$115 Cheap United flights Baltimore (BWI) to Harlingen (HRL)

Scoring cheap one-way United Airlines flights from BWI to HRL from $115 on Expedia is easy — just filter by "Price (lowest to highest)." Or check out our affordable round-trip fares from $243 for your next break.**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 cheap United Airlines flights from Baltimore Washington Intl. Thurgood Marshall Airport (BWI) to Valley Intl. Airport (HRL) one to three months ahead of your departure date. Travelers who book domestic flights 34 to 86 days in advance can save 25% compared to those who book just 6 to 12 days ahead. Regardless of fare type and itinerary, the best day of the week to book a domestic flight is generally Sunday and the most expensive day is typically Monday. Passengers who book on a Sunday can save 6% on average compared to those who book on a Monday.**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 departure from BWI to HRL with United Airlines, sort your results by "Early Morning" and "Morning." Booking an early flight usually 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.

Travel from BWI to HRL with United Airlines and you can look forward to a range of benefits starting with a rewarding loyalty program. When you book through Expedia as a United Mileage Plus and One Key™ member, you may also earn OneKeyCash™* to spend on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.