Steven Koller was born in New York and raised in Dallas, Texas. His mother, a New Yorker, is a homemaker, and his father, a native Austrian, is a home builder. He swam, ran track, and joined the drama club at Jesuit Prep in Dallas. He graduated from Webster University in Vienna, Austria, with a BA in International Relations. He was a founding member of his college's theater club, and elected to its student council. He has one brother and two sisters.