Resident Population in Benton County, IA was 25.79600 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Benton County, IA reached a record high of 26.72000 in January of 2009 and a record low of 22.21400 in January of 1987. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Benton County, IA - last updated from the United States Federal Reserve on May of 2024.