Dan Altavilla was born and raised in Elizabeth, Pennsylvania where he attended Mercyhurst University, a Division II school in nearby Erie. As a sophomore, Altavilla played in the Cape Cod Baseball League for the Yarmouth-Dennis Red Sox. The following year, he posted a 9-1 record in 12 games for Mercyhurst. In 80 1⁄3 innings, Altavilla struckout a school record 129 batters .
Altavilla would go on to be drafted by the Seattle Mariners in the fifth round of the 2014 MLB Draft with the 141st pick.
His first two years as a professional were spent with the Everett Aquasox (A) in 2014 and the Bakersfield Blaze (A-Advanced) in 2015.