| 1 | CHI | Cougar Helicopters, Inc. | Callsign: Cougar, | CDN | AVCODES |
| 2 | CHI | Cougar Helicopters | | | ICAO1 |
| 3 | CHI | Chichibu Railway | | J | TRAFFIC |
| 4 | CHIA | CHINATRANS INTERNATIONAL LIMITED | | | SCAC4 |
| 5 | CHIB | CHARLO INC | | | SCAC3 |
| 6 | CHIB | CHICAGO LOGISTIC SERVICE INC | | | SCAC4 |
| 7 | CHICAGO | | City: Chicago | USA | TRAFFIC |
| 8 | CHICAR | Carabineros de Chile | | RCH | TRAFFIC |
| 9 | CHID | CHILDS MOVING & STORAGE INC | | | SCAC3 |
| 10 | CHIE | CHRISTIANSEN, R E TRUCKING INC | | | SCAC3 |
| 11 | CHIF | CHIEFTAIN EXPRESS, INC | | | SCAC3 |
| 12 | CHIG | CHAR-LO INC | | | SCAC3 |
| 13 | CHIH | CHARMER INDUSTRIES INC | | | SCAC3 |
| 14 | CHIHNAN | Chihnan Bus Company, Ltd | City: Taipei | RC | TRAFFIC |
| 15 | CHIK | CHICKASAW MOTOR LINE | | | SCAC3 |
| 16 | CHIK | Chiba Kotsu Co. | Owned by the Keisei Group | J | TRAFFIC |
| 17 | CHIL | CHILDRESS TRANSPORT | | | SCAC3 |
| 18 | CHIL | Chiltern Railways Ltd. | Real: CR, 1999: 269km standard gauge, not electrified Chiltern Railways is a train operating company in England. It was formed by the privatisation of British Rail in 1996 and it operates train mainline services from Marylebone station in London, to Aylesbury and Birmingham Snow Hill. Initially the line was franchised to a company formed by the British Rail managers of the route, but since 2003 has been a wholly owned subsidiary of Laing Rail, who owned a much smaller shareholding at privatisation. In 2002 a new 20 year franchise began which promises significant investment in the route. | GB | TRAFFIC |
| 19 | CHIM | CHIPMAN CORPORATION | | | SCAC3 |
| 20 | CHIN | CHICAGO INDIANA RAILWAY | | | PWRC |
| 21 | CHIO | CHICAGO TRIBUNE | | | SCAC3 |
| 22 | CHIO | CHILOS TRUCKING | | | SCAC4 |
| 23 | CHIP | CHIPPEWA MOTOR FRT INC | | | PWRC |
| 24 | CHIP | CHIPS EXPRESS INC | | | SCAC4 |
| 25 | CHIQ | CHIPPEWA VALLEY TRANSPORTATION CO I | | | SCAC3 |
| 26 | CHIQ | CHEMAS INTERNACIONAL S DE RL DE CV | | | SCAC4 |
| 27 | CHIS | CHICKALOON SERVICE | | | SCAC3 |
| 28 | CHIS | CHICKALOON SERVICE | | | SCAC4 |
| 29 | CHITA | Chita Noriai Co. (Chita Bus) | | J | TRAFFIC |
| 30 | CHITOSE | Chitose Sougo Kanko Bus | | J | TRAFFIC |
| 31 | CHIU | TEXTAINER EQUIPMENT MANAGEMENT LTD | | BM | BIC |
| 32 | CHIU | CHIMCO - BULGARIA | | | PWRC |
| 33 | CHIU | Chimco | | | RSRV |
| 34 | CHIU | CAPITAL LEASE LTD | | | SCAC4 |
| 35 | CHIV | CHILTON MOVING & STORAGE | | | SCAC3 |
| 36 | CHIV | C H I OVERHEAD DOORS INC | | | SCAC4 |
| 37 | CHIW | CHILEAN LINE INC | | | PWRC |
| 38 | CHIW | CHILEAN LINES INC | | | SCAC3 |
| 39 | CHIW | COMPANIA SUD AMERICANA DE VAPORES S | | | SCAC4 |
| 40 | CHIX | Consolidated Holdings Co., Inc. | added 4/1975; 1/1980; eliminated 1/1983 | | NAKINA |
| 41 | CHIX | Chicago Tank Car Co. | 7/1930-7/1935 | | NAKINA |
| 42 | CHIX | Consolidated Holdings Co., Inc. | added 4/75; 1/80; eliminated 1/83 | | NRHS |
| 43 | CHIX | *CHICAGO TANK CAR CO. | | | PWRC |
| 44 | CHIX | *CONSOLIDATED HOLDINGS CO. INC. | | | PWRC |
| 45 | CHIZ | CHAHALIS INDUSTRY | | | PWRC |
