$105 Cheap United flights Harlingen (HRL) to Chicago (ORD)

Make use of the "Price (lowest to highest)" filter on Expedia to find cheap United Airlines return flights from $251 from HRL to ORD. Affordable one-way tickets from $105 are available too.**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.

Start searching one to three months ahead of your travel date to find cheap fares on United Airlines flights from Valley Intl. Airport (HRL) to O'Hare Intl. Airport (ORD). You can save 25% by booking your domestic flight 34 to 86 days in advance compared to last-minute reservations made 6 to 12 days out. You could also reduce costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Get your timing right, and you can enjoy significant savings on domestic journeys.*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 HRL to ORD with United Airlines, filter your search by "Morning" and "Early Morning." Booking an early flight generally means 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.

Travel from HRL to ORD with United Airlines and you'll enjoy a host of benefits starting with a rewarding loyalty program. When booking 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.