$1,598 Cheap United flights Guam (GUM) to Washington (IAD)

Apply the "Price (lowest to highest)" filter on Expedia to find cheap United Airlines return flights from $1,577 from GUM to IAD. Affordable one-way tickets from $1,598 are also available.**These prices were available on Expedia within the past 7 days, for flights departing within the next year. Prices and availability are subject to change. Additional terms apply.

Search for United Airlines flights from GUM to IAD about one month before you want to go. The cheapest time to reserve an international flight is usually 18 to 29 days ahead of your travel date when you can save 17% versus booking four to five months in advance. Regardless of itinerary or fare class, the best day to book international airfare is usually Sunday. Friday is often the most expensive. Passengers who book on a Sunday can save an average of 17% compared to those who book on a Friday.**Ideal booking window recommendation is based on average round-trip ticket prices for January through November for 2024. Best day of the week to book recommendation is based on average round-trip ticket prices for January through October 2024. All data sourced from ARC's global airline sales database.

To find the earliest departures from GUM to IAD with United Airlines, filter your results by "Early Morning" and "Morning." Booking an early flight generally means you're less likely to experience cancellations.**Most reliable time of the day recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.

A rewarding loyalty program and the ability to collect points through United Mileage Plus are the start of the reasons to travel from GUM to IAD with United Airlines. Plus, when you join Expedia's free One Key™ program, you can receive OneKeyCash™* on top of any airline loyalty program earnings. You can put it toward your future trips.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.