Resident Population in Effingham County, IL was 34.33100 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Effingham County, IL reached a record high of 34.69500 in January of 2020 and a record low of 24.60800 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Effingham County, IL - last updated from the United States Federal Reserve on June of 2024.