Alpha is a borough in Warren County, New Jersey. Its population at the 2010 census was 2,369. The borough was incorporated as a borough by an Act of the New Jersey Legislature in 1911. The borough has a total area of 1.7 square miles, of which 1.7 square miles is land and 0.04 square miles (2.30%) is water.
The economy is based on local businesses, professional services, sales and service, and production, construction and transport of materials.