Gastón Dalmau was born the youngest of three boys on 23 November 1983[1][2][3] in Coronel Suárez, Buenos Aires. He has two older brothers.[1] Dalmau cites Charly García as his idol and favourite singer[1][3] He also plays guitar .[3] Dalmau admires sports such as swimming, tennis and football,[1][3] and in football he supports Boca Juniors.[1][3] On September 24, 2019, he announced on his Instagram that he had obtained his US citizenship. He is openly gay, he is in a relationship with Spanish community manager José Navarro.[4]