Welcome to SIXT car rental Dulles Airport. When you need a car rental at IAD, SIXT has premium cars to suit your needs. SIXT has fantastic deals whether you need car rental at Dulles Airport for a daily, weekly or a long-term rental. If you want a cheap deal on a rental car, choose one of our sedans and head to famous landmarks in the Washington, D.C. area such as the United States Capitol or the Smithsonian Museums. If you have a larger group, put everyone in one of our minivans and go on an outdoor adventure at Rock Creek Park. Our branch at IAD is easily reached via shuttle bus.