| 1 | SIC | Air Sicilia S.p.A. | IATA: BM, Callsign: Air Sicilia, Ceased operations during 2004. Name changed from Air Sicilia S.R.L. | I | AVCODES |
| 2 | SIC | Air Sicilia S.R.L. | IATA: BM, Callsign: Air Sicilia, Name changed to Air Sicilia S.p.A. | I | AVCODES |
| 3 | SICC | SIX ZERO THREE SIX SIX FIVE ONE (60 | | | SCAC4 |
| 4 | SICD | SPECTRAN, INC | | | SCAC1 |
| 5 | SICF | SLOAN IMPLEMENT COMPANY | | | SCAC4 |
| 6 | SICG | SICKLER'S TRUCKING | | | SCAC4 |
| 7 | SICH | STORM INTERSTATE CO | | | SCAC4 |
| 8 | SICJ | SILVER CITY ALUMINUM CORP | | | SCAC4 |
| 9 | SICL | SILVER CITY LUMBER INC | | | SCAC4 |
| 10 | SICO | SIMPSON EXPRESS AND TRANSFER INC | | | SCAC4 |
| 11 | SICR | SCHAKE INDUSTRIES INC | | | SCAC4 |
| 12 | SICT | SV TRUCKING SERVICES LLC | | | SCAC4 |
| 13 | SICU | SHANGHAI XURONG CONTAINERCO., LTD | | PRC | BIC |
| 14 | SICU | SIC PROCESSING GMBH | | | SCAC4 |
| 15 | SICW | SICOMSA | | | SCAC4 |
| 16 | SICX | Sloss Industries Corp. | added 7/1988; 1/1994-7/2000; eliminated 1/2005; 7/2005 (not listed) | | NAKINA |
| 17 | SICX | Sloss Industries Corp. | added 7/88; 1/94-7/2000 | | NRHS |
| 18 | SICX | SLOSS INDUSTRIES CORPORATION | | | PWRC |
| 19 | SICX | Sloss Industries Corporation | | | RSRV |
| 20 | SICX | SLOSS INDUSTRIES CORPORATION | | | SCAC4 |
