South Fairfax Chamber of Commerce P. O. Box 68, Lorton, VA22199 The South Fairfax Chamber of Commerce is a community organization for businesses, nonprofit organizations and…More individuals with interests in the southern part of Fairfax County. The organization works to develop the economy in the area and offer member businesses a wide range of benefits and services. Some benefits of membership include online directory listings, free web pages and access to organization events and workshops. Check the main site for a full list of businesses in the directory and for details on how to join.