$119 Cheap American Airlines flights Harlingen (HRL) to Washington (IAD)

Scoring cheap one-way American Airlines flights from HRL to IAD from $119 on Expedia is simple — just filter by "Price (lowest to highest)." Alternatively, check out our affordable return fares from $260 for your next adventure.**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.

To find cheap American Airlines fares from Valley Intl. Airport (HRL) to Washington Dulles Intl. Airport (IAD), start searching one to three months before your planned departure. Securing domestic flights 34 to 86 days in advance could save you 25% compared to booking just 6 to 12 days ahead. The day you book can also influence what you pay. Sunday is generally the cheapest, while Monday is often the most expensive for domestic flights. You can save 6% on average by booking your flight on a Sunday.**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.

Sort your results by "Morning" and "Early Morning" to find the earliest flights from HRL to IAD. Setting off early means flight cancellations are less likely.**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.