$191 Cheap United flights Seattle (SEA) to Rapid City (RAP)

Set the "Price (lowest to highest)" filter on Expedia to look for cheap United Airlines round-trip flights from $274 from SEA to RAP. Affordable one-way options from $191 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.

For cheap United Airlines fares from Seattle - Tacoma Intl. Airport (SEA) to Rapid City Regional Airport (RAP), start searching one to three months before your planned departure. Reserving 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 impact how much 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.

Filter your results by "Early Morning" and "Morning" to find the earliest departures from SEA to RAP. Jetting off early means you're 20% 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.

Depart from SEA to RAP with United Airlines and you can look forward to a range of perks including a rewarding loyalty program. When booking through Expedia as a United Mileage Plus and One Key™ member, you can 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.