The Viscount of Estoi is a noble title in Portugal, associated with the civil parish of Estoi in the Algarve region. The title was created in the 19th century and is part of the Portuguese nobility, reflecting the historical significance of the area. The title is often linked to the House of Estoi, which has played a role in the local history and culture. The viscountcy is a hereditary title, passed down through generations, and represents the aristocratic heritage of Portugal.