Charles attended Kents Hill School, graduating in June 1869. At first, he set his sights on a career in the Navy. Obtaining a midshipman's warrant, he entered the United States Naval Academy at Annapolis, where he graduated second in the class of 1873. He served as a naval officer until 1881, when he resigned in order to join his father's company. Naval service shaped Deering by exposing him to the cultures of Europe and Asia. He supplemented these experiences with extensive personal travel, developing cosmopolitan tastes, a cosmopolitan outlook, and a particular affinity with the arts of Spain. While still in the Navy, Charles met and married Ana Rogers Case, the daughter of Rear Admiral Augustus Ludlow Case; the couple wed in 1875 in Newport, Rhode Island. Ana Deering died October 31, 1876, shortly after giving birth to a son, Charles Case Deering (1876–1924).