$139 Cheap United flights Boston (BOS) to St. Louis (STL)

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$139 Cheap United flights Boston (BOS) to St. Louis (STL)

Prices were available within the past 7 days and start at $139 for one-way flights and $209 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

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Flights from Boston (BOS) to St. Louis (STL)
Origin airport
Logan Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, Spirit Airlines, Sun Country Airlines, United
Popular airline
American Airlines
Distance
1043 mi

Frequently asked questions

How much is a United Airlines flight from Logan Intl. Airport (BOS) to Lambert-St. Louis Intl. Airport (STL)?
Finding cheap one-way United Airlines flights from BOS to STL from $139 on Expedia couldn't be simpler --- just filter by "Price (lowest to highest)." Alternatively, check out our budget-friendly round-trip fares from $209 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.
What is the cheapest month to fly from BOS to STL with United Airlines?
January is one of the cheapest months to jet away to St. Louis with United Airlines. You could also find excellent prices on return and one-way tickets in February.
What is the cheapest time to book flights from Logan Intl. Airport (BOS) to Lambert-St. Louis Intl. Airport (STL) with United Airlines?
Start searching one to three months ahead of your departure date to get cheap fares on United Airlines flights from Logan Intl. Airport (BOS) to Lambert-St. Louis Intl. Airport (STL). 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 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 trips.*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.
Does United Airlines fly nonstop from Logan Intl. Airport (BOS) to Lambert-St. Louis Intl. Airport (STL)?
To find out if there's a direct route from BOS to STL with United Airlines or another airline, select the "Nonstop" filter when searching for tickets.
What is the earliest United Airlines flight from BOS to STL?
Filter your results by "Morning" and "Early Morning" to browse the earliest departures from BOS to STL. Heading off early means flight 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.
What airports does United Airlines fly into in St. Louis?
Lambert-St. Louis Intl. Airport (STL) is the main St. Louis gateway for United Airlines flights from Logan Intl. Airport (BOS).
Why fly with United Airlines from BOS to STL?
Depart from BOS to STL with United Airlines and you'll enjoy a range of perks 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 use on select future travel purchases.*OneKeyCash™ disclaimer - OneKeyCash™ is not redeemable for cash and can only be used on Expedia, Hotels.com and Vrbo.
Can I change or cancel my United Airlines flight from Logan Intl. Airport (BOS) to Lambert-St. Louis Intl. Airport (STL)?
Changes are typically free within 24 hours of making your booking, but your airline may add a charge after that time. For more information about modifying your reservation, head to your "Trips," select your flight and click on "Manage Booking." If you'd like the freedom to change your itinerary without additional charges, check the "Changes included" or "No cancel fee" filter when organizing your next adventure.

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*Available to One Key members.