In 1924, Findlay was selected to the U.S. soccer team which competed in the 1924 Summer Olympics.

Following its elimination from the Olympics, the U.S. played one exhibition game, a 3–3 tie with Poland.

Following the Olympics, he signed with the New York Nationals of the American Soccer League.

[7] William's family emigrated to the United States from Scotland in around 1914, when he was 10 years old.

His father was Scottish international soccer player Robert Findlay, and his uncle Tom Findlay was also a professional;[8] the brothers played together for Kilmarnock, Motherwell and Port Glasgow Athletic during their careers.