Cheap flights from Seattle to St. Louis

22 Mar — 29 Mar1
1 adult
Wed 22/3
Wed 29/3

The best prices from Seattle/Tacoma Intl to Lambert-St Louis are usually found in April or January, booked 45 days in advance, depart on a Wednesday or Thursday and return on a Monday

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 2023: compare Seattle to St. Louis flight prices with the expected peak season, weather and rainfall in St. Louis.



C$ 299 - C$ 593



0 - 27 °C



56 - 119 mm

Popular inJuneHigh demand for flights, 29% potential price rise
Cheapest inAprilBest time to find cheap flights, 29% potential price drop
Average priceC$ 481Average for round-trip flights in March 2023
Round-trip fromC$ 411From Seattle/Tacoma Intl to Lambert-St Louis

Users have found that leaving on a Tuesday can be a cost-effective option. It’s possible to save up to 219% on your flight compared to booking on days when demand is much higher.

To save on the cost of your flight from Seattle to St. Louis, book at least 44 days before your planned departure. Booking around this time can save you about 60% on the cost of this flight compared to booking a flight leaving this week. We have found prices from C$ 657 if you need a flight within two weeks. For flights within the next 72 hours, you can find tickets from as low as C$ 893.

The best pricing can be found in the month of April. Prices to St. Louis from Seattle average C$ 579. You can even find prices in April for less than C$ 579, as users have found deals to St. Louis from as low as C$ 272. The month of June 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 40%.

A simple way to save on the total cost of your ticket is to fly from Seattle to St. Louis in the morning. If you’re flexible enough to do this you can expect to save up to 28% on your trip compared to booking a flight at noon.

Related info for your journey

Useful info, stats and facts about Seattle to St. Louis flights.

Direct flights are available for this route on the following days: Monday, Wednesday.

Per day, 5 flights depart from Seattle to St. Louis on average.
Evening (6pm - Midnight) - 100% of flight departures

The top 3 most reliable airlines when flying from Seattle to St. Louis are Qatar Airways (97%), Japan Airlines (96%) and American Airlines (94%).

Great question - SEA to STL just means Seattle/Tacoma Intl Airport to Lambert-St Louis Airport. Now you’ll know what these unique codes when you look for flights!

Top airline flying from Seattle to St. Louis

The chart below displays the airlines Cheapflights users travelling from Seattle to St. Louis choose most often. Cheapest and average prices are based on aggregated data from the past 12 months.
AirlineCheapestAverageFlexibilityOn-timeCOVID-19 safety
Alaska AirlinesCheapestC$ 341AverageC$ 618FlexibilityNo cancel feeOn-time75%COVID-19 safety
Search Alaska Airlines flights

Hourly flight availability from Seattle to St. Louis

See what time of day planes typically take off from Seattle to St. Louis
1%of flight departuresEarly morningMidnight to 6 am
58%of flight departuresMorning6 am to noon
41%of flight departuresAfternoonNoon to 6 pm
0%of flight departuresEvening6 pm to midnight
6 AM
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
Sunday7daily flights
Monday3daily flights
Tuesday3daily flights
Wednesday7daily flights
Thursday9daily flights
Friday3daily flights
Saturday3daily flights
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