Mount Arlington's
Daily Encourager

Mount Arlington is a borough in western Morris County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 5,909, an increase of 859 (+17.0%) from the 2010 census count of 5,050, which in turn reflected an increase of 387 (+8.3%) from the 4,663 counted in the 2000 census.