Reva Beck Bosone was born on 2 April 1895 to Christian Mateus Beck and Zilpha Chipman Beck, who managed the Grant Hotel and the Pioneer Opera House in American Fork, Utah. The tall redhead early manifested oratorical abilities and considered a career in the theater but instead turned to teaching. After receiving her education at Westminister College and University of California at Berkeley, Reva married Harold G. Cutler in 1920. The marriage lasted only one year. She continued to teach high school in Delta and then Ogden until 1927 when she entered the University of Utah law school. She married classmate Joseph P. Bosone in 1929. The couple had a daughter in 1930 and opened their law offices the next year in Helper, Utah. They were divorced in 1939.

Bosone lost her first case defending, but she gained recognition when she successfully defended two young men in a well-publicized case of attempted rape. The resulting notoriety helped her secure a seat in the Utah House of Representatives in the Democratic sweep of 1932. The Bosones moved their law firm to Salt Lake City and Reva became a member of the "progressive bloc" of state legislators who sponsored New Deal reform legislation including a minimum wage and hour law for women and children.