Resident Population in Essex County, NJ was 851.11700 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Essex County, NJ reached a record high of 943.40000 in January of 1971 and a record low of 765.69500 in January of 2008. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Essex County, NJ - last updated from the United States Federal Reserve on May of 2024.