In December 2021, Galdames was included in the senior national team call-up by Gerardo Martino for a friendly match against Chile set to take place on December 8.[3] He had also been called up for Chile by the coach Martín Lasarte, but he rejected that chance.[4]
From his paternal line, he is the younger brother of the Chilean footballers Pablo Jr. and Thomas[5] and the half-brother of the also footballer Mathías.[7][8] In addition, through his maternal line, he and his brothers are related to the Spanish footballer Nerea Sánchez Millán.[9]