The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- MymeType (14 members)
- N3 (98 members)
- NYA (1 member)
- Nabisae (29 members)
- NacreMoon (31 members)
- Nadeko (12 members)
- Nakatsu (0 members)
- Namedude (7 members)
- Nanika (7 members)
- Nantai (182 members)
- Natl (58 members)
- Navbox templates (0 members)
- Navigation templates (10 members)
- Needs Documentation (0 members)
- Needs Information (259 members)
- Needs documentation (36 members)
- Nekhnona (3 members)
- Nexus0.10 (5 members)
- Nexus Worlds (18 members)
- Nightmare (6 members)
- Noahrav (11 members)
- Noildoof (136 members)
- Noindexed pages (10 members)
- NostAlgic (3 members)
- NostAlgic Characters (1 member)
- NostAlgic Guides (5 members)
- NostAlgic Locations (25 members)
- NostAlgic Nexus Worlds (4 members)
- NostAlgic Screenshots (4 members)
- Notice images (1 member)
- Notice templates (13 members)
- Novel Images (9 members)
- Nuaah (142 members)
- Nulsdodage (9 members)
- Octave (43 members)
- Olm (2 members)
- Oneirokamara (53 members)
- Onychophorum (3 members)
- Open for Cross-Author Connections (112 members)
- Openbreeze (7 members)
- Orchidmantis (50 members)
- Otoshi Takeuchi (8 members)
- Oudn (107 members)
- Ouri (26 members)
- OutlanderS3S (2 members)
- Oversomnia (6 members)
- Oversomnia Characters (1 member)
- Oversomnia Guides (5 members)
- Oversomnia Locations (60 members)
- Oversomnia Nexus Worlds (7 members)