| Startup Go!Go! | |
| STAX Ltd | Saitama |
| Stellar Craft, Inc. | Tokyo |
| Step Technica Co., Ltd | |
| STING | Tokyo |
| STK Technology Co., Ltd | |
| StockGraphy, Inc. | |
| Storm Producer by ITC | Tokyo |
| Strategic Co., Ltd | Aichi |
| StrategyCore Co., Ltd | Tokyo |
| Strive | Tokyo |
| Structural Design Strategy Co., Ltd | Tokyo |
| Studio Bros Co., Ltd | Tokyo |
| Studio Co., Ltd | Tokyo |
| Studio Karen Co., Ltd | Tokyo |
| Studio Sakai, Inc. | Tokyo |
| Studio51 Co., Ltd | Tokyo |
| StudioZ Co., Ltd | Tokyo |
| Sugino Fashion College | |
| Sugino Gakuen | |
| Sugiyama Jogakuen | |
| Sumco Corporation | Tokyo |
| SUMI Kougyo Co., Ltd | |
| Sumire Gakuen | |
| Sumitomo Bakelite Co., Ltd | Tokyo |
| Sumitomo Corporation | |
| Sumitomo Electric Industries Ltd | |
| Sumitomo Mitsui Financial Group | |
| Sumitomo Mitsui Trust Investment Co., Ltd | |
| Sumitomo Pharma Co., Ltd | |
| Summit Pharmaceuticals International Corporation | |
| Sun Internet Co., Ltd | Tokyo |
| Sun Techno College | |
| Sun* | |
| Sun-Wa Technos Corporation | |
| Sunbit System Co., Ltd | Tokyo |
| SunBridge Co., Ltd | Tokyo |
| Suncad | Tokyo |
| Suneight Investment Co., Ltd | Tokyo |
| Sunfield Internet | Tokyo |
| Sunnet Co., Ltd | Tokyo |
| Sunnet Corporation | Tokyo |
| Sunrise System Co., Ltd | Tokyo |
| SunShine Internet | Tokyo |
| Super Studio Co., Ltd | Tokyo |
| Supership, Inc. | Tokyo |
| SuperSoftware Co., Ltd | Osaka |
| Supre Co., Ltd | Tokyo |
| Surfboard.jp | Fukui |
| Surpass Industry Co., Ltd | Saitama |