The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- STFU memes (1 member)
- Sarawak templates (1 member)
- Science (6 members)
- Scientists (3 members)
- Scribunto modules with errors (5 members)
- Search engines (1 member)
- Segregationists (1 member)
- Separatist states (6 members)
- Settler-colonial states (7 members)
- Settler colonialism (7 members)
- Settler colonialism (essays) (1 member)
- Sexism (2 members)
- Sign languages (1 member)
- Sino-Soviet split (1 member)
- Slave owners (5 members)
- Slavery (7 members)
- Slogans (11 members)
- Slogans in China (1 member)
- Slogans in the USSR (1 member)
- Slogans of the Communist Party of China (1 member)