| 501 | CAIU | CONCEPT CARGO INC | | | SCAC3 |
| 502 | CAIU | CAI INTERNATIONAL | | | SCAC4 |
| 503 | CAIV | CHARLESTON ALUMINUM TRANSPORTATION | | | SCAC4 |
| 504 | CAIX | Cominco American, Inc. | added 4/1966; 10/1966-1/1980; eliminated 5/1983 | | NAKINA |
| 505 | CAIX | Cominco American, Inc. | added 4/66; 10/66-1/80; eliminated 5/83 | | NRHS |
| 506 | CAIX | COMINCO AMERICAN, INC. | | | PWRC |
| 507 | CAIZ | CON AGRA INDUSTRIES | | | PWRC |
| 508 | CAJ | Cougar Air, Inc. | Callsign: Cougar Air, | CDN | AVCODES |
| 509 | CAJ | Air Caraibes Atlantique | Callsign: Car Line, Longhaul subsidiary of Air Caraibes | GP | AVCODES |
| 510 | CAJ | Air Caraibes Atlantique | | | ICAO1 |
| 511 | CÅJ | Kristianstad - Åhus Järnväg | 1886 - 1906 | S | svenska-lok.se |
| 512 | CAJA | CRESCENT AIR & SEA TRANSPORT SERVIC | | | SCAC3 |
| 513 | CAJC | CALLAHAN BROTHERS | | | SCAC3 |
| 514 | CAJC | CAJU S A DE C V | | | SCAC4 |
| 515 | CAJE | CACILHAS, JOE | | | SCAC4 |
| 516 | CAJG | C & J CARTAGE CO | | | SCAC3 |
| 517 | CAJH | CALKINS, JOHN TRUCKING | | | SCAC4 |
| 518 | CAJI | C & J TRANSPORT INC | | | SCAC3 |
| 519 | CAJK | CARTER, JACK | | | SCAC3 |
| 520 | CAJL | CALTON TRUCK SERVICE | | | SCAC4 |
| 521 | CAJN | CADENA AREVALO, JUAN MANUEL | | | SCAC4 |
| 522 | CAJO | CALUMET TRUCKING CO | | | SCAC3 |
| 523 | CAJO | CASTRO ADAMS, JESUS ARMANDO | | | SCAC4 |
| 524 | CAJQ | C & J TRUCKING INC | | | SCAC3 |
| 525 | CAJQ | COOPER, ALLAN J | | | SCAC4 |
| 526 | CAJR | CARJO TRUCKING INC | | | SCAC3 |
| 527 | CAJR | CAJUN EQUIPMENT SERVICES LLC | | | SCAC4 |
| 528 | CAJS | CARSTENS, J S | | | SCAC3 |
| 529 | CAJU | CAI INTERNATIONAL | | USA | BIC |
| 530 | CAJV | CARDINAL CARRIERS INC | | | SCAC4 |
| 531 | CAJY | CARLLEY, JAY INC | | | SCAC3 |
| 532 | CAK | Congo Air | | BS | AVCODES |
| 533 | CAK | County Air Services Ltd. | Callsign: County, | GB | AVCODES |
| 534 | CAK | Southwest Aircraft Charter LC | Callsign: Cactus, | USA | AVCODES |
| 535 | CAK | Congo Air | | | ICAO1 |
| 536 | CAKB | CAMPBELL, T J CONSTRUCTION COMPANY | | | SCAC4 |
| 537 | CAKD | CEDAR AIR TRANSFER INC | | | SCAC4 |
| 538 | CAKE | CALIFORNIA LUCKY ENTERPRISES INC | | | SCAC4 |
| 539 | CAKF | CARLTON TRUCKING | | | SCAC4 |
| 540 | CAKG | CLAIR TRUCKING | | | SCAC3 |
| 541 | CAKG | CONTAINER KING | | | SCAC4 |
| 542 | CAKI | C & K TRUCKING INC | | | SCAC3 |
| 543 | CAKI | CHAMBERS TRUCKING LLC | | | SCAC4 |
| 544 | CAKJ | C & A TRUCKING INC | | | SCAC3 |
| 545 | CAKL | CAPE TANK LINES INC | | | SCAC4 |
| 546 | CAKM | C & K MOVING & STORAGE INC | | | SCAC3 |
| 547 | CAKN | COLLINS & AIKMAN CORPORATION | | | SCAC3 |
| 548 | CAKN | COMPASS TRUCKING | | | SCAC4 |
| 549 | CAKO | CARR TRUCKING INC | | | SCAC3 |
| 550 | CAKP | CAPROCK PIGGYBACK SERVICE | | | SCAC3 |
| 551 | CAKR | CANAMA TRADING S DE R L | | | SCAC4 |
| 552 | CAKT | CADLE TRUCKING LLC | | | SCAC4 |
| 553 | CAKU | CAMELLIA LINE CO LTD | | J | BIC |
| 554 | CAKW | CAPRI ALFA | | | SCAC3 |
