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Amazing United SEA to STL Flight Deals

The cheapest flights to Lambert-St. Louis Intl. found within the past 7 days were $158 round trip and $79 one way. Prices and availability subject to change. Additional terms may apply.


FAQs about United Airlines Flights from SEA to STL

What terminal is United Airlines at Sea-Tac Airport?

If you're traveling with United Airlines from Seattle, WA Airport (SEA-Seattle - Tacoma Intl.) to St. Louis, MO Airport (STL-Lambert-St. Louis Intl.), you should be able to find out the terminal information when you get your boarding pass. If not, consult your airline.

Are there United Airlines non-stop flights from SEA to STL?

As you can't fly nonstop from Seattle, WA Airport (SEA-Seattle - Tacoma Intl.) to St. Louis, MO Airport (STL-Lambert-St. Louis Intl.) with United Airlines, make the most of your stopover. Grab a couple of refreshments at an airport bar, or wander around the terminal and enjoy a little retail therapy.

How long is an United Airlines flight from SEA to STL?

Bring that novel you've been eager to read. A flight from Seattle, WA Airport (SEA-Seattle - Tacoma Intl.) to St. Louis, MO Airport (STL-Lambert-St. Louis Intl.) with United Airlines will take on average 5 hours and 55 minutes. You'll have ample time to get swept up in the storyline.

How many direct and indirect flights does United Airlines fly from SEA to STL?

When flying from SEA to STL, you'll find there are at least 3 United Airlines daily flights to select from.

Flying Tips & Tricks How do I find my flight number?
  • After you lock in your flight, an itinerary should be delivered to your inbox. You'll find the flight number (a mix of numbers and letters) in this document.
How early can you check bags for a flight?
  • There's no need to wait around at home if you're packed and ready to head off on your big adventure. International flights begin their check-in process approximately three hours before departure. Meeting relatives or friends at the airport? Make sure they know that baggage drop closes an hour before takeoff. If you're taking a domestic flight, you should get to the terminal at least one to two hours before departure. Check-in closes 45 minutes before the plane leaves.

*Price based on the lowest price found within past 24 hours and based upon one night stay for two adults over the next thirty days. Prices and availability subject to change. Additional terms may apply.