Denomination: American Ethical Union
Auchincloss was the son of Edgar Stirling Auchincloss (1847–1892) and Maria LeGrange Sloan. His uncles were Hugh Dudley Auchincloss (father of Hugh D. Auchincloss, Jr.) and John Winthrop Auchincloss (grandfather of Louis Auchincloss).
- He engaged in financial and stock brokerage business in New York City 1908-1940. He was a governor of the New York Stock Exchange from 1921 to 1938.