There are 6 US Post Offices in Benewah County serving a total of 9,764 residents equating to 1,627 residents per post office. It's estimated that approximately 15,584 packages are handled across the 6 county post offices annually. Benewah County is a county located in the U.S. state of Idaho. As of the 2010 census the county had a population of 9,285. The county seat and largest city is St. Maries. The county was established on January 23, 1915 from sections of Kootenai County and was named for a chief of the Coeur d'Alene Tribe. The federally recognized Coeur d'Alene Tribe is based on the Coeur d'Alene Reservation in this county."