The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Sometimes a Great Notion (29 members)
- Soundtracks (16 members)
- Soundtracks (RDM) (10 members)
- Soundtracks (TOS) (3 members)
- Sources (57 members)
- Space-Mimic! (1 member)
- Space Croppers (50 members)
- Spaceball (46 members)
- Special Formating Templates (5 members)
- Special effects templates (2 members)
- Species (27 members)
- Species (TOS-RH) (1 member)
- Spoilers Templates (8 members)
- Sports (The Caprican) (14 members)
- Star of Kobol recipient (9 members)
- Steampunk Battlestar Galactica 1880 (17 members)
- Storyteller (7 members)
- Storyteller (RDM) (3 members)
- Stub Pages (631 members)
- Stub Templates (3 members)
- Subst Templates (35 members)
- TOC templates (3 members)
- TOS (1,415 members)
- TOS-DE (9 members)
- TOS-RH (36 members)
- TRS (321 members)
- TSC (10 members)
- TV Channels (5 members)
- Take the Celestra (41 members)
- Taking a Break From All Your Worries (28 members)
- Taking a Break from All Your Worries (1 member)
- Tales of the Pegasus - Chapter One: Daddy's Girl (1 member)
- Tauron (2 members)
- Technology (195 members)
- Technology (1980) (11 members)
- Technology (RDM) (92 members)
- Technology (TOS) (75 members)
- Technology (TRS) (10 members)
- Templates using Click-ext (1 member)
- Templates using ParserFunctions (81 members)
- Templates using click (6 members)
- Templates using titled-click (13 members)
- Templates using titled-click-ext (2 members)
- Temporarily undeleted pages (1 member)
- Terminology (211 members)
- Terminology (1980) (3 members)
- Terminology (RDM) (104 members)
- Terminology (TOS) (59 members)
- Terminology (TRS) (5 members)
- Terms of Use (1 member)