| Siberian Entertainment | Developer | |
| SiberianGriever | Developer | |
| Sibling Rivalry Games | Developer | |
| Sicerat | Developer | |
| Sick Chicken Studios | Developer | |
| Sick Puppies | Developer | |
| SickLion | Developer | |
| SicklyGeek | Developer | |
| Sid | Developer | |
| Sid Bostwick | Developer | |
| Sid Fish Games | Developer | |
| Sid Meier | Developer | |
| Sidaal | Developer | |
| SiddSaxena | Developer | |
| Siddarth R Govindan | Developer | |
| Side Group | Developer | |
| Side Hit Studios | DeveloperPublisher | |
| Side Kick LTD | Developer | |
| SideCo | Developer | |
| SideQuest | Developer | |
| SideQuest Studios | Developer | |
| SideUpDown | Developer | |
| Sidebar Games | DeveloperPublisher | |
| Sidhe | DeveloperPublisher | |
| Sidhe Interactive | Developer | |
| Siduron | Developer | |
| Sieber2210 | Developer | |
| Sieg | DeveloperPublisher | |
| Siegfried Croes | Developer | |
| Siegfried Kurtz | Developer | |
| Sienna Blossom | Developer | |
| Sierra | DeveloperPublisher | |
| Sierra Attractions | Publisher | |
| Sierra Entertainment | DeveloperPublisher | |
| Sierra EntertainmentEU | Publisher | |
| Sierra EntertainmentEU,NA | Publisher | |
| Sierra EntertainmentPAL | Publisher | |
| Sierra Entertainment|Universal Interactive | Publisher | |
| Sierra Northwest | Developer | |
| Sierra On-Line | DeveloperPublisher | |
| Sierra On-line | DeveloperPublisher | |
| Sierra Online | DeveloperPublisher | |
| Sierra Sports | Publisher | |
| Sierra Studios | DeveloperPublisher | |
| SierraLee | Developer | |
| SierraVenture | Publisher | |
| Siesta | Developer | |
| Siff | Developer | |
| Sigeria | Developer | |
| SigilCipher | Developer | |