Newtonville is an unincorporated community and census-designated place (CDP) in Buena Vista Township in Atlantic County, in the U.S. state of New Jersey. Newtonville is located on a Conrail line 4.7 miles (7.6 km) east-northeast of Buena. Newtonville has a post office with ZIP Code 08346. Newtonville, NJ, is a historically African American town that developed as a significant settlement for Black families migrating from urban areas such as Philadelphia. These migrations were often motivated by the search for better living conditions, opportunities for self-sufficiency, and a chance to escape the restrictive racial environments of larger cities during the early to mid-20th century.

This settlement played a key role in fostering a strong African American community within Buena Vista Township. Newtonville, NJ, is located within Buena Vista Township, and holds historical significance for its contributions to the community's cultural, social, and economic development. Established as part of a rural region in southern New Jersey, it is known for its connection to the African American heritage in the area. In 1998, the Dr. Martin Luther King Community Center was opened in Newtonville, followed in 2003 by the African American Heritage Museum of Southern New Jersey at the same site. These institutions serve as cultural landmarks and focus on community engagement and education about African American history and contributions to the region.

As of the 2020 United States census, the population was 742.

Historical population

Census	Pop.	Note	%±
2020	742		—
U.S. Decennial Census 2020