Cheap Flights from Seattle to St Louis from $290

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Flight deals from Seattle to St Louis Airport

Looking for a cheap last-minute deal or the best return flight from Seattle to St Louis Airport? If you want to travel next month, return fares start from $290. Find the lowest prices on one-way and return tickets right here.

St Louis.$290 per passenger.Departing Wed, 15 Apr, returning Wed, 22 Apr.Return flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departs from Seattle / Tacoma International on Wed, 15 Apr, arriving in St Louis.Inbound indirect flight with Southwest Airlines, departs from St Louis on Wed, 22 Apr, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $290, select.

St Louis.$318 per passenger.Departing Sun, 3 May, returning Wed, 6 May.Return flight with Frontier Airlines.Outbound indirect flight with Frontier Airlines, departs from Seattle / Tacoma International on Sun, 3 May, arriving in St Louis.Inbound indirect flight with Frontier Airlines, departs from St Louis on Wed, 6 May, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $318, select.

St Louis.$319 per passenger.Departing Sat, 25 Apr, returning Sat, 2 May.Return flight with Frontier Airlines.Outbound indirect flight with Frontier Airlines, departs from Seattle / Tacoma International on Sat, 25 Apr, arriving in St Louis.Inbound indirect flight with Frontier Airlines, departs from St Louis on Sat, 2 May, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $319, select.

St Louis.$396 per passenger.Departing Wed, 10 Jun, returning Mon, 15 Jun.Return flight with Frontier Airlines.Outbound indirect flight with Frontier Airlines, departs from Seattle / Tacoma International on Wed, 10 Jun, arriving in St Louis.Inbound indirect flight with Frontier Airlines, departs from St Louis on Mon, 15 Jun, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $396, select.

St Louis.$427 per passenger.Departing Wed, 9 Sep, returning Wed, 16 Sep.Return flight with United.Outbound indirect flight with United, departs from Seattle / Tacoma International on Wed, 9 Sep, arriving in St Louis.Inbound indirect flight with United, departs from St Louis on Wed, 16 Sep, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $427, select.

St Louis.$428 per passenger.Departing Wed, 1 Jul, returning Tue, 14 Jul.Return flight with United.Outbound indirect flight with United, departs from Seattle / Tacoma International on Wed, 1 Jul, arriving in St Louis.Inbound indirect flight with United, departs from St Louis on Tue, 14 Jul, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $428, select.

St Louis.$430 per passenger.Departing Mon, 12 Oct, returning Fri, 16 Oct.Return flight with Delta.Outbound indirect flight with Delta, departs from Seattle / Tacoma International on Mon, 12 Oct, arriving in St Louis.Inbound indirect flight with Delta, departs from St Louis on Fri, 16 Oct, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $430, select.

St Louis.$465 per passenger.Departing Tue, 30 Jun, returning Wed, 22 Jul.Return flight with Frontier Airlines.Outbound indirect flight with Frontier Airlines, departs from Seattle / Tacoma International on Tue, 30 Jun, arriving in St Louis.Inbound indirect flight with Frontier Airlines, departs from St Louis on Wed, 22 Jul, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $465, select.

St Louis.$577 per passenger.Departing Thu, 23 Jul, returning Mon, 10 Aug.Return flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departs from Seattle / Tacoma International on Thu, 23 Jul, arriving in St Louis.Inbound indirect flight with Southwest Airlines, departs from St Louis on Mon, 10 Aug, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $577, select.

St Louis.$584 per passenger.Departing Sun, 23 Aug, returning Sat, 29 Aug.Return flight with Southwest Airlines.Outbound indirect flight with Southwest Airlines, departs from Seattle / Tacoma International on Sun, 23 Aug, arriving in St Louis.Inbound indirect flight with Southwest Airlines, departs from St Louis on Sat, 29 Aug, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $584, select.

St Louis.$687 per passenger.Departing Thu, 23 Jul, returning Mon, 10 Aug.Return flight with Alaska Airlines.Outbound direct flight with Alaska Airlines departs from Seattle / Tacoma International on Thu, 23 Jul, arriving in St Louis.Inbound direct flight with Alaska Airlines departs from St Louis on Mon, 10 Aug, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $687, select.

St Louis.$693 per passenger.Departing Mon, 20 Apr, returning Tue, 21 Apr.Return flight with Alaska Airlines and Hawaiian Airlines.Outbound direct flight with Alaska Airlines departs from Seattle / Tacoma International on Mon, 20 Apr, arriving in St Louis.Inbound direct flight with Hawaiian Airlines departs from St Louis on Tue, 21 Apr, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $693, select.

St Louis.$899 per passenger.Departing Thu, 26 Mar, returning Mon, 30 Mar.Return flight with Delta.Outbound indirect flight with Delta, departs from Seattle / Tacoma International on Thu, 26 Mar, arriving in St Louis.Inbound indirect flight with Delta, departs from St Louis on Mon, 30 Mar, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $899, select.

St Louis.$903 per passenger.Departing Tue, 31 Mar, returning Sat, 4 Apr.Return flight with Delta.Outbound indirect flight with Delta, departs from Seattle / Tacoma International on Tue, 31 Mar, arriving in St Louis.Inbound indirect flight with Delta, departs from St Louis on Sat, 4 Apr, arriving in Seattle / Tacoma International.Price includes taxes and charges.From $903, select.

Find the cheapest month to fly from Seattle to St Louis

We’re always keeping an eye on fares, so you can find the best one in seconds. It looks like Seattle to St Louis flights are currently cheapest in April.

