| 1 | ITC | International Air Carrier Association (IACA) | | B | AVCODES |
| 2 | ITC | International Air Carrier Association | | | ICAO1 |
| 3 | ITC | Norfolk Southern Ry. Co. (Norfolk Southern) | added 1/1991; 1/1994-7/2005 | | NAKINA |
| 4 | ITC | Norfolk and Western Ry. Co. | added 7/1982; eliminated 1/1991 | | NAKINA |
| 5 | ITC | Illinois Terminal R.R. Co. | 1/1941-10/1966 & 1/1975-1/1980; eliminated 4/1982 | | NAKINA |
| 6 | ITC | Illinois Terminal R.R. Co. | 1/52-10/66 & 1/75-1/80; eliminated 4/82 | | NRHS |
| 7 | ITC | Norfolk and Western Ry. Co. | added 7/82; eliminated 1/91 | | NRHS |
| 8 | ITC | Norfolk Southern Ry. Co. | added 1/91; 1/94-7/2000 | | NRHS |
| 9 | ITC | NORFOLK SOUTHERN RAILWAY [ILLINOIS TERMINAL RR; NORFOLK & WESTERN RAILROAD] | | | PWRC |
| 10 | ITC | Illinois Terminal Railroad (Norfolk Southern) | | | RSRV |
| 11 | ITC | ILLINOIS TERMINAL RAILROAD COMPANY | | | SCAC4 |
| 12 | ITCA | INSPECTECH ANALYGAS GROUP INC | | | SCAC4 |
| 13 | ITCD | INTERCITY DIRECT | | | SCAC4 |
| 14 | ITCF | INDEPENDENCE TRUCKING CORPORATION | | | SCAC4 |
| 15 | ITCG | INLAND TRAFFIC CONTROL INC | | | SCAC4 |
| 16 | ITCH | INTERNATIONAL TOUCH CONSOLIDATOR IN | | | SCAC4 |
| 17 | ITCK | INTERNATIONAL PAPER (HOUSTON CONTAI | | | SCAC4 |
| 18 | ITCL | INTERNACIONAL DE ELEVADORES SA DE C | | | SCAC4 |
| 19 | ITCM | INTERTRANS CARRIER COMPANY | | | SCAC4 |
| 20 | ITCN | IT CORPORATION | | | SCAC1 |
| 21 | ITCO | Island Terminal Company | | USA | TRAFFIC |
| 22 | ITCOKE | Italiana Coke | | I | TRAFFIC |
| 23 | ITCQ | IVRAJ TRANSPORT LTD | | | SCAC4 |
| 24 | ITCT | INTEGRA ADHESIVES INC | | | SCAC4 |
| 25 | ITCU | INTERCONTAINER S.A. | | E | BIC |
| 26 | ITCU | INTERCONTAINER | | | PWRC |
| 27 | ITCU | Intercontainer | | | RSRV |
| 28 | ITCV | ITC INTERNATIONAL | | | SCAC4 |
| 29 | ITCW | INFONET TECHNOLOGY CORPORATION | | | SCAC4 |
| 30 | ITCX | International Technologies Corp. | 7/2000-7/2005 (not listed) | | NAKINA |
| 31 | ITCX | Interstate Transport Co. | 7/1935-4/1961; eliminated 10/1963 | | NAKINA |
| 32 | ITCX | Interstate Transport Co. | 4/38-4/61 | | NRHS |
| 33 | ITCX | International Technologies Corp. | Jul-00 | | NRHS |
| 34 | ITCX | *INTERSTATE TRANSPORT CO. | | | PWRC |
| 35 | ITCX | +INTERNATIONAL TECHNOLOGIES CORPORATION | | | PWRC |
| 36 | ITCX | International Technologies Corporation | | | RSRV |
| 37 | ITCY | ILIAMNA TRANSPORTATION COMPANY LLC | | | SCAC4 |
| 38 | ITCZ | INTERCONTINENTAL TERMINALS COMPANY | | | PWRC |
