| 1 | SWO | Swiss World Airways, S.A. | IATA: SO, Callsign: Swissworld, Ceased operations during 1998 | CH | AVCODES |
| 2 | SWO | Suriname International Victory Airline N.V. | Callsign: Siva, | SME | AVCODES |
| 3 | SWO | Surninam International Victory Airline | | | ICAO1 |
| 4 | SWO | Stadtwerke Osnabrück | City: Osnabrück | D | TRAFFIC |
| 5 | SWO | Stadtwerke Osnabrück AG | | DE | VKM |
| 6 | SWOA | SWIFT TRANSPORTATION COMPANY INC (O | | | SCAC4 |
| 7 | SWOF | SWINOMISH FISH COMPANY | | | SCAC4 |
| 8 | SWOI | STATE WOOD INC | | | SCAC4 |
| 9 | SWOJ | SALT WORKS | | | SCAC4 |
| 10 | SWOK | FORMERLY SOUTHWESTERN OKLAHOMA RAILROAD | | | PWRC |
| 11 | SWOL | SUN WEST OIL LLC | | | SCAC4 |
| 12 | SWON | STINSON, WO AND SON LTD | | | SCAC4 |
| 13 | SWOV | SWAN TRANSPORTATION SERVICES LTD | | | SCAC4 |
| 14 | SWOX | Swan Oil Co., Inc. | 7/1937 (not listed) | | NAKINA |
| 15 | SWOX | SWAN OIL CO., INC. | | | PWRC |
| 16 | SWOY | SOUTHWESTERN OIL COMPANY | | | SCAC4 |
