyd Fluggessellschaft mbH, ICAO callsign changed from Hapag Lloyd. IATA designator changed from HF w.e.f. 01 October 2010. ICAO designator changed from HLF w.e.f. 01 October 2010. | D | AVCODES |
| 68 | TUI | Tuninter | IATA: UG | | ICAO1 |
| 69 | TUI | TUIfly | Real: TUI, X3 | D | TRAFFIC |
| 70 | TUIA | TRANSPRO USA INC | | | SCAC4 |
| 71 | TUIE | TRANSPORT ULTIMATE INC | | | SCAC4 |
| 72 | TUIN | TRANSPORTES URBINA INC | | | SCAC4 |
| 73 | TUIO | TURK'S MOTOR EXPRESS, INC | | | SCAC1 |
| 74 | TUIQ | TRANCASA USA INC | | | SCAC4 |
| 75 | TUJ | Tajouj Aviation | Callsign: Taja, | SUD | AVCODES |
| 76 | TUJM | TRANSPORTES EXPRESS CANTU | | | SCAC4 |
| 77 | TUJO | TRUJILLO TRANSFER | | | SCAC4 |
| 78 | TUK | New Island Connections, Inc. d/b/a Ocean Wings Commuter Service | Callsign: Tuckernuck, | USA | AVCODES |
| 79 | TUK | Trans European Airways (UK) Ltd. d/b/a TEA (UK) Ltd. | IATA: EQ, Callsign: Teastar, Ceased operations on 27 September 1991. | GB | AVCODES |
| 80 | TUK | Ocean Wings Commuter Service | | | ICAO1 |
| 81 | TUKC | TUCKER, J. A., COMPANY, INC. | | | SCAC1 |
| 82 | TUKC | TUCKER COMPANY WORLDWIDE INC | | | SCAC4 |
| 83 | TUKF | TOUBA TRUCKING LLC | | | SCAC4 |
| 84 | TUKG | TIPTON TRUCKING | | | SCAC4 |
| 85 | TUKI | TANGS TRUCKING | | | SCAC4 |
| 86 | TUKK | TACKETT TRUCKING LLC | | | SCAC4 |
| 87 | TUKN | TURKON LINE | | | SCAC4 |
| 88 | TUKR | TUCKER FREIGHT LINES INC. | | | PWRC |
| 89 | TUKR | TWINS TRUCKING | | | SCAC4 |
| 90 | TUKT | TUREK TRUCKING COMPANY | | | SCAC4 |
| 91 | TUKW | TUCKER, WOODY & | | | SCAC4 |
| 92 | TUL | Tulpar | Callsign: Ursal, AOC revoked by Russian Authorities | RUS | AVCODES |
| 93 | TUL | Tulpar Air | | | ICAO1 |
| 94 | TUL | Teplárna Ústí nad Labem, a.s. | | CZ | VKM |
| 95 | TULA | TULSA INC | | | SCAC4 |
| 96 | TULD | TRANSPORT UNLIMITED LLC | | | SCAC4 |
| 97 | TULE | TULGESTKA, E H & SONS INC | | | SCAC4 |
| 98 | TULED | Transports Urbans Lédoniens | | F | TRAFFIC |
| 99 | TULF | TRANSPORTATION USA LLC | | | SCAC4 |
| 100 | TULG | TULGESTKA TRANSPORT INC | | | SCAC4 |
