| 1 | SSI | Superior International Airlines | Callsign: Super Jet, | WAN | AVCODES |
| 2 | SSI | Vision Airlines | | | ICAO1 |
| 3 | SSI | (NATX) RETIRED 06-11-92 - CUSTOMER SERVICE DIVISION | | | PWRC |
| 4 | SSIA | SARNIA SHIPPING AGENCY, SARNIA ON | | | SCAC4 |
| 5 | SSIC | SAMSEL SERVICES COMPANY | | | SCAC4 |
| 6 | SSID | SSI EXPRESS | | | SCAC4 |
| 7 | SSIE | SWISS STEEL INTERNATIONAL CANADA IN | | | SCAC4 |
| 8 | SSIF | SERRA SHIPPING INC | | | SCAC4 |
| 9 | SSIF | Societa Subaplina Imprese Ferroviarie | | I | TRAFFIC |
| 10 | SSIF | Società Subalpina di Imprese Ferroviarie | | IT | VKM |
| 11 | SSII | SOUTHERN STAR INDUSTRIES INC | | | SCAC4 |
| 12 | SSIK | S & S TRUCKING INC | | | SCAC4 |
| 13 | SSIL | SOLISTICS | | | SCAC4 |
| 14 | SSIM | STARLINE SOLUTIONS INC | | | SCAC4 |
| 15 | SSIP | SMITH SALES INC | | | SCAC4 |
| 16 | SSIR | SSI EXPRESS INC | | | SCAC4 |
| 17 | SSIS | SAN SIMEON STAGES INC | | | SCAC4 |
| 18 | SSIU | JAPAN LINE, LTD. | | | PWRC |
| 19 | SSIU | Japan Line Limited | | | RSRV |
| 20 | SSIV | SCHILLI SPECIALIZED INC | | | SCAC4 |
| 21 | SSIX | The Standard Silicate Co. | 7/1930-7/1932 | | NAKINA |
| 22 | SSIX | Standard Silicate Co. (General American Tank Car Corp.) | added 11/1934; 7/1935 | | NAKINA |
| 23 | SSIX | SSI Rail Corp. | added 4/1977; eliminated 1/1978 | | NAKINA |
| 24 | SSIX | Itel Corp., Rail Division | added 1/1978; 1/1980; eliminated 4/1987 | | NAKINA |
| 25 | SSIX | Itel Rail Corp. | added 4/1987; eliminated 10/1992 | | NAKINA |
| 26 | SSIX | General Electric Railcar Services Corp. | added 10/1992; 1/1994; eliminated 1/2000 | | NAKINA |
| 27 | SSIX | General Electric Rail Services Corp. | added 1/2000; 7/2000-7/2005 | | NAKINA |
| 28 | SSIX | SSI Rail Corp. | eliminated 1/78 | | NRHS |
| 29 | SSIX | Itel Corp., Rail Division | added 1/78; 1/80; eliminated 4/87 | | NRHS |
| 30 | SSIX | Itel Rail Corp. | added 4/87; eliminated 10/92 | | NRHS |
| 31 | SSIX | General Electric Railcar Services Corp. | added 10/92; 1/94; eliminated 1/2000 | | NRHS |
| 32 | SSIX | General Electric Rail Services Corp. | added 1/2000; 7/2000 | | NRHS |
| 33 | SSIX | *STANDARD SILICATE CO. | | | PWRC |
| 34 | SSIX | +(NATX) (GENERAL ELECTRIC RAIL SERVICES CORP. [ITEL RAIL CORP.; SSI RAIL CORP.] | | | PWRC |
| 35 | SSIX | *SOUTH EAST SHORELINE, INC. | | | PWRC |
| 36 | SSIX | Itel Corporation | | | RSRV |
| 37 | SSIX | GENERAL ELECTRIC RAILCAR SERVICES C | | | SCAC4 |
| 38 | SSIZ | *(SSIU) SSI CONTAINER CORPORATION | | | PWRC |
| 39 | SSIZ | *JAPAN LINE LIMITED | | | PWRC |
| 40 | SSIZ | Japan Line Limited | | | RSRV |
