Resident Population in Butler County, MO was 41.94800 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Butler County, MO reached a record high of 43.00100 in January of 2012 and a record low of 33.52900 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Butler County, MO - last updated from the United States Federal Reserve on May of 2024.