The Atlantic sawtail catshark is found from Cape St. Vincent in southwestern Portugal, through the Strait of Gibraltar into the Alborán Sea, to as far as Cabo de Gata in southwestern Spain. It is most abundant in the center of the Alborán Sea, and around Isla de Alborán. This species has been recorded a few times off Morocco and once off Mauritania; it may be extremely rare or mistaken for G. melastomus in the region. Its total range has been estimated to encompass , about evenly divided between the northeastern Atlantic and the western Mediterranean.