There are 13 US Post Offices in Caddo County serving a total of 32,029 residents equating to 2,464 residents per post office. It's estimated that approximately 51,122 packages are handled across the 13 county post offices annually. Caddo County is a county located in the U.S. state of Oklahoma. As of the 2010 census, the population was 29,600. Its county seat is Anadarko. Created in 1901 as part of Oklahoma Territory, the county is named for the Caddo tribe who were settled here on a reservation in the 1870s. Caddo County is immediately west of the seven-county Greater Oklahoma City metro area, and although is not officially in the metro area, it has many economic ties in this region.