| 1 | OTVA | ONE TWO SEVEN ZERO ZERO FOUR NINE ( | | | SCAC4 |
| 2 | OTVB | ORLEANS TRAVEL BUREAU INC | | | SCAC3 |
| 3 | OTVC | ON TIME SERVICES INC | | | SCAC3 |
| 4 | OTVD | OLYMPIC TRANSPORTATION SERVICES | | | SCAC4 |
| 5 | OTVE | ON TIME SERVICIOS CONSOLIDADOS SA D | | | SCAC4 |
| 6 | OTVR | Otter Tail Valley R.R. Co., Inc. | added 4/1987; 1/1994; eliminated 10/1999; 7/2000-7/2005 | | NAKINA |
| 7 | OTVR | Otter Tail Valley R.R. Co., Inc. | added 4/87; 1/94; eliminated 10/99; 7/2000 | | NRHS |
| 8 | OTVR | OTTER TAIL VALLEY RAILROAD CO., INC. (RAIL AMERICA) | | | PWRC |
| 9 | OTVR | Otter Tail Valley Railroad (Genesee & Wyoming) | | | RSRV |
| 10 | OTVR | OTTERTAIL VALLEY RAILROAD CO INC | | | SCAC3 |
| 11 | OTVS | ONE THREE SEVEN SEVEN ZERO SIX SEVE | | | SCAC4 |
