Ernesto de Sousa's estate has an acknowledged artistic, historical and cultural value and is partially based in the following institutions:
National Library of Portugal (collection of writings and memorabilia).
Archive of Photographic Documentation of the DGPC (photographs from the 1940s and 1950s).
Cinemateca Portuguesa-Cinema Museum / ANIM (films and videos).
Photographic archive of Câmara Municipal de Lisboa (photographic slides mostly related to cultural heritage and contemporary art).
Ethnology Museum (works by Franklin Vilas Boas Neto from Ernesto de Sousa's collection).
National Museum of Contemporary Art–Museu do Chiado [MNAC] (works by Ernesto de Sousa).
State Secretariat for Culture art collection (works by Ernesto de Sousa).
Calouste Gulbenkian Foundation (work by other authors from Ernesto de Sousa's collection).
The Berardo Collection (Ernesto de Sousa's poster collection).
The remaining estate owned by his family consists of:
Library: books on art, poetry, cinema, theater, essays, philosophy, history, politics, fiction; art catalogs and magazines (Portuguese and foreign).
Photography and slides: works by Ernesto de Sousa or elements from his mixed-media works.
Sound recordings: elements from his mixed-media works, interviews with Almada Negreiros and round tables, original music by Jorge Peixinho.
Video and mixed-media: videos from the 1960s and 1970s, mixed-media projects submitted by applicants for the Ernesto de Sousa Fellowship (1989-2005).
Documental collection: files relating to studies by Ernesto de Sousa on Almada Negreiros and to the exhibition "Alternativa Zero", among others.
Artworks: collection of works by artists from the 1940s to the 1980s.
Mail art and artist books.