$103 Cheap flight deals from Boston (BOS) to Union (STL)
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This Weekend's Flight Deals from Boston to Union
This weekend's flight prices found within the past 7 days, for the period specified. Prices and availability are subject to change. Additional terms apply.
Airfares from $103 One Way, $205 Round Trip from Boston to Union
Prices starting at $205 for return flights and $103 for one-way flights to Union were the cheapest prices found within the past 7 days, for the period specified. Prices and availability are subject to change. Additional terms apply.
Union economy flight packages
Ameristar Casino Resort and Spa
Apr 28 - May 2
Boston (BOS) to St. Louis (STL)
Reviewed on Dec 2, 2025
Hampton Inn & Suites Clayton/St. Louis-Galleria Area
Apr 28 - May 2
Boston (BOS) to St. Louis (STL)
Reviewed on Apr 20, 2022
More About Flying To Union from Boston
Route Information for Flights from Boston to Union
Origin Airport IATA Code | BOS |
|---|---|
Destination Airport IATA Code | STL |
Distance | |
Direct Flight Airlines | |
Earliest Flight Arrival | |
Latest Flight Arrival |
Boston to Union
Whether you want to book cheap flights from Boston to Union or are looking for the perfect package holiday, Orbitz is your one-stop source. Taking the stress and expense out of travel, Orbitz helps you find the best fares for Boston to Union flights.
Make the Most of Your Vacation
Not only does Orbitz have cheap deals for Boston to Union flights, we can also help you plan your vacation in advance. Why wait in lengthy lines for tickets to shows, amusement parks, and other attractions when you could be making the most of your holiday? Add activities to your flight booking for fewer hassles once you arrive in Union.
Planning on the Go
Book your flights from Boston to Union wherever you are with the Orbitz app for Android and iPhone. Or simply use m.orbitz.com on your mobile browser to search and book the Boston to Union flights that you want. And if you’re running late, you check your flight status and baggage claim information on your mobile device too too.
Craft Your Perfect Vacation
Orbitz takes the stress out of vacation planning with great deals on flights from Boston to Union, hotels, car rentals, cruises, and more. Mix and match results for your perfect trip, or book a complete vacation package.
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Flights from Boston
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Union Airports
Fare, taxes & fees: Fares include all taxes and fees, except baggage fees. Rates shown reflect fares found by other Orbitz users over the past 7 days. Due to rapidly changing airline prices & seat availability, these fares may no longer be available.
Refunds/changes/cancellations: Itinerary changes, if permitted for the fare, will have a $30 service fee charged by Orbitz. Additional airline charges may apply.
Other conditions: Schedules, fares and rules are subject to change without notice. Seats are limited and may not be available on all flights/dates or in all markets. Lower fares may be available. Fares will not be honored retroactively or in exchange for any wholly/partially unused ticket. Tickets are non-transferable and non-refundable. Fare rules are provided for the selected itinerary before booking.