| 1 | NSX | Niagara Smelting Corp. | 7/1930-1/1946 | | NAKINA |
| 2 | NSX | Niagara Smelting Corp. | Apr-38 | | NRHS |
| 3 | NSX | *NIAGARA SMELTING CO. | | | PWRC |
| 4 | NSX | *NORFOLK SOUTHERN CORPORATION | | | PWRC |
| 5 | NSXI | NORTHSTAR EXPRESS INC | | | SCAC3 |
| 6 | NSXI | NSX INC | | | SCAC4 |
| 7 | NSXJ | NON STOP XPRESS | | | SCAC4 |
| 8 | NSXO | NS TRANSPORT | | | SCAC4 |
| 9 | NSXP | NORTH STATE EXPRESS INC | | | SCAC4 |
| 10 | NSXR | NINETY SIX (96) EXPRESS INC | | | SCAC3 |
| 11 | NSXS | NEW SOUTH EXPRESS INC | | | SCAC3 |
| 12 | NSXS | NEW SOUTH EXPRESS INC | | | SCAC4 |
| 13 | NSXU | NORFOLK SOUTHERN CORPORATION | | | SCAC4 |
| 14 | NSXZ | NORFOLK SOUTHERN RAILWAY COMPANY | | | PWRC |
| 15 | NSXZ | Norfolk Southern Railway | | | RSRV |
| 16 | NSXZ | NORFOLK SOUTHERN RAILWAY COMPANY (N | | | SCAC4 |
