E-Primatur is a Portuguese publishing platform that brings books to readers through a combination of editorial publishing, online retail and reader-supported projects. Its catalogue spans classic and contemporary literature, poetry, theatre, history, cultural studies and essays, with works by authors including Winston Churchill, Franz Kafka, Sigrid Undset, Machado de Assis and Joseph Conrad. Books are released under several imprints, including E-Primatur, Livro B, Bicho-do-Mato and BookBuilders.

Readers can support proposed titles before publication. Each project explains the individual contribution required, the total support target and the voting deadline. If a project proceeds, supporters receive the book without additional charges, at a price described as around two-thirds of its usual bookstore cost; if the target is not met, supporters can choose whether to request a refund or keep their contribution for a future project. E-Primatur also sells completed titles through its online shop, including editions exclusive to its website and events. The platform reports hundreds of completed books and offers readers a direct role in helping shape its publishing programme.