Haddonfield is a borough located in Camden County, in the U.S. state of New Jersey. As of the 2020 United States census, the borough's population was 12,550, an increase of 957 (+8.3%) from the 2010 census count of 11,593, which in turn reflected a decline of 66 (−0.6%) from the 11,659 counted in the 2000 census.