Springfield is a census-designated place (CDP) in Fairfax County, Virginia, United States. The Springfield CDP is recognized by the U.S. Census Bureau with a population of 31,339 as of the 2020 census. Previously, per the 2010 census, the population was 30,484. Homes and businesses in bordering CDPs including North Springfield, West Springfield, and Newington are usually given a Springfield mailing address. The population of the collective areas with Springfield addresses is estimated to exceed 100,000. The CDP is a part of Northern Virginia, the most populous region of the Washington Metropolitan Area.