| 5301 | TKCX | Thiele Kaolin Co. | added 4/1968; 4/1970-7/2005; eliminated 4/2006 | | NAKINA |
| 5302 | TKCX | Thiele Kaolin Co. | added 4/68; 4/70-7/2000 | | NRHS |
| 5303 | TKCX | *KOSTER CO. | | | PWRC |
| 5304 | TKCX | *THIELE KAOLIN COMPANY | | | PWRC |
| 5305 | TKCX | Thiele Kaolin | | | RSRV |
| 5306 | TKCY | TRUCKING COMPANY LLC, THE | | | SCAC4 |
| 5307 | TKDT | TRAM K-D TRUCKING CORP | | | SCAC4 |
| 5308 | TKDY | TECHNIMARK DE REYNOSA SA DE CV | | | SCAC4 |
| 5309 | TKE | Trek Airways | Callsign: Trekair, | ZA | AVCODES |
| 5310 | TKE | Trek Airways (Pty) Ltd. | IATA: JW, Callsign: Trekair, | ZA | AVCODES |
| 5311 | TKE | Take Air Line | | | ICAO1 |
| 5312 | TKEA | TRI TRUCK CENTRE INC | | | SCAC4 |
| 5313 | TKED | THUNDER K ENTERPRISES LLC | | | SCAC4 |
| 5314 | TKEG | TOLER, KENT TRUCKING | | | SCAC4 |
| 5315 | TKEK | TEREK OIL | | | SCAC4 |
| 5316 | TKEL | TURK ENTERPRISES LTD | | | SCAC4 |
| 5317 | TKEM | TRANSPORTES KEMSA SA DE CV | | | SCAC4 |
| 5318 | TKEN | Tennken R.R. Co., Inc. | added 4/1984; 1/1994-7/2005 | | NAKINA |
| 5319 | TKEN | Tennken R.R. Co., Inc. | added 4/84; 1/94-7/2000 | | NRHS |
| 5320 | TKEN | TENNKEN RAILROAD CO., INC. | | | PWRC |
| 5321 | TKEN | Tennken Railroad | | | RSRV |
| 5322 | TKEO | TRIPLE K EXPRESS COMPANY | | | SCAC4 |
| 5323 | TKEP | TRUCKERS EXPRESS, INC. | | | SCAC1 |
| 5324 | TKEQ | TRUCK LEASING OF BROOKLYN INC | | | SCAC4 |
| 5325 | TKER | TESSENDERLO KERLEY INC | | | SCAC4 |
| 5326 | TKES | TK EXPRESS LLC | | | SCAC4 |
| 5327 | TKET | TRUCKING ENTERPRISES LLC | | | SCAC4 |
| 5328 | TKEY | TURKEY HILL SUGARBUSH LTD | | | SCAC4 |
| 5329 | TKEZ | T & K EVANS GRAIN, INC. | | | PWRC |
| 5330 | TKF | UK Royal VIP Helicopter Flights | Callsign: Rainbow, ICAO designator changed from TQF. | GB | AVCODES |
| 5331 | TKFG | TEAK FURNITURE GALLERY | | | SCAC4 |
| 5332 | TKFI | TRUCK FREIGHT INTERNATIONAL LTD | | | SCAC4 |
| 5333 | TKFN | TRIFISK MFG INC | | | SCAC4 |
| 5334 | TKFO | THERMO KING FRESNO INC | | | SCAC4 |
| 5335 | TKFR | TIMS TRUCKING | | | SCAC4 |
| 5336 | TKFT | TASK FORCE TIPS INC | | | SCAC4 |
| 5337 | TKGC | TANKSKIBSREDE | | | SCAC4 |
| 5338 | TKGE | TRUCKGO & CO | | | SCAC4 |
| 5339 | TKGFT | Thyssen Krupp Gft Gleistechnik Gmbh | | DE | VKM |
| 5340 | TKGK | THANK GOD TRUCK INC | | | SCAC4 |
| 5341 | TKGN | TECCO TRUCKING INC | | | SCAC4 |
| 5342 | TKGO | TK MOLD & ENGINEERING INC | | | SCAC4 |
| 5343 | TKGP | TRK GROUP, THE | | | SCAC4 |
| 5344 | TKGQ | TEANECK LOGISTICS INC | | | SCAC4 |
| 5345 | TKGR | TRUCKING R US INC | | | SCAC4 |
| 5346 | TKHI | TURKISH EXPRESS LINE INC | | | SCAC4 |
| 5347 | TKHT | TAKHAR TRANSPORTATION LLC | | | SCAC4 |
| 5348 | TKHU | TRANSPORTKUHLUNG THERMO KING GMBH | | | SCAC4 |
| 5349 | TKI | Turku Air Oy | Callsign: Turku Air, | FIN | AVCODES |
