$432 Cheap United flights St. Louis (STL) to Shannon (SNN)

View $432 flight on Mon, Oct 6, 2025Opens in a new window

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$432 Cheap United flights St. Louis (STL) to Shannon (SNN)

Prices were available within the past 7 days and start at $432 for one-way flights and $536 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

United
Mon, Aug 4 - Tue, Aug 19
STL
St. Louis
SNN
Shannon
$536 Roundtrip, found 4 days ago
$536
Roundtrip
found 4 days ago
Select United flight, departing Mon, Aug 4 from St. Louis to Shannon, returning Tue, Aug 19, priced at $536 found 4 days ago
United
Sat, Aug 9 - Tue, Aug 19
STL
St. Louis
SNN
Shannon
$542 Roundtrip, found 16 hours ago
$542
Roundtrip
found 16 hours ago
Select United flight, departing Sat, Aug 9 from St. Louis to Shannon, returning Tue, Aug 19, priced at $542 found 16 hours ago
United
Tue, Oct 7 - Tue, Oct 14
STL
St. Louis
SNN
Shannon
$542 Roundtrip, found 3 days ago
$542
Roundtrip
found 3 days ago
Select United flight, departing Tue, Oct 7 from St. Louis to Shannon, returning Tue, Oct 14, priced at $542 found 3 days ago
United
Tue, Oct 7 - Tue, Oct 14
STL
St. Louis
SNN
Shannon
$547 Roundtrip, found 3 days ago
$547
Roundtrip
found 3 days ago
Select United flight, departing Tue, Oct 7 from St. Louis to Shannon, returning Tue, Oct 14, priced at $547 found 3 days ago
United
Mon, Oct 6 - Tue, Oct 14
STL
St. Louis
SNN
Shannon
$547 Roundtrip, found 3 days ago
$547
Roundtrip
found 3 days ago
Select United flight, departing Mon, Oct 6 from St. Louis to Shannon, returning Tue, Oct 14, priced at $547 found 3 days ago
United
Tue, Sep 9 - Tue, Sep 23
STL
St. Louis
SNN
Shannon
$557 Roundtrip, found 3 days ago
$557
Roundtrip
found 3 days ago
Select United flight, departing Tue, Sep 9 from St. Louis to Shannon, returning Tue, Sep 23, priced at $557 found 3 days ago
Flights from St. Louis (STL) to Shannon (SNN)
Origin airport
Lambert-St. Louis Intl.
Destination airport
Shannon
Airlines serving
Air Canada, American Airlines, British Airways, Delta, Lufthansa, United
Popular airline
American Airlines
Distance
3826 mi

Frequently asked questions

How much is a United Airlines flight from Lambert-St. Louis Intl. Airport (STL) to Shannon Airport (SNN)?
Scoring cheap one-way United Airlines flights from STL to SNN from $432 on Expedia is easy --- just filter by "Price (lowest to highest)." Or check out our budget-friendly round-trip fares from $536 for your next exciting vacation.**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 STL to SNN with United Airlines?
United Airlines flights to Shannon are typically more affordable in the low-season months of January and February. Whether you're searching for a one-way or a return ticket, you could find a better deal then.
What is the cheapest time to book flights from Lambert-St. Louis Intl. Airport (STL) to Shannon Airport (SNN) with United Airlines?
Search for United Airlines flights from STL to SNN about one month before you want to leave. The cheapest time to reserve an international flight is generally 18 to 29 days ahead of your departure date when you can save 17% versus booking four to five months in advance. Regardless of ticket type or itinerary, the best day to book international airfare is usually Sunday. Friday is often the most expensive. Travelers who book on a Sunday can save an average of 17% compared to those who book on a Friday.**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 Lambert-St. Louis Intl. Airport (STL) to Shannon Airport (SNN)?
To figure out if there's a direct trip from STL to SNN with United Airlines or other airlines, use our "Nonstop" filter when browsing for tickets.
What is the earliest United Airlines flight from STL to SNN?
To find the earliest departure from STL to SNN with United Airlines, sort your results by "Morning" and "Early Morning." Choosing an early flight usually 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.
What airports does United Airlines fly into in Shannon?
Hop on a United Airlines flight from Lambert-St. Louis Intl. Airport (STL) to Shannon, and you'll probably arrive at Shannon Airport (SNN). This is the airline's primary hub in this city.
Why fly with United Airlines from STL to SNN?
A rewarding loyalty program and the ability to collect points through United Mileage Plus are the start of the reasons to travel from STL to SNN with United Airlines. Plus, when you sign up to our One Key™ program, you can earn OneKeyCash™* in addition to any airline loyalty program earnings. It's yours to spend on future travel plans.*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 Lambert-St. Louis Intl. Airport (STL) to Shannon Airport (SNN)?
Depending on the ticket type you purchased, a fee will generally apply if you cancel or reschedule your booking more than 24 hours after it has been confirmed. To find flexible fares, select our "No cancel fee" or "Changes included" filter when searching for flights. For more information on modifying or canceling your reservation, go to "Trips," select your flight and click on "Manage Booking."

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