Elder McKay received a Bachelor of Arts degree in English from Brigham Young University in 1984. In 1987, he received a juris doctor degree from Brigham Young University. From 1987 to 2018, Elder McKay practiced law in Oregon and Utah.

Elder McKay has served in a number of Church callings, including full-time missionary in the Japan Kobe Mission, elders quorum president, ward Young Men president, high councilor, counselor in a bishopric, bishop, counselor in a stake presidency and stake president.

Kyle Stirland McKay was born in Chicago, Illinois, on February 14, 1960. He married Jennifer Stone in 1984. They are the parents of nine children.