| 5350 | TKIA | T & K NATIONWIDE TRUCKING INCORPROA | | | SCAC4 |
| 5351 | TKIB | TRANS KNIGHTS INC | | | SCAC4 |
| 5352 | TKIC | THOMAS, K INC | | | SCAC4 |
| 5353 | TKID | TRUSSTEK INC | | | SCAC4 |
| 5354 | TKIE | TRANSROCKIES INC | | | SCAC4 |
| 5355 | TKIF | TICK INC | | | SCAC4 |
| 5356 | TKIG | TORTILLA KING INC | | | SCAC4 |
| 5357 | TKIK | TRANSPORTES KIKI | | | SCAC4 |
| 5358 | TKIL | TROIKA INTERNATIONAL LTD | | | SCAC4 |
| 5359 | TKIQ | TRANSPORT KN INC | | | SCAC4 |
| 5360 | TKIU | TOM KRAEMER, INC. | | USA | BIC |
| 5361 | TKIV | TRANSPORT KARANVIR INC | | | SCAC4 |
| 5362 | TKJ | Tarkim Ucak Bakim Onarim ve Havacilik Ltd STI. | Callsign: Tarkim, | TR | AVCODES |
| 5363 | TKJN | TEKLENBURG, JOHN INTERNATIONAL INC | | | SCAC4 |
| 5364 | TKK | Aero Ways, Inc. | Callsign: Tarka, | USA | AVCODES |
| 5365 | TKKA | TWO K (2K) TRANSPORTATION | | | SCAC4 |
| 5366 | TKKE | TRUCK-KO ENTERPRISE | | | SCAC1 |
| 5367 | TKKI | TK TRUCKING | | | SCAC4 |
| 5368 | TKKR | T K TRUCKING | | | SCAC4 |
| 5369 | TKKU | TRUKAI INDUSTRIES LTD | | PNG | BIC |
| 5370 | TKL | Taraz Air, Aircompany | Callsign: Sarisy, | KZ | AVCODES |
| 5371 | TKLD | TRUCK LOAD CARRIERS OF TONAWANDA IN | | | SCAC4 |
| 5372 | TKLE | TRACK LOGISTICS INC | | | SCAC4 |
| 5373 | TKLI | TRICKLINIE INC | | | SCAC4 |
| 5374 | TKLJ | T I M TRUCK LINE INC | | | SCAC4 |
| 5375 | TKLK | TRANSK LOGISTICS INC | | | SCAC4 |
| 5376 | TKLO | TRUCK LOGISTICS INC | | | SCAC4 |
| 5377 | TKLP | TKL COMPANY | | | SCAC4 |
| 5378 | TKLS | T L S INC | | | SCAC4 |
| 5379 | TKLS | Thyssen Krupp GFT Gleistechnik GmbH | | DE | VKM |
| 5380 | TKLU | TANK LEASING COMPANY | | USA | BIC |
| 5381 | TKLU | TURKISH CARGO LINES | | | SCAC4 |
| 5382 | TKLV | TRUCK LOAD SERVICES INC | | | SCAC4 |
| 5383 | TKLY | T & K LOGISTICS INC | | | SCAC4 |
| 5384 | TKM | JM Family Aviation | Callsign: Tacoma, ICAO designator changed tfrom TQM | USA | AVCODES |
| 5385 | TKMC | TRACKIM INC | | | SCAC4 |
| 5386 | TKME | TUCKER, MIKE | | | SCAC4 |
| 5387 | TKMI | TANK MANAGEMENT INC | | | SCAC4 |
| 5388 | TKMK | TRANSPORTES RONCALLI LOLEK SA DE CV | | | SCAC4 |
| 5389 | TKML | TOOKES, MILTON C TRUCKING | | | SCAC4 |
| 5390 | TKMLT | ThyssenKrupp Materials d.o.o., Inđija | | RS | VKM |
| 5391 | TKMN | TRUCKMEN CORPORATION | | | SCAC4 |
| 5392 | TKMQ | TRUCKIM INC | | | SCAC4 |
| 5393 | TKMS | TRANSPORT KEMAL BILMEZ INC | | | SCAC4 |
| 5394 | TKMU | TANKMASTER LTD | | RUS | BIC |
| 5395 | TKNF | TRACKIN FAST INC | | | SCAC4 |
| 5396 | TKNH | TURMOIL TRUCKING LLC | | | SCAC4 |
| 5397 | TKNI | TORKELSON COMMODITIES INC | | | SCAC4 |
| 5398 | TKNK | TOMPKINS TRUCKING | | | SCAC4 |
| 5399 | TKNO | TORO TRUCKING | | | SCAC4 |
| 5400 | TKNU | THERMO KING TRANSPORT KOELING B.V. | | NL | BIC |
