Resident Population in Knox County, ME was 40.97700 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Knox County, ME reached a record high of 41.16400 in January of 2022 and a record low of 29.01300 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Knox County, ME - last updated from the United States Federal Reserve on May of 2024.