| smod | Stonehearth Mod Data |
| smpd | Sc2gears Mouse Print Data |
| smzip | Stepmania Package |
| sns | Burnout Paradise Sound |
| so3 | ScummVM MP3 Sound |
| sog | ScummVM OGG Sound |
| solitairesave-ms | Microsoft Solitaire Saved Game |
| sou | ScummVM Sound Data |
| sounds | Quake 3 Engine Sound Definition File |
| sow | Descent Archive |
| spc | Danganronpa V3 Game Archive |
| spidersolitairesave-ms | Microsoft Spider Solitaire Saved Game |
| spk | VGA Planets 4 Ship Pack |
| splane | Simple Planes Plane Data |
| sqf | Operation FlashPoint Function Script |
| sqh | Harbinger Game Data |
| sqs | Operation FlashPoint Script |
| srdi | Danganronpa V3 Model Data |
| srdv | Danganronpa V3 Image Data |
| srk | Sub Rosa Client File |
| srt0 | Wii Texture Animation |
| ss0 | Splinter Cell: Pandora Tomorrow Game Audio |
| ssf | Bioware Aurora Sound Set File |
| ssfrec | Super Smash Flash 2 Recording |
| ssfsav | Super Smash Flash Saved Game |
| ssh | Cricket 2005 Game Data |
| ssq | Dance Dance Revolution Song |
| stage | 2D Fighter Maker 2nd Stage Data |
| starpak | Titanfall 2 Game Archive |
| stsg | SuperTux Saved Game |
