There are 10 US Post Offices in Colorado County serving a total of 20,147 residents equating to 2,015 residents per post office. It's estimated that approximately 32,157 packages are handled across the 10 county post offices annually. Colorado County is a county located in the U.S. state of Texas. As of the 2010 census, its population was 20,874. Its county seat is Columbus. It is named for the Colorado River of Texas. The county was founded in 1836 and organized the next year."