The following categories exist on the wiki, and may or may not be unused. Also see wanted categories.
- Greece (31 members)
- Greenland (0 members)
- Grenada (1 member)
- Guatemala (7 members)
- Guyana (1 member)
- Haiti (2 members)
- Help (1 member)
- Heritage museums (1 member)
- Hidden categories (22 members)
- Hide breadcrumbs (0 members)
- Hide header (7 members)
- Hide langs (0 members)
- Hide redirect (2 members)
- Historical context (95 members)
- Historical events (85 members)
- Historical records (13 members)
- Historical regions (1 member)
- Honduras (2 members)
- Hong Kong (2 members)
- How-Genealogy tips (1 member)
- How-to-guides (0 members)
- How-to guides (25 members)
- HowGenealogy tips (0 members)
- How to (3 members)
- Hungary (13 members)
- Iceland (2 members)
- India (13 members)
- Indonesia (4 members)
- Interface images (4 members)
- Interface templates and forms (2 members)
- Iran (3 members)
- Iraq (2 members)
- Ireland (60 members)
- Isle of Man (1 member)
- Israel (21 members)
- Italian ethnicity (0 members)
- Italy (42 members)
- Jamaica (4 members)
- Japan (3 members)
- Jewish cemeteries (1 member)
- Jewish diaspora (24 members)
- Jewish genealogy (1 member)
- Jordan (1 member)
- Kazakhstan (2 members)
- Kosovo (2 members)
- Kyrgyzstan (1 member)
- Laos (1 member)
- Latin America (19 members)
- Latvia (5 members)
- Lebanon (1 member)