| 1 | IOS | Isles of Scilly Skybus Ltd. | IATA: 5Y, Callsign: Scillonia, Designator 5Y* recalled by IATA. IATA designator changed from FW | GB | AVCODES |
| 2 | IOS | Isles of Scilly Skybus Ltd. | IATA: FW, Callsign: Scillonia, IATA designator changed to 5Y* | GB | AVCODES |
| 3 | IOS | Isles of Scilly Skybus Ltd. | Callsign: Scillonia, Designator 5Y* recalled by IATA. IATA designator changed from FW | GB | AVCODES |
| 4 | IOS | Isles of Scilly Skybus | | | ICAO1 |
| 5 | IOSC | INTEROCEAN STEAMSHIP CORPORATION, S | | | SCAC4 |
| 6 | IOSF | IOSCO TRUCKING INC | | | SCAC4 |
| 7 | IOSX | Interstate Oil Shippers Line | 7/1923 | | NAKINA |
| 8 | IOSX | *INTERSTATE OIL SHIPPERS LINE | | | PWRC |
| 9 | IOSX | *INDIANA & OHIO SCENIC RAIL CORP. | | | PWRC |
