Born 4 October 1877, in Bountiful, Utah, fourth son of Sarah Lucretia Tolman and Joseph Thomas Mabey, both of whom were Mormons. Brother of Thomas, Judson Adoniram, William Albert, Joseph L., George Edward, Clarence, David, Sarah Lucretia Mabey Hepworth, Orson Henry, Alice Ethel Mabey Fishler, and Esther Mabey Lee. Married to Afton Rampton on 20 December 1905. Father of Rentell Noel, Charles Pace, Robert Burns, and Edward Milo. Attended the University of Utah and graduated with a normal (teaching) certificate in 1896. Spent most of the next decade as a school teacher and administrator, but also served a tour of duty with the Utah National Guard in the Philippines during the Spanish-American War and a three-year proselytizing mission for the Church of Jesus Christ of Latter-day Saints (Mormon) in Germany. Prior to his election as governor, he served as justice of the peace and as city councilman and mayor of Bountiful, Utah. He was also elected to two terms (1912-1914 and 1914-1916) in the state house of representatives. He was commissioned a captain in the artillery, 3 July 1917, and served on active duty, mostly at Fort Sill, Oklahoma, until 13 December 1918. Receiving the Republican nomination for governor in 1920, he defeated Democratic opponent T.N. Taylor by a record majority of 86,618 to 54,913 votes.

As Utah's fifth governor, Charles R. Mabey proved to be particularly friendly to the state's public education system. Many new schools were built and standards for teacher certification were upgraded. He was also aggressive in promoting new highway construction in the state, drawing on federal grants in aid and initiating a sales tax on gasoline. Upon his recommendation the legislature approved Utah's entry into the Colorado River Compact. He directed an extensive reorganization of the state administrative system which cut the total cost of state services considerably. It also had the effect of eliminating a number of patronage positions. From the outset Governor Mabey had refused to cooperate with party spoils men who at that time were highly influential in Utah's Republican party. Additionally, heavy outlays for education and highways seemed to violate the austerity pledges made during his campaign. Depressed economic conditions in the state added to the growing discontent, and in his bid for reelection in 1924 Mabey (72,127 votes) was soundly defeated by Democrat George Dern (81,308 votes) in a state election where Republicans won every other major race.

After leaving the governor's office in 1925 Charles Mabey remained active in business, civic, and church affairs. He presided over the Bountiful State Bank, held state and national positions in the American Legion, and served on the general board of an LDS church auxiliary. He died 26 April 1959, at age 81.