The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Active Talk Pages (10 members)
- Active for Squadron 42 (11 members)
- Active production (2 members)
- Add-ons (10 members)
- Adir images (6 members)
- Administration and sales centers (1 member)
- Administrators (1 member)
- Advertisement (0 members)
- Advocacy Archive (0 members)
- Advocacy Faction Characters (1 member)
- Aegis Dynamics (53 members)
- Aelanna Tesla Images (32 members)
- Aeroview Hangars (1 member)
- Agricultural supplies (4 members)
- Ail'ka System (10 members)
- Alejo Brothers (7 members)
- Alien Languages (1 member)
- Alien Races (6 members)
- Alien language templates (5 members)
- Alloys (4 members)
- Always Forward (0 members)
- Amon and Reese Co. (19 members)
- Angeli (1 member)
- Angeli images (1 member)
- Animus Missile Launcher (1 member)
- Animus Missile Launcher images (3 members)
- Anti-aircraft turrets (1 member)
- Anti-personnel mines (1 member)
- Anti-personnel turrets (1 member)
- Anvil Aerospace (32 members)
- AopoA (0 members)
- Aopoa (5 members)
- Apache License (5 members)
- Apartment Habs (4 members)
- Apocalypse Arms (15 members)
- Apocalypse Arms images (1 member)
- Apollo Images (2 members)
- Apollo Medivac images (16 members)
- Apollo Triage images (16 members)
- Apollo series (2 members)
- Aponte Explorer images (1 member)
- Appliance manufacturers (1 member)
- Appointment Missions (4 members)
- April Fool's (5 members)
- Ar (0 members)
- Ar-2 (0 members)
- ArcCorp (21 members)
- ArcCorp (planet) (1 member)
- ArcCorp AO Missions (13 members)
- ArcCorp images (29 members)