Taxicabs are free to operate in adjoining jurisdictions and this is vital, considering that there are two states plus the District and several counties and cities in a small area. Maryland taxis are metered with rates set by the jurisdiction (about $4 to board and plus 50¢ for each quarter mile in Montgomery County and a $3 flag fare with 25¢ for every seventh of a mile in Prince George's County). Taxis are usually waiting near the busier Metrorail stations like Bethesda, Silver Spring, and Greenbelt, and the bigger hotels.
Taxis at the Virginia airports are very tightly regulated. Washington Flyer cabs serve Dulles International Airport exclusively from the airport but any taxi can deliver there. A starter outside the arrivals area at Reagan National loads taxicabs from a regulated line of incoming taxis and will provide a fare sheet if desired. An airport fee of $2.50 is added to your fare to pay for this service. Some taxi drivers accept credit cards, but ask first.