| 9901 | SSFX | Southern States Phosphate & Fertilizer Co. | 4/61-7/65; eliminated 4/66 | | NRHS |
| 9902 | SSFX | SOUTHERN STATES PHOSPHATE & FERTILIZER CO. | | | PWRC |
| 9903 | SSFY | SERVICE STAR FREIGHTWAYS INC | | | SCAC4 |
| 9904 | SSFZ | TRAC LEASE INC | | | SCAC4 |
| 9905 | SSG | Slovak Government Flying Service | Callsign: Slovak Government, | SK | AVCODES |
| 9906 | SSG | Slovak Government Flying Service | | | ICAO1 |
| 9907 | SSGA | SAFE AND SOUND EQUINE | | | SCAC4 |
| 9908 | SSGD | SLING SHOT DELIVERY SERVICE | | | SCAC4 |
| 9909 | SSGE | SUN STATE TRUCKING LLC | | | SCAC4 |
| 9910 | SSGL | S & S ENERGY | | | SCAC4 |
| 9911 | SSGM | SCOTT STREET GREENHOUSES LIMITED | | | SCAC4 |
| 9912 | SSGN | S & S TRUCKING INC | | | SCAC4 |
| 9913 | SSGO | SAIPAN SHIPPING CO INC | | | SCAC4 |
| 9914 | SSGQ | SAM SAM THE DRAPERY MAN | | | SCAC4 |
| 9915 | SSGS | S T S GUIDING SERVICES LTD | | | SCAC4 |
| 9916 | SSGT | SCALETTA SAND & GRAVEL LTD | | | SCAC4 |
| 9917 | SSGU | SURGUTNEFTEGAS PJSC | | RUS | BIC |
| 9918 | SSGV | SECURITY STORAGE & VAN CO LLC | | | SCAC4 |
| 9919 | SSGW | S & S TRUCKING OF CATAWBA INC | | | SCAC4 |
| 9920 | SSGX | Sand Springs Home—Gasoline Dept. | 7/1930-7/1932 | | NAKINA |
| 9921 | SSGX | South Soo Grain Co. | added 11/1973; 1/1975-1/1980; eliminated 5/1983 | | NAKINA |
| 9922 | SSGX | McMaster Grain Co. | added 5/1983; eliminated 4/1990 | | NAKINA |
| 9923 | SSGX | South Soo Grain Co. | added 11/73; 1/75-1/80; eliminated 5/83 | | NRHS |
| 9924 | SSGX | McMaster Grain Co. | added 5/83; eliminated 4/90 | | NRHS |
| 9925 | SSGX | *SAND SPRINGS HOME, GASOLINE DEPT. | | | PWRC |
| 9926 | SSGX | *McMASTER GRAIN CO. [SOUTH SOO GRAIN CO.] | | | PWRC |
| 9927 | SSGX | McMaster Grain | | | RSRV |
| 9928 | SSH | Valley Air Services Inc. d/b/a Heritage Flight | Callsign: Snowshoe, Name changed to Heritage Aviaiton, Inc. d/b/a Heritage Flight | USA | AVCODES |
| 9929 | SSH | Heritage Aviaiton, Inc. d/b/a Heritage Flight | Callsign: Snowshoe, Name changed from Valley Air Services Inc. d/b/a Heritage Flight | USA | AVCODES |
| 9930 | SSH | Heritiage Flight (Valley Air Services) | | | ICAO1 |
| 9931 | SSH | South Shore | 1/1975 & 1/1994-7/2005 | | NAKINA |
| 9932 | SSH | South Shore | 1/75 & 1/94-7/2000 | | NRHS |
| 9933 | SSH | SOUTH SHORE RAILROAD | | | PWRC |
| 9934 | SSH | South Shore Railroad | | | RSRV |
| 9935 | SSHB | SEAARLAND SHIPMANAGEMENT (HAMBURG) | | | SCAC4 |
| 9936 | SSHC | STEWARTS SHOPS CORP | | | SCAC4 |
| 9937 | SSHD | SOUTH SHORE TRADING CO LTD | | | SCAC4 |
| 9938 | SSHG | SPRINGFIELD SHIPPING CO PANAMA SA | | | SCAC4 |
| 9939 | SSHH | SIMPSON HOTSHOT TRANSPORT | | | SCAC4 |
| 9940 | SSHI | SEASHELL SHIPOWNER S A | | | SCAC4 |
| 9941 | SSHL | SALMONS SPECIALIZED HAULING INC | | | SCAC4 |
| 9942 | SSHM | SURE SHOT FREIGHT SYSTEMS | | | SCAC4 |
| 9943 | SSHN | SUN SHINE EXPRESS | | | SCAC4 |
| 9944 | SSHO | SITINAS SHIPPING COMPANY S A | | | SCAC4 |
| 9945 | SSHP | SLINGSHOT EXPRESS | | | SCAC4 |
| 9946 | SSHQ | STRACHAN SHIPPING | | | PWRC |
| 9947 | SSHQ | SONY SUPPLY CHAIN SOLUTIONS | | | SCAC4 |
| 9948 | SSHR | Správa státních hmotných rezerv | | CZ | VKM |
| 9949 | SSHS | STRATTON SHUTTLE SERVICE INC | | | SCAC4 |
| 9950 | SSHT | SURESHOT TRANS INC | | | SCAC4 |
| 9951 | SSHU | SHRUTI MARINE SERVICES | | IND | BIC |
| 9952 | SSHW | SOMERSE | | | SCAC4 |
| 9953 | SSHX | Sharon Steel Hoop Co. | 7/1923-7/1932 | | NAKINA |
| 9954 | SSHX | *SHARON STEEL HOOP CO. | | | PWRC |
| 9955 | SSHX | *SOUTHERN SHORE | | | PWRC |
| 9956 | SSHY | SHORE AND SHORE HOLDINGS LLC | | | SCAC4 |
