Frank Santo was born in Brooklyn, New York.
He held positions at the Church of Our Lady of Peace in Brooklyn and the Presbyterian Church of the Covenant in Manhattan before becoming director of music in 1981 at the Episcopal Church of the Holy Apostles in New York, a position he held until his death in 1992.
He was an active member of the New York City Chapter of the American Guild of Organists, serving on its executive board at the time of his death, and was a longtime member of the Association of Anglican Musicians.
He composed numerous sacred choral pieces, including many short antiphons, hymn descants and other liturgical items, anthems and motets. Among Santo's extended works are a Passion According to St. John and the Three Tenebrae Responsoria, written in 1985 and dedicated "to all those who have died of AIDS."
Although he was very ill with AIDS by April 1990 when the historic Casavant organ at Holy Apostles was destroyed in a fire, Santo headed the committee to find a new organ for the restored church, and was instrumental in the decision to sign a contract with Rosales Organ Builders for a 32-stop mechanical-action organ.
Frank Santo died of AIDS-related complications in New York at the age of 48.