From the VMRC web page.
Freshwater/Saltwater License Lines on Tidal Rivers
Persons fishing upstream of the designated lines on the following waters must have a valid freshwater fishing license while those fishing below the lines must have a valid saltwater fishing license:
…..Potomac River: Route 301 Bridge
…..Rappahannock River: Route 360 Bridge
…..Piankatank River/Dragon Run: The 1st set of power lines immediately upriver of Anderson Point
…..York River System (including the Mattaponi and Pamunkey Rivers): Route 33 Bridges
…..James River: A line connecting Hog Point and the downstream point of the mouth of College Creek
Below these designated lines a freshwater or saltwater license will be valid on any tidal portion of any tributary entering the above mainstem waters.
The following waters are entirely freshwater and require a freshwater fishing license throughout: Meherrin River; Nottoway River; Blackwater River (Chowan drainage); Back Bay, Northwest River, and North Landing River and Intercoastal Waterway upstream to Great Bridge Locks; and Dismal Swamp Canal below (or South) of Deep Creek Locks.
And other places that a VA saltwater license works.
Chesapeake Bay and Seaside - Anglers with saltwater licenses from either Virginia or Maryland may fish in any portion of the Chesapeake Bay, or any of the saltwater reaches of its tributary rivers, as well as seaside bays and creeks and the Atlantic Ocean where a Virginia saltwater license is required. Virginia licenses honored include: 1) individual annual licenses; 2) individual temporary licenses; 3) private boat licenses covering all persons fishing on the boat; 4) annual licenses for charter boats, headboats, and partyboats; and 5) annual licenses for rental boats.
Note: MD licensees may fish in VA tidal waters as described above without additional license, but must register in the new VA Fisherman Identification Program (FIP) beginning January 1, 2011. Click on following link for more information,
www.mrc.virginia.gov/FIP.
Potomac River - Anglers with saltwater licenses from either Virginia or the Potomac River Fisheries Commission may fish in any portion of the mainstem of the Potomac River to the lower border of D.C.. Virginia licenses honored include: 1) individual annual licenses; 2) individual temporary licenses; 3) private boat licenses covering all persons fishing on the boat; 4) annual licenses for charter boats, headboats, and partyboats; and 5) annual licenses for rental boats.
Note: PRFC licensees may fish in VA tidal water as described above without additional license and do not have to register in the new VA Fisherman Identification Program (FIP). Click on following link for more information,
www.mrc.virginia.gov/FIP.