Callaway County is a county located in the U.S. state of Missouri. As of the 2020 United States Census, the county's population was 44,283. Its county seat is Fulton. With a border formed by the Missouri River, the county was organized November 25, 1820, and named for Captain James Callaway, grandson of Daniel Boone. The county has been historically referred to as "The Kingdom of Callaway" after an incident in which some residents confronted Union troops during the U.S. Civil War.

The Jefferson City metropolitan statistical area, as defined by the United States Census Bureau, is an area consisting of four counties – Cole, Callaway, Moniteau, and Osage – in central Missouri anchored by the city of Jefferson City. As of the 2020 census, the MSA had a population of 150,316. The Jefferson City MSA consists of four counties, and borders the Columbia metropolitan area to the north.