Resident Population in Champaign County, IL was 205.64400 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Champaign County, IL reached a record high of 210.63000 in January of 2017 and a record low of 163.28100 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Champaign County, IL - last updated from the United States Federal Reserve on May of 2024.