| Shadow Planet Productions |
| Shin'en |
| Shiny Entertainment |
| Shockwave Productions |
| Shrapnel Games |
| Sidhe Interactive |
| Sierra |
| Sierra Northwest |
| Sierra Studios |
| Sigil Games |
| Signal Studios |
| Silent Dreams |
| Silicon Dreams |
| Silicon Garage Arts |
| Silicon Knights |
| Silicon Studio |
| Silver Creek Entertainment |
| Silver Wish Games |
| SilverBirch Studio |
| Silverlode Interactive |
| SimBin |
| Similis |
| Simon and Schuster Interactive |
| Sir-Tech Canada |
| Sirius Games |
| Sixteen Tons Entertainment |
| Ska Studios |
| SkyFallen Entertainment |
| Slant Six Games |
| Slapdash |
| Sledgehammer Games |
| Slick Entertainment |
| Slightly Mad Studios |
| Slitherine |
| Smart Bomb Interactive |
| SmartCell Technology |
| Smilebit |
| Snail Games |
| Sniper Studios |
| SNK Playmore |
| Snowberry Connection |
| Snowbird Game Studios |
| Snowblind Studios |
| Soldak Entertainment |
| Sonalysts |
| Sonic Powered Co. |
| Sonic Team |
| Sony Bend |
| Sony Computer Entertainment |
| Sony Online Entertainment |
| Sora Ltd. |
| SouthEnd Interactive |
| SouthPeak Interactive |
| souvenir circ. |
| Spark Unlimited |
| SpellBound |
| Spicy Horse |
| SpiderMonk |
| Spiderweb Software |
| Spike |
