The Potomac District is a high school conference in the VHSL that is made up of mostly schools from Loudoun County that have a high enrollment capacity.
The original Potomac District was founded in 1965 when the Northern Region expanded from two to three districts along with the Alexandria District and the Northern District. The original charter members of the district were Langley, Marshall, McLean, J.E.B. Stuart, Wakefield, Washington-Lee and Yorktown. The district lasted until 1972 due to low membership but was revived in 1975 and then disbanded again in 1994 when the Northern Region realigned the districts.
In 2015, the current Potomac District was revived to alleviate crowding within the Dulles District and for schools in Loudoun County with a higher enrollment. With the opening of Tuscarora in 2010 and the increasing enrollment by Briar Woods, Broad Run, Stone Bridge and Potomac Falls, led to the district's creation. The result made the Dulles District only have schools in Class 4A or below.