| AccoladeNA | Publisher | |
| AccoladePAL | Publisher | |
| According to Prophecy | Developer | |
| Accursed Toys | Developer | |
| Ace Maddox | DeveloperPublisher | |
| Ace Savaid | Developer | |
| Ace Software (Alan Cresswell) | Developer | |
| Ace Software (Alan P. Cresswell) | Developer | |
| Ace Team | Developer | |
| Ace of Wands | Developer | |
| AceMark | Developer | |
| AceOfAces | Developer | |
| Acemoisan | Developer | |
| Acer | Publisher | |
| Aces Games | Developer | |
| Achie | Developer | |
| Achromateam | Developer | |
| Acid | Developer | |
| Acid Nerve | Developer | |
| Acid Plan | DeveloperPublisher | |
| Acid Software | DeveloperPublisher | |
| Acid Wizard Studio | Developer | |
| Acid x Kitty | Developer | |
| AcidSpaceshipp | Developer | |
| AcidicDuck | Developer | |
| AcidosisProductions | Developer | |
| Ackk Studios | DeveloperPublisher | |
| Aclips | Developer | |
| Acme Animation | DeveloperPublisher | |
| Acme Interactive | Developer | |
| Acme Interactive Productions | Developer | |
| Acme Nerd Games | Developer | |
| Aconitum Games | Developer | |
| Acony | Developer | |
| Acorn Software | Publisher | |
| Acquire | DeveloperPublisher | |
| Acquire Corp | Publisher | |
| AcroPR | Developer | |
| Acropolise | Developer | |
| Acrosicious | Developer | |
| Acroviu | Developer | |
| Act Japan | Developer | |
| Actainment | Developer | |
| Actawesome | Developer | |
| Acti-Art | DeveloperPublisher | |
| Action 53 | Developer | |
| Action Button | Developer | |
| Action Forms | Developer | |
| Action Graphics | Developer | |
| Action Software | Publisher | |