$176 Cheap United flights Chicago (ORD) to Rapid City (RAP)

You can find affordable round-trip United Airlines flights from $209 from ORD to RAP by organizing your results from "Price (lowest to highest)" on Expedia. Or search for options from $176 for a one-way trip.**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.

Begin your search one to three months ahead of your departure date to find cheap fares on United Airlines flights from O'Hare Intl. Airport (ORD) to Rapid City Regional Airport (RAP). You can save 25% by booking your domestic flight 34 to 86 days in advance versus last-minute reservations made 6 to 12 days out. You could also cut costs by buying your fare on a Sunday, as it's 6% cheaper on average than a Monday, the most expensive day to book.* Nail your timing, 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 ORD to RAP with United Airlines, sort your results by "Early Morning" and "Morning." Booking an early flight usually 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.

A rewarding loyalty program and the opportunity to collect points through United Mileage Plus are the start of the reasons to fly from ORD to RAP with United Airlines. Plus, by joining Expedia's free One Key™ program, you can receive OneKeyCash™* in addition to 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.