Levitt was born into a Jewish family who were originally immigrants from Russia and Austria, his grandfather was from eastern Europe.
William Jaird was born on February 11, 1907 in Brooklyn, New York. William Levitt's father, Abraham Levitt, was the son of a poor rabbi who immigrated from Eastern Europe. Abraham Levitt left school at age 10, but educated himself. At the age of 20 he entered law school, specializing in real estate law. He married Pauline Biederman in 1906. Five years later the couple had another son, Alfred Stuart. As a child, William Levitt would put on a suit, run into the living room and announce his plans to go to Manhattan to make money and live well.