| Abbreviation | Designation | |
|---|---|---|
| s | Seitengang (German) | classification |
| AT-S | Salzburg, Land Salzburg (German) | country code |
| 74 / SE | Sverige, Konungariket Sverige (Swedish) Sweden, Kingdom of Sweden | country code |
| SE-S | Värmland, Värmlands län (Swedish) | country code |
| S | S-tog København (Danish) Copenhagen S-train | train category |
| SB | Schnellbahn (German) | train category |
| S | Stadtschnellbahn (S-Bahn) (German) Commuter train | train category |
| S | Stuttgart Hbf, Landeshauptstadt Stuttgart (German) | fare point / vehicle registration plate |
| S | Sveg (Swedish) | station code |
| S | RB Saarbrücken, Regionalbereich Saarbrücken (German) RB Saarbrucken | railway administration |
| 25 / S | BD Saarbrücken (1953–1994), Bundesbahndirektion Saarbrücken (German) | railway administration |