| 1 | CLO | Litoral Airlines, Compania, (Colair) | Callsign: Colairline, | GQ | AVCODES |
| 2 | CLO | Challenge Aero Ukraine LLC | Callsign: Challenge Ukraine, | UA | AVCODES |
| 3 | CLOB | COLONIAL TOURS INC | | | SCAC3 |
| 4 | CLOC | CLADOR CARTAGE CORP | | | SCAC3 |
| 5 | CLOC | CONTINENTAL LOGISTICS LLC | | | SCAC4 |
| 6 | CLOC | Canadian Locomotive Company | | CDN | TRAFFIC |
| 7 | CLOE | CLOVERLEAF TANK LINES | | | SCAC3 |
| 8 | CLOE | CREATION LOBEL | | | SCAC4 |
| 9 | CLOF | COLONIAL FORWARDING COMPANY (A DIV | | | SCAC3 |
| 10 | CLOG | Capital Logistics | | GB | TRAFFIC |
| 11 | CLOH | C L A S S | | | SCAC3 |
| 12 | CLOI | COLONIAL OIL INDUSTRIES INC | | | SCAC3 |
| 13 | CLOI | CANAM LOGISTICS | | | SCAC4 |
| 14 | CLOK | CENTRAL LIQUOR CO | | | SCAC3 |
| 15 | CLOM | COLTONS MOVING & STORAGE INC | | | SCAC3 |
| 16 | CLOO | CLOONEN TRUCKING INC | | | SCAC3 |
| 17 | CLOP | CENTRAL TRANSPORT EXPRESS | | | SCAC3 |
| 18 | CLOQ | CALSOL INC | | | SCAC3 |
| 19 | CLOR | CLOVERLEAF TRANSPORTATION INC | | | SCAC3 |
| 20 | CLOS | COMPREHENSIV | | | SCAC4 |
| 21 | CLOT | CLOVER LANE TRANSPORTATION INC | | | SCAC3 |
| 22 | CLOU | SEACO SRL | | BDS | BIC |
| 23 | CLOU | CLOU CONTAINER LEASING GMBH | | | PWRC |
| 24 | CLOU | CLOU Container Leasing | | | RSRV |
| 25 | CLOU | CONTAINER LEASING AGENTUR GMBH | | | SCAC3 |
| 26 | CLOU | SEA CONTAINERS LTD | | | SCAC4 |
| 27 | CLOV | CLOVER ENTERPRISES | | | SCAC3 |
| 28 | CLOV | CLOVERDALE FUEL LTD | | | SCAC4 |
| 29 | CLOW | CALLOWAY OIL COMPANY | | | SCAC4 |
| 30 | CLOX | Clark Refining & Marketing, Inc. | 7/2000-7/2005 (not listed) | | NAKINA |
| 31 | CLOX | Canada Linseed Oil Mills, Ltd. | 7/1935-7/1954; eliminated 10/1955; added 1/1957; 10/1957-4/1961; eliminated 7/1965 | | NAKINA |
| 32 | CLOX | Canada Linseed Oil Mills, Ltd. | 4/38-4/61; eliminated 7/65 | | NRHS |
| 33 | CLOX | Clark Refining & Marketing, Inc. | Jul-00 | | NRHS |
| 34 | CLOX | *CANADA LINSEED OIL MILLS, LTD. | | | PWRC |
| 35 | CLOX | +CLARK REFINING & MARKETING, INC. | | | PWRC |
| 36 | CLOX | Clark Refining and Marketing | | | RSRV |
| 37 | CLOX | PREMCOR REFINING GROUP INC | | | SCAC4 |
| 38 | CLOY | COLE OIL CO INC | | | SCAC4 |
