Hello! If you're taking a flight at Washington Dulles, the United Airlines IAD Terminal is a good option. United is primarily based in Terminal C and D, which provides a convenient experience with lots of eateries and retail shops. The lounges, particularly the Polaris Lounge, are great for premium flyers. Although the airport's train network assists with connections, some gates will still need a shuttle ride. Overall, United Airlines provides comfort and efficiency, although it tends to get congested during peak hours. Wonderful hub for international and domestic flights!