Sobral was born in Lisbon and has lived there most of his life. He was born into a formerly noble family, the son of Salvador Luís Cabral Braamcamp Sobral and Luísa Maria Cabral Posser Vilar. His paternal grandparents are Salvador José de Almeida Braamcamp Sobral and Maria Elisa Perestrelo de Matos de Figueiredo Cabral; and his maternal grandparents are João Luís Posser de Andrade Vilar and Luísa Maria de Melo Breyner Freire Cabral. The politician Hermano José Braamcamp de Almeida Castelo Branco is his great-great-great-great-grandfather.
At the age of ten, he participated in the TV programme Bravo Bravíssimo, and at 20 he was one of the ten finalists of Ídolos, the Portuguese version of the Idols franchise. As a finalist, he sang music by Stevie Wonder, Leonard Cohen and Rui Veloso.
He studied Psychology at the
Instituto Superior de Psicologia Aplicada , in Lisbon. He spent time in Mallorca as an Erasmus student, where he sang in bars.
Salvador Sobral is a fan of Chet Baker and bossa nova singers including Caetano Veloso and Chico Buarque. He speaks five languages: Portuguese, Spanish, English, a little Italian and Catalan.