| 1 | SOP | Solinair Latelsko Podjetjet d.o.o. | IATA: SP, Callsign: Solinair, IATA Prefix: 265, IATA designator changed to ZS. | SLO | AVCODES |
| 2 | SOP | Solinair Latelsko Podjetjet d.o.o. | IATA: ZS, Callsign: Solinair, IATA Prefix: 265, IATA designator changed from SP*. | SLO | AVCODES |
| 3 | SOP | Solinair | | | ICAO1 |
| 4 | SOPA | SOUTHERN PETROLEUM INC | | | SCAC4 |
| 5 | SOPC | SMOOTH OPERATORS INC | | | SCAC4 |
| 6 | SOPE | SOPERS | | | SCAC4 |
| 7 | SOPH | SOUTH PACIFIC SHIPPING COMPANY | | | SCAC1 |
| 8 | SOPH | SOUTH PACIFIC SHIPPING COMPANY LTD | | | SCAC4 |
| 9 | SOPI | SEAPORT PETROLEUM | | | SCAC4 |
| 10 | SOPJ | SOPGC | | | SCAC4 |
| 11 | SOPK | SO-PAK-CO INC | | | SCAC4 |
| 12 | SOPR | South Pierce R.R. | 1/1980-7/2005 | | NAKINA |
| 13 | SOPR | South Pierce R.R. | 1/80-7/2000 | | NRHS |
| 14 | SOPR | SOUTH PIERCE RAILROAD | | | PWRC |
| 15 | SOPR | South Pierce Railroad | | | RSRV |
| 16 | SOPV | STORMS OF PLEASURE | | | SCAC4 |
| 17 | SOPZ | SORG PAPER COMPANY | | | PWRC |