Cheap flights from Seattle to St. Louis

Round-trip
Economy
Seattle (SEA)
St. Louis (STL)
Depart
Return
Any month
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How to find the cheapest flight from
Seattle (SEA) to St. Louis (STL)

All the information you need to plan the best SEA to STL flight in 2021: compare Seattle to St. Louis flight prices with the expected peak season, weather and rainfall in St. Louis.
SEA - STL
Price
C$ 311 - C$ 508
STL
Temperature
0 - 27 °C
STL
Precipitation
56 - 119 mm

Popular in

December

High demand for flights, 27% potential price rise

Cheapest in

August

Best time to find cheap flights, 16% potential price drop

Average price

C$ 369

Average for round-trip flights in setiembre 2021

Round-trip from

$311

From Seattle/Tacoma Intl to Lambert-St Louis

Flight route prices based on searches on Cheapflights within the last 3 days, monthly prices based on aggregated historical data.
What is the cheapest day to fly round-trip from Seattle to St. Louis?

Users have found that leaving on a Thursday can be a cost-effective option. It’s possible to save up to 60% on your flight compared to booking on days when demand is much higher.

How far in advance should I book a flight from Seattle to St. Louis?

To save on the cost of your flight from Seattle to St. Louis, book at least 28 days before your planned departure. Booking around this time can save you about 69% on the cost of this flight compared to booking a flight leaving this week. We have found prices from C$ 400 if you need a flight within two weeks. For flights within the next 72 hours, you can find tickets from as low as C$ 587.

What is the cheapest month to fly from Seattle to St. Louis?

The best pricing can be found in the month of August. Prices to St. Louis from Seattle average C$ 371. You can even find prices in August for less than C$ 371, as users have found deals to St. Louis from as low as C$ 224. The month of December appears to be one of the more expensive times to travel to St. Louis from Seattle. Flying in the targeted month can save you up to 37%.

When is the cheapest time to fly from Seattle to St. Louis (SEA - STL)?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Seattle to St. Louis as you normally would.

Related info for your journey

Useful info, stats and facts about <span class="emphasized">Seattle</span> to <span class="emphasized">St. Louis</span> flights.

Flight FAQs

From Seattle to St. Louis

What days are direct flights available from Seattle to St. Louis?

Direct flights are available for this route on the following days: Friday, Saturday.

How popular is this Seattle to St. Louis flight route?

Flights from Seattle/Tacoma Intl to Lambert-St Louis have been viewed 13 times in the past calendar month.

How many flights depart from Seattle to St. Louis on average per day?

Per day, 2 flights depart from Seattle to St. Louis on average.
Early Morning (Midnight to 6am) - 50% of flight departures
Morning (6am - Midday) - 50% of flight departures

What are the most reliable airlines from Seattle to St. Louis?

The top 3 most reliable airlines when flying from Seattle to St. Louis are Alaska Airlines (87%), Japan Airlines (84%) and Qatar Airways (84%).

COVID Restrictions

View COVID Travel Restrictions for St. Louis, MO

Do I need a COVID test to fly to St. Louis from Seattle?

Information is based on travel restrictions for travel to Lambert-St Louis within the United States

Most visitors from Seattle/Tacoma Intl need to provide a negative COVID-19 test result and/or quarantine to enter Lambert-St Louis.

COVID-19 testing requirements
Visitors from Seattle/Tacoma Intl must present a negative RT-PCR (NAAT) or Antigen (quick-test) test taken 72 hours before departing to Lambert-St Louis.

Quarantine requirements
Visitors from Seattle/Tacoma Intl are not required to quarantine after entering Lambert-St Louis.

Do I need a test to fly back to Seattle from St. Louis?

Returning to Seattle/Tacoma Intl from Lambert-St Louis

COVID-19 testing requirements
Visitors from Lambert-St Louis must present a negative RT-PCR (NAAT) test taken 72 hours before departing to Seattle/Tacoma Intl.

Quarantine requirements
Visitors from Lambert-St Louis are not required to quarantine after entering Seattle/Tacoma Intl.

Hide COVID Travel Restrictions for St. Louis, MO

Destination information for St. Louis

Things to know before you go - useful duration and weather info for your trip from Seattle to St. Louis.
Average temperature for September in St. Louis
28.0 °C
Avg rainfall for September in St. Louis
76.0 mm

Airports servicing Seattle

Airports servicing St. Louis

Hourly flight availability from Seattle to St. Louis

See what time of day planes typically take off from Seattle towards St. Louis.
Morning 6 AM to noon 69% of flight departures
Early morning Midnight to 6 AM 16% of flight departures
Afternoon Noon to 6 PM 15% of flight departures
Evening 6 PM to midnight 0% of flight departures
Midnight
6 AM
Noon
6 PM
Weekly flight availability
from Seattle to St. Louis
See how many times per day planes take to the skies headed from Seattle to St. Louis.
Sunday
3 daily flights
Monday
4 daily flights
Tuesday
1 daily flight
Wednesday
1 daily flight
Thursday
4 daily flights
Friday
4 daily flights
Saturday
2 daily flights
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