Sandpoint is the largest city in, and the county seat of, Bonner County, Idaho, United States. Its population was 9,777 as of the 2022 census…Sandpoint is the largest city in, and the county seat of, Bonner County, Idaho, United States. Its population was 9,777 as of the 2022 census. Sandpoint's major economic contributors include forest products, light manufacturing, tourism, recreation and government services. As the largest service center in the two northern Idaho counties, as well as northwestern Montana, it has an active retail sector.