Franconia is a census-designated place (CDP) in Fairfax County, Virginia, United States. The population was 18,245 at the 2010 census, down from 31,907 in 2000 due to the splitting off of part of it to form Kingstowne CDP.
Located just southwest of Alexandria, Franconia has existed as a community since the 1870s, when a station by that name opened on the RF&P Railroad; however, like most of the surrounding area, it only began to develop into its present, suburban form in the 1950s. The CDP extends further south to the border of Fort Belvoir, encompassing most of Kingstowne and other neighborhoods such as Hayfield, Manchester Lakes and Windsor Park. Street addresses have Alexandria ZIP codes 22310 and 22315.