Resident Population in Passaic County, NJ was 526.59700 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Passaic County, NJ reached a record high of 526.59700 in January of 2024 and a record low of 447.58500 in January of 1980. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Passaic County, NJ - last updated from the United States Federal Reserve on April of 2026.