Northern Neck National Heritage Area Act This bill establishes the Northern Neck National Heritage Area in Virginia. The bill includes in the heritage area land between the Potomac River and Rappahannock River of the eastern coastal region of Virginia, including King George, Lancaster, Northumberland, Richmond, and Westmoreland Counties. The bill designates the Northern Neck Tourism Commission, a working committee of the Northern Neck Planning District Commission, as the local coordinating entity for the heritage area. The Northern Neck Tourism Commission shall submit a proposed management plan for the heritage area to the Department of the Interior for approval.