There are 12 US Post Offices in Bonner County serving a total of 36,150 residents equating to 3,013 residents per post office. It's estimated that approximately 57,699 packages are handled across the 12 county post offices annually. Bonner County is a county located in the northern part of the U.S. state of Idaho. As of the 2010 census, the population was 40,877. The county seat and largest city is Sandpoint. Partitioned from Kootenai County and established in 1907, it was named for Edwin L. Bonner, a ferry operator. Bonner County comprises the Sandpoint, ID Micropolitan Statistical Area."