There are 11 US Post Offices in Kootenai County serving a total of 140,127 residents equating to 12,739 residents per post office. It's estimated that approximately 223,658 packages are handled across the 11 county post offices annually. Kootenai County (/\u02c8ku\u02d0tni\u02d0/ KOOT-nee) is a county located in the U.S. state of Idaho. As of the 2010 census, the population was 138,494, making it the third-most populous county in Idaho. The county seat and largest city is Coeur d'Alene. The county was established in 1864 and named after the Kootenai tribe. Kootenai County comprises the Coeur d'Alene, ID Metropolitan Statistical Area, which is included in the Spokane-Spokane Valley-Coeur d'Alene, WA-ID Combined Statistical Area."