Cheap flights from Seattle to St. Louis from $95
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from Seattle to St. Louis departing on 6/2. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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Southwest flights from Seattle to St. Louis
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United Airlines flights from Seattle to St. Louis
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How to get the cheapest flight ticket from Seattle to St. Louis
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to St. Louis?
In general, September is the cheapest month to fly from Seattle to St. Louis. Due to it being the ‘off-season’ during this time, you can expect flight prices to be around $316. The month of October is another great option to travel to St. Louis, with average flight prices from Seattle averaging around $337.
What is the cheapest day to depart on your flight to St. Louis?
The cheapest day to depart on your flight to St. Louis is on a Thursday when prices can be found for as low as $390. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Sunday because tickets tend to average around $487. These prices are subject to change though, so be sure to set up a Price Alert for flights to St. Louis.
What is the cheapest time of day to depart on your flight to St. Louis?
Flying to St. Louis from Seattle in the evening is the least expensive time of day to depart. momondo users have found prices as low as $267 when looking at flights departing in the evening. In the morning is when there is more demand to fly to St. Louis, so prices are often more expensive at around $440 per ticket.
What is the cheapest Seattle/Tacoma Intl to Lambert-St Louis flight route?
Fly from Seattle/Tacoma Intl to Lambert-St Louis for the best Seattle/Tacoma Intl - Lambert-St Louis flight prices
How far in advance should I book a flight to St. Louis?
You are more likely to see cheaper flights to St. Louis from Seattle when booking 21 weeks ahead of your departure date. In general, you can expect to find flights to St. Louis for around $386 when searching 21 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to St. Louis from Seattle for as low as $293 on momondo.
What cabin class options are available on Seattle/Tacoma Intl to Lambert-St Louis flights?
There are 4 cabin classes available to choose from on Seattle/Tacoma Intl to Lambert-St Louis flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.
What is the cheapest airline that flies from Seattle/Tacoma Intl to Lambert-St Louis?
Delta, Frontier, and United Airlines are the most popular carriers operating from Seattle/Tacoma Intl to Lambert-St Louis
What airlines fly to St. Louis?
Alaska Airlines, Delta and American Airlines are the top three most popular airlines that fly to St. Louis from Seattle according to our data. Alaska Airlines is the first choice among our users, with 68% of people opting to fly with this airline when traveling to St. Louis. Keep in mind that there are 7 different airlines that fly to St. Louis on a routine basis, so you have a few additional options to choose from.
How many flights depart from Seattle to St. Louis on average per day?
As of April 2025, 9 flights take off from Seattle and land in St. Louis each day. The most common flight departure time for this route is 6:00PM, with 64% of daily flights taking off in the evening.
How many flights depart from Seattle to St. Louis on average per week?
65 flights are operational weekly from Seattle to St. Louis as of April 2025. The most popular departure day for this route is Mon, with 18% of flights per week taking off on this day.
When to book flights from Seattle to St. Louis
Cheap Seattle to St. Louis (SEA to STL) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from Seattle to St. Louis
How far is Seattle/Tacoma Intl to Lambert-St Louis by plane?
The distance between Seattle/Tacoma Intl and Lambert-St Louis is about 1719.6 mi. Typically, this will take 3h 53m by plane in normal conditions.
When did momondo last update prices for flights from Seattle/Tacoma Intl Airport to Lambert-St Louis Airport?
Prices for flights from Seattle/Tacoma Intl Airport to Lambert-St Louis Airport are updated daily.
How many operators does momondo search for flights from Seattle/Tacoma Intl Airport to Lambert-St Louis Airport?
The number of operators available for flights from Seattle/Tacoma Intl Airport to Lambert-St Louis Airport is 7 as of April 2025.
How old do you have to be to fly from Seattle/Tacoma Intl Airport to Lambert-St Louis Airport?
The minimum age for a child to fly alone is five, but airlines offering an unaccompanied minor (UNMR) service may have their age restrictions, such as regulations concerning flight duration, timing, and layovers. It is recommended that you verify with the airline you are booking with for travel from Seattle/Tacoma Intl Airport to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The travel and health documents you'll need for your trip to Lambert-St Louis Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Lambert-St Louis Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular plane model from Seattle to St. Louis?
Based on momondo bookings for flights between Seattle and St. Louis, the leading plane model is Boeing 737, making up 38.49% of the total bookings. Other popular models include Boeing 737 MAX 9 with 19.80%, Boeing 737-900 Passenger/BBJ3 (winglets) with 18.81%, and Boeing 737-800 Passenger/BBJ2 (winglets) with 14.11%.
What is the most popular airline from Seattle to St. Louis?
momondo data reveals that the most frequently booked airline on the route from Seattle to St. Louis is Alaska Airlines, representing 63% of all bookings. The subsequent popular airlines are Delta at 12%, American Airlines at 9%, and Frontier at 6%.
Best airlines flying from Seattle to St. Louis
Compare and see reviews for airlines that fly from Seattle to St. Louis with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $141 | Free Cancellation | Rating 6.0 3,281 reviews | |||
| PriceFrom $186 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $188 | Free Cancellation | Rating 8.0 7,916 reviews | |||
| PriceFrom $216 | Free Cancellation | Rating 7.4 8,656 reviews | |||
| PriceFrom $216 | Free Cancellation | Rating 8.0 4,279 reviews | |||
| PriceFrom $236 | Free Cancellation | Rating 8.0 9,871 reviews | |||
| PriceFrom $237 | Free Cancellation | Rating 7.9 2,375 reviews |
Southwest Flights From Seattle to St. Louis
Southwest is one of the most popular airlines flying from Seattle to St. Louis, operating 3 flights/week on average for this route. A good Southwest flight deal for Seattle to St. Louis starts from $216 round-trip, up to an average price of $521. Our users have rated Southwest at 8.0/10.
Alaska Airlines Flights From Seattle to St. Louis
$236 is the best Alaska Airlines flight deal from Seattle to St. Louis found on momondo over the last 72 hours. The average Alaska Airlines ticket price found was closer to $417, however, with flight time and availability significantly affecting the price. Alaska Airlines (8.0/10 from 9,871 user reviews) flies into St. Louis from Seattle 7 times in an average week so prices can vary.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsWhy use momondo?
Why should I use momondo to find a flight deal from Seattle to St. Louis?
Finding the right flight to St. Louis from Seattle is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to St. Louis quick and easy, saving you time and money.
Can I find flights from Seattle to St. Louis with flexible booking policies on momondo?
Yes. All flights to St. Louis from Seattle on momondo can be compared and filtered by various policies on offer, including flexible booking.
How can momondo help me find flights from Seattle to St. Louis?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from Seattle to St. Louis.
I’m not ready to book a flight from Seattle to St. Louis right now. Can momondo alert me if prices change?
If you are simply researching potential flights to St. Louis, momondo offers a useful price alert feature which will track prices for flights to St. Louis from Seattle and alert you when they change.