| 555 | CAKY | CAL-KY PIPE LINE COMPANY | | | SCAC3 |
| 556 | CAL | China Airlines | IATA: CI, Callsign: Dynasty, IATA Prefix: 297, | RC | AVCODES |
| 557 | CAL | Capitol Airways | IATA: CP, Callsign: Capitol, Ceased operations | GB | AVCODES |
| 558 | CAL | China Airlines | IATA: CI | | ICAO1 |
| 559 | CAL | China Airlines | | RC | TRAFFIC |
| 560 | CALA | The Carolina Southern R.R. Co. | added 7/1997; 7/2000; eliminated 10/2002; 7/2005 | | NAKINA |
| 561 | CALA | The Carolina Southern R.R. Co. | added 7/97; 7/2000 | | NRHS |
| 562 | CALA | CAROLINA SOUTHERN RAILROAD | | | PWRC |
| 563 | CALA | Carolina Southern Railroad | | | RSRV |
| 564 | CALA | CAROLINA SOUTHERN RAILROAD COMPANY, | | | SCAC4 |
| 565 | CALB | CAMEO LIMOUSINE SERVICE INC | | | SCAC3 |
| 566 | CALB | CALA INVESTMENTS LLC | | | SCAC4 |
| 567 | CALC | CALIFORNIA CARTAGE CO | | | SCAC3 |
| 568 | CALC | CALIFORNIA CARTAGE CO LLC | | | SCAC4 |
| 569 | CALD | CALDWELL FREIGHT LINES, INC | | | SCAC3 |
| 570 | CALD | CALDWELL FREIGHT LINES, INC | | | SCAC4 |
| 571 | CALE | CART-ALL EXPRESS INC | | | SCAC4 |
| 572 | CALF | CALIFORNIA TANK LINES, INC | | | SCAC3 |
| 573 | CALF | CALIFORNIA TANK LINES INC | | | SCAC4 |
| 574 | CALG | CALLAHAN GEO F | | | SCAC3 |
| 575 | CALGARY | | City: Calgary | USA | TRAFFIC |
| 576 | CALH | CALHOUN TRUCKING COMPANY INC | | | SCAC3 |
| 577 | CALI | CALIFORNIA MOVING & STORAGE | | | SCAC3 |
| 578 | CALI | CASCADE AGRONOMICS LLC | | | SCAC4 |
| 579 | CALJ | CAL-ARK INC | | | SCAC3 |
| 580 | CALJ | CALARK INC | | | SCAC4 |
| 581 | CALMR | Calgary Municipial Railway | | CDN | TRAFFIC |
| 582 | CALO | CORTEZ, ALFREDO | | | SCAC4 |
| 583 | CALP | CAL-PACIFIC TRUCK LINES, INC | | | SCAC3 |
| 584 | CALP | CALIPER EXPRESS | | | SCAC4 |
| 585 | CALR | CALIFORNIA FRESNO TRANSPORTATION CO | | | SCAC4 |
| 586 | CALS | CAPORE, L TRUCKING INC | | | SCAC3 |
| 587 | CALS | CARGO ALLIANCE SERVICE | | | SCAC4 |
| 588 | CALT | CALIFORNIA MOTOR TRANSPORT CO | | | SCAC3 |
| 589 | CALT | The Chicago and Alton R.R. Co. | Real: CA | USA | TRAFFIC |
| 590 | CALU | CALBERSON INTERNATIONAL | | | SCAC3 |
| 591 | CALU | RABANCO COMPANIES | | | SCAC4 |
| 592 | CALV | CALVIN, ART & SONS | | | SCAC3 |
| 593 | CALW | CALIFORNIA WAREHOUSE CO | | | SCAC3 |
| 594 | CALW | CALAWAY CO INC | | | SCAC4 |
| 595 | CALX | California Railcar Corp. | added 7/1979; 1/1980-7/2000; eliminated 1/2003; added 1/2004; eliminated 4/2004; 7/2005 (not listed) | | NAKINA |
| 596 | CALX | Calhoun Trading Co., Inc. | added 10/1974; 1/1975; eliminated 7/1976 | | NAKINA |
| 597 | CALX | American Cyanamid Co. | added 4/1954; 7/1954; eliminated 1/1957 | | NAKINA |
| 598 | CALX | American Cyanamid Co., Calco Chemical Division | added 10/1953; eliminated 4/1954 | | NAKINA |
| 599 | CALX | Calco Chemical Division, American Cyanamid Co. | 1/1941-1/1952; eliminated 10/1953 | | NAKINA |
| 600 | CALX | The Calco Chemical Co., Inc. | 7/1923-4/1938 | | NAKINA |