| 9957 | SSI | Superior International Airlines | Callsign: Super Jet, | WAN | AVCODES |
| 9958 | SSI | Vision Airlines | | | ICAO1 |
| 9959 | SSI | (NATX) RETIRED 06-11-92 - CUSTOMER SERVICE DIVISION | | | PWRC |
| 9960 | SSIA | SARNIA SHIPPING AGENCY, SARNIA ON | | | SCAC4 |
| 9961 | SSIC | SAMSEL SERVICES COMPANY | | | SCAC4 |
| 9962 | SSID | SSI EXPRESS | | | SCAC4 |
| 9963 | SSIE | SWISS STEEL INTERNATIONAL CANADA IN | | | SCAC4 |
| 9964 | SSIF | SERRA SHIPPING INC | | | SCAC4 |
| 9965 | SSIF | Societa Subaplina Imprese Ferroviarie | | I | TRAFFIC |
| 9966 | SSIF | Società Subalpina di Imprese Ferroviarie | | IT | VKM |
| 9967 | SSII | SOUTHERN STAR INDUSTRIES INC | | | SCAC4 |
| 9968 | SSIK | S & S TRUCKING INC | | | SCAC4 |
| 9969 | SSIL | SOLISTICS | | | SCAC4 |
| 9970 | SSIM | STARLINE SOLUTIONS INC | | | SCAC4 |
| 9971 | SSIP | SMITH SALES INC | | | SCAC4 |
| 9972 | SSIR | SSI EXPRESS INC | | | SCAC4 |
| 9973 | SSIS | SAN SIMEON STAGES INC | | | SCAC4 |
| 9974 | SSIU | JAPAN LINE, LTD. | | | PWRC |
| 9975 | SSIU | Japan Line Limited | | | RSRV |
| 9976 | SSIV | SCHILLI SPECIALIZED INC | | | SCAC4 |
| 9977 | SSIX | The Standard Silicate Co. | 7/1930-7/1932 | | NAKINA |
| 9978 | SSIX | Standard Silicate Co. (General American Tank Car Corp.) | added 11/1934; 7/1935 | | NAKINA |
| 9979 | SSIX | SSI Rail Corp. | added 4/1977; eliminated 1/1978 | | NAKINA |
| 9980 | SSIX | Itel Corp., Rail Division | added 1/1978; 1/1980; eliminated 4/1987 | | NAKINA |
| 9981 | SSIX | Itel Rail Corp. | added 4/1987; eliminated 10/1992 | | NAKINA |
| 9982 | SSIX | General Electric Railcar Services Corp. | added 10/1992; 1/1994; eliminated 1/2000 | | NAKINA |
| 9983 | SSIX | General Electric Rail Services Corp. | added 1/2000; 7/2000-7/2005 | | NAKINA |
| 9984 | SSIX | SSI Rail Corp. | eliminated 1/78 | | NRHS |
| 9985 | SSIX | Itel Corp., Rail Division | added 1/78; 1/80; eliminated 4/87 | | NRHS |
| 9986 | SSIX | Itel Rail Corp. | added 4/87; eliminated 10/92 | | NRHS |
| 9987 | SSIX | General Electric Railcar Services Corp. | added 10/92; 1/94; eliminated 1/2000 | | NRHS |
| 9988 | SSIX | General Electric Rail Services Corp. | added 1/2000; 7/2000 | | NRHS |
| 9989 | SSIX | *STANDARD SILICATE CO. | | | PWRC |
| 9990 | SSIX | +(NATX) (GENERAL ELECTRIC RAIL SERVICES CORP. [ITEL RAIL CORP.; SSI RAIL CORP.] | | | PWRC |
| 9991 | SSIX | *SOUTH EAST SHORELINE, INC. | | | PWRC |
| 9992 | SSIX | Itel Corporation | | | RSRV |
| 9993 | SSIX | GENERAL ELECTRIC RAILCAR SERVICES C | | | SCAC4 |
| 9994 | SSIZ | *(SSIU) SSI CONTAINER CORPORATION | | | PWRC |
| 9995 | SSIZ | *JAPAN LINE LIMITED | | | PWRC |
| 9996 | SSIZ | Japan Line Limited | | | RSRV |
| 9997 | SSJ | Krasavia, State Enterprise of Krasnoyarsk Territory | IATA: K9, Callsign: Siberian Sky, Designator K9 recalled by IATA | RUS | AVCODES |
| 9998 | SSJ | Krasavia, State Enterprise of Krasnoyarsk Territory | IATA: KI, Callsign: Siberian Sky, Designator KI recalled by IATA. Founded in 1956 as part of Aeroflot. Became independent in 1992. | RUS | AVCODES |
| 9999 | SSJ | Krasavia, State Enterprise of Krasnoyarsk Territory | Callsign: Siberian Sky, Name changed to Krasavia, Joint-Stock Company. Designator KI recalled by IATA. Founded in 1956 as part of Aeroflot. Became independent in 1992. | RUS | AVCODES |
| 10000 | SSJ | Krasavia, Joint-Stock Company | IATA: KV, Callsign: Siberian Sky, Name changed from Krasavia, State Enterprise of Krasnoyarsk Territory. Designator KI recalled by IATA. Founded in 1956 as part of Aeroflot. Became independent in 1992. | RUS | AVCODES |
