Loudoun County, Virginia

county in Virginia, United States

Loudoun County (/ˈldən/ LOWD-ən) is a county in the U.S. state of Virginia. It is part of the Washington Metropolitan Area. The 2020 U.S. Census said 420,959 people live there.[3] Its county seat is Leesburg.[4][5]

Loudoun County
Loudoun County Courthouse and a World War II monument (right) in Leesburg, February 2021
Loudoun County Courthouse and a World War II monument (right) in Leesburg, February 2021
Flag of Loudoun County
Official seal of Loudoun County
"I Byde My Time"[1]
Map of Virginia highlighting Loudoun County
Location within the U.S. state of Virginia
Map of the United States highlighting Virginia
Virginia's location within the U.S.
Coordinates: 39°05′N 77°38′W / 39.09°N 77.64°W / 39.09; -77.64
Country United States
State Virginia
Named forJohn Campbell, 4th Earl of Loudoun[2]
Largest townLeesburg
 • Total521.33 sq mi (1,350.2 km2)
 • Land515.74 sq mi (1,335.8 km2)
 • Water5.6 sq mi (15 km2)  1.1%
 • Total420,959
 • Density810/sq mi (310/km2)
Time zoneUTC−5 (Eastern)
 • Summer (DST)UTC−4 (EDT)
Congressional district10th

The number of people grew 84 percent from 2000 to 2010, and 34 percent from 2010 to 2020.

As of 2007, Loudoun County has the highest median household income of any county in the United States ($107,207). This is higher than nearby Fairfax County, Virginia ($105,241).[6]


  1. Rosalind S. Helderman, Proud Past, Bright Future Rub Elbows in Today's Loudoun, Washington Post (April 21, 2005), page LZ03.
  2. "About Loudoun - History". Loudoun County. Retrieved January 3, 2013.
  3. "QuickFacts: Accomack County, Virginia". United States Census Bureau. Retrieved January 25, 2024.
  4. National Association of Counties. "NACo County Explorer". Retrieved January 25, 2024.
  5. Loudoun Times-Mirror, "Leesburg says county should stay", September 12, 2007, Page A1
  6. Income, Earnings, and Poverty Data From the 2007 American Community Survey