Documentary Channels
BBC
Mass media, public broadcasting
BBC Four
Culture, current affairs
BBC Earth
Nature and wildlife documentaries
BBC Parliament
Parliamentary and legislative programs
Sky Crime
Sky Nature
Sky History
Sky Arts
Sky Documentaries
Arts including, theatrical performances, movies, documentaries and music
History and society documentary
Investigation and justice documentary
Documentary and historical fiction series
Nature and wildlife documentary
Netflix
Very inclusive, lots different category
Amazon Prime
no specific category for documentary