Resident Population in Union County, NM was 3.96400 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Union County, NM reached a record high of 5.21900 in January of 1982 and a record low of 3.70700 in January of 2006. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Union County, NM - last updated from the United States Federal Reserve on May of 2024.