How long would that take from Reagan to Dulles by taxi, and how much it would cost?
For a cheaper alternative than a direct cab, take the 5A bus (45 minutes - $7.50) till Rosslyn and then a cab (5 minutes - $10) or metro blue line (10 minutes - $3) to Reagan airport. Be sure to check out the 5a schedule before you choose this option
Lyft or Uber is your best bet.
You have to have your Passport with you as always, have your document ready, plus your boarding pass, airline tickets, than take the public transportation to get there. In buses, you must take Dulles Airport Main Terminal to N Moore St & Rosslyn or the Metro of the Blue Line for Ronald Reagan and Silver for Dulles International. In Taxi Cab service, it usually cost from $95- $120 dollars per person in the one way transfer. In Uber, it cost from $38-$43 per travel in one way connection.
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