Lawnside is a borough in Camden County, in the U.S. state of New Jersey. Lawnside was developed in 1840 and incorporated in 1926 as the first independent, self-governing Black municipality north of the Mason–Dixon line. The United Parcel Service has a large depot in the borough. As of the 2020 United States census, the borough's population was 2,955, an increase of 10 from the 2010 census count of 2,945, which in turn reflected an increase of 253 from the 2,692 counted in the 2000 census.