$131 Cheap United flights Boston (BOS) to Sioux Falls (FSD)

Set the "Price (lowest to highest)" filter on Expedia to look for cheap United Airlines round-trip flights from $209 from BOS to FSD. Affordable one-way fares from $131 are also on offer.**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 Logan Intl. Airport (BOS) to Sioux Falls Regional Airport (FSD) one to three months ahead of your departure day. 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. No matter the fare class and journey, the ideal day 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.

Sort your results by "Morning" and "Early Morning" to browse the earliest flights from BOS to FSD. Heading off early 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.

A rewarding loyalty program and the ability to collect points through United Mileage Plus are the start of the reasons to jet off from BOS to FSD with United Airlines. Plus, when you join our One Key™ program, you can earn OneKeyCash™* alongside any airline loyalty program earnings. It's yours to use wherever your next trip takes you.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.