Westville is a borough in Gloucester County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 4,288, reflecting a decline of 212 from the 4,500 counted in t…Westville is a borough in Gloucester County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 4,288, reflecting a decline of 212 from the 4,500 counted in the 2000 Census, which had in turn declined by 73 from the 4,573 counted in the 1990 Census. The Borough of Westville is known as "The Gateway to South Jersey!"