| Name | Reporting mark | System[nb 1] | From | To | Successor | Notes |
| Alexandria and Fredericksburg Railway | | RF&P | 1872 | 1890 | Baltimore and Potomac Railroad | |
| Alexandria and Washington Railroad | | RF&P | 1854 | 1872 | Alexandria and Fredericksburg Railway | |
| Baltimore and Ohio Railroad | B&O, BO | B&O | 1831 | 1987 | Chesapeake and Ohio Railway | |
| Baltimore and Potomac Railroad | | PRR | 1867 | 1902 | Philadelphia, Baltimore and Washington Railroad | |
| Chesapeake Beach Railway | | | 1896 | 1935 | East Washington Railway | |
| Chesapeake and Ohio Railway | C&O, CO | C&O | 1891 | 1987 | CSX Transportation | |
| Consolidated Rail Corporation | CR | | 1976 | 1999 | CSX Transportation/Norfolk Southern Railway | |
| East Washington Railway | | | 1935 | 1976 | N/A | |
| Georgetown Barge, Dock, Elevator and Railway Company | | B&O | 1888 | 1972 | Baltimore and Ohio Railroad | |
| Orange, Alexandria and Manassas Railroad | | SOU | 1872 | 1872 | Virginia and North Carolina Railroad | |
| Penn Central Transportation Company | PC | | 1968 | 1976 | Consolidated Rail Corporation | |
| Pennsylvania Railroad | PRR | PRR | 1918 | 1968 | Penn Central Transportation Company | |
| Philadelphia, Baltimore and Washington Railroad | | PRR | 1902 | 1976 | Consolidated Rail Corporation | |
| Philadelphia, Wilmington and Baltimore Railroad | | PRR | 1891 | 1902 | Philadelphia, Baltimore and Washington Railroad | |
| Richmond and Danville Railroad | | SOU | 1886 | 1894 | Southern Railway | |
| Richmond, Fredericksburg and Potomac Railroad | RF&P, RFP | RF&P | 1920 | 1991 | Richmond, Fredericksburg and Potomac Railway | |
| Richmond, Fredericksburg and Potomac Railway | RFP | | 1991 | | | Still exists as a subsidiary of CSX Transportation |
| Southern Railway | SOU | SOU | 1894 | 1990 | Norfolk Southern Railway | |
| Southern Maryland Railroad | | | 1882 | 1886 | Washington and Potomac Railroad | |
| Virginia Midland Railway | | SOU | 1880 | 1886 | Richmond and Danville Railroad | |
| Virginia and North Carolina Railroad | | SOU | 1872 | 1873 | Washington City, Virginia Midland and Great Southern Railway | |
| Washington, Alexandria and Georgetown Railroad | | RF&P | 1862 | 1868 | Alexandria and Washington Railroad | |
| Washington City and Point Lookout Railroad | | B&O | 1873 | 1874 | Baltimore and Ohio Railroad | |
| Washington City, Virginia Midland and Great Southern Railway | | SOU | 1873 | 1880 | Virginia Midland Railway | |
| Washington and Potomac Railroad | | | 1886 | 1900 | Washington, Potomac and Chesapeake Railroad | |
| Washington, Potomac and Chesapeake Railroad | | | 1901 | 1910 | Washington, Potomac and Chesapeake Railway | |
| Washington, Potomac and Chesapeake Railway | | | 1910 | 1918 | Chesapeake Beach Railway | |
| Washington Southern Railway | WSN | RF&P | 1901 | 1920 | Richmond, Fredericksburg and Potomac Railroad | |
| Washington Terminal Company | WATC | B&O/ PRR | 1901 | | | Still exists as a subsidiary of the National Railroad Passenger Corporation (Amtrak) |
| Washington and Western Maryland Railroad | | B&O | 1889 | 1985 | N/A | |