| Uneasy Game Studios | Developer | |
| Unenthullte | Developer | |
| Unenthuser | Developer | |
| Unepic Games | Publisher | |
| Unept | Developer | |
| UnevenPixelStudios | Developer | |
| Unexpected Development | Developer | |
| Unexpected Developments | Developer | |
| Unfinished Games | Developer | |
| Unfinished Pixel | DeveloperPublisher | |
| UnfinishedCircl | Developer | |
| Unfold Games | Developer | |
| Unforgotten | Developer | |
| Unformed | Developer | |
| Unfurl Games | Developer | |
| Ungrateful Dead | Developer | |
| Unholy_thoughts | Developer | |
| Uni Post Company Ltd | Publisher | |
| UniDot Studio | Developer | |
| UniGlow Entertainment | Developer | |
| Unibear Studio | Developer | |
| Unico | DeveloperPublisher | |
| Unico Electronics | Publisher | |
| Unicube | Developer | |
| Unicube Studios | Developer | |
| UnidayStudio | Developer | |
| Unidub | Developer | |
| Unimatrix Productions | Developer | |
| Union Logic | Developer | |
| Union Logic Software Publishing | Publisher | |
| Unipacc | Publisher | |
| Unique | Publisher | |
| Unique Development Studios | Developer | |
| Unisonshift | DeveloperPublisher | |
| Unistellar Industries, LLC | DeveloperPublisher | |
| Unit 4 Games | Developer | |
| Unit DTH Studios | DeveloperPublisher | |
| Unit02Games | Developer | |
| Unite Studios | Developer | |
| Unitech | Developer | |
| United Coders | Developer | |
| United Dreams | Developer | |
| United Front Games | Developer | |
| United Game Artists | DeveloperPublisher | |
| United Independent Entertainment | Publisher | |
| United Label | Publisher | |
| Unites | Publisher | |
| Unity Games | Publisher | |
| Unity Games Japan | Publisher | |
| Unity Ninja | Developer | |