Following the same methods used in Festival da Canção 2017, which resulted in Portugal winning the Eurovision Song Contest, broadcaster RTP invited 22 composers to present an original song. Salvador Sobral, the winner of Festival da Canção 2017, was given the opportunity to invite one extra composer. The other three entries in the selection were chosen through preselection competitions organized by public radio station Antena 1. One of these three composers, Daniela Onis, was chosen through a competition for songwriters without any record release prior to 15th September. The other two were selected out of 346 submissions, open to all Portuguese citizens or those currently living in Portugal. As in 2017, it will be up for the composers to decide which artists will perform their song.