After the war, he returned to Nebraska and worked as the branch manager of a financial services institution in Fremont. He founded Exon Office Supplies (later Exon's Inc.) in Lincoln in 1953 and served as its president until 1971. In 1972, when Esso (Standard Oil Company of New Jersey) changed its name to Exxon, the Secretary of State of Nebraska declined to register the name due to the existence of Exon's Inc. Exon later claimed that he received an unspecified settlement from Exxon in exchange for renaming his business the J.J. Exon Company.