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Direct flights from Seattle to St Louis

Seattle to St Louis: Alternative routes

Compare routes from Seattle to St Louis below. You may find an airport to fly into that's cheaper, faster, or easier than St Louis.

Seattle to St Louis: Flight information

The things to know before you go.

Cheapest flight found	$290
Cheapest month to fly	April
Average flight time	3 hrs, 58 mins
Most popular airline	Alaska Airlines
Average flights per week	55

Finding cheap flights from Seattle to St Louis: Frequently asked questions

How much are return flights from Seattle to St Louis?

The best price we found for a return flight from Seattle to St Louis is $290. This is an estimate based on information collected from different airlines and travel providers over the last 4 days and is subject to change and availability.

How long does it take to fly from Seattle to St Louis?

3 hours and 58 minutes is the average flight time from Seattle to St Louis.

Which airlines fly direct from Seattle to St Louis?

Alaska Airlines, American Airlines and Qatar Airways fly direct from Seattle to St Louis.

How many flights are there a week from Seattle to St Louis?

As of March 2026, there are 55 flights per week flying from Seattle to St Louis.

When is the cheapest time to fly from Seattle to St Louis?

The cheapest month to fly from Seattle to St Louis is usually April.

Which upcoming date is cheapest to fly from Seattle to St Louis Airport on?

After crunching the numbers on our flight calendar, we found that it is currently cheapest to fly from Seattle to St Louis Airport on Wednesday, 15 April 2026.

Can I get a direct flight from Seattle to St Louis Airport?

Yes – the average flight time is 3 hours and 58 minutes.

How can I find the best flight deal to St Louis?

We show every price from over 1,200 airlines and travel agents, comparing them all so you don’t have to. If you know you want to fly to St Louis but you’re not ready to book, set up a Price Alert. We’ll track prices for you, and let you know when they rise or fall.

When is the best time to book flights to St Louis?

We crunched all the numbers in our flight calendar and it looks like the cheapest time to book a flight to St Louis is around 40 days in advance, so don’t leave your flight to the last minute.

Travelling from Seattle to St Louis Lambert International Airport (STL): What you need to know

Seattle's main airport is Seattle-Tacoma International Airport (SEA). Explore your options for departing from here when reserving your flights from Seattle to St Louis Lambert International Airport (STL).
The average duration of a direct Seattle to St Louis Lambert International Airport flight is 3 hours 55 minutes.
The timezone in St Louis is UTC-6, which is two hours ahead of Seattle. St Louis Lambert International Airport is located in St Louis.
Seattle-Tacoma International Airport (SEA) to St Louis Lambert International Airport (STL) is the busiest route. You can select from 16 direct weekly services between SEA and STL.
For a stress-free journey, turn up at the airport two hours ahead of international flights and an hour before domestic departures. This will give you plenty of time to board your flight from Seattle to STL.
Travelling during a peak time like July? Popular periods (like Thanksgiving, Christmas/New Year and spring break) can add another hour at check-in and security. Play things extra safe and arrive up to four hours ahead of international flights and two hours before domestic departures.

Airports in Seattle

Seattle-Tacoma International Airport (SEA)

Seattle-Tacoma International Airport (SEA) offers an easy route to your destination. Nonstop flights from Seattle to St Louis Lambert International Airport (STL) can be booked from this terminal.
Alaska Airlines is a well-known carrier that operates direct flights from Seattle to St Louis Lambert International Airport taking off from SEA.
The preferred choice for passengers flying between SEA and STL is Alaska Airlines.
Alaska Airlines ranks as the leading on-time carrier on this route, with 84.16% of its services landing on schedule.
SEA is about 23 kilometres from central Seattle. If you're catching a taxi, driving or ride-sharing from the centre, it'll take you 25 minutes or so to get there, depending on traffic conditions. If you're planning to take public transport, expect the journey time to be around 35 minutes.
Want a relaxed start to your trip? Stay near Seattle-Tacoma International Airport. Whether you have an early flight from Seattle to St Louis Lambert International Airport or just don't want to be rushed, these hotels are the answer:
Seattle-Tacoma International Airport scores high marks for on-time performance. 80% of flights that depart SEA arrive at their destination on time.

Seattle Paine Field International Airport (PAE)

PAE is about 40 kilometres from central Seattle. It'll take 40 minutes or so to get to the airport if you're driving from the city centre. Public transport takes approximately 1 hour 30 minutes.
Start your holiday sooner with an extra night away from home. Before your Seattle to STL flight, unwind in one of these hotels close to Seattle Paine Field International Airport:
Seattle Paine Field International Airport has a track record for punctuality. 80% of flights out of here arrive right when they're supposed to.

About St Louis Lambert International Airport (STL)

Book a hotel near STL if you're catching a late flight from Seattle to St Louis Lambert International Airport. Pick one of these options and call it a night faster:
Booking your ride around one week ahead of your Seattle to St Louis Lambert International Airport flight can help you secure the lowest rate.
STL is located at 10701 Lambert International Blvd..

Getting from St Louis Lambert International Airport (STL) to central St Louis

St Louis Lambert International Airport is around 24 kilometres from central St Louis. It takes around 25 minutes or so to get to the city by car.
It'll take around 30 minutes when travelling by public transport.

How to find the cheapest flights from Seattle to St Louis Lambert International Airport (STL)

The lowest price we've found for a one-way ticket from Seattle to St Louis Lambert International Airport is $145. For a return flight on this route, the best price is $290. Depending on the availability when you book, these fares could change.
Don't wait until the last moment. You're more likely to find cheap flights from Seattle to STL if you book ahead. Airlines often have some fantastic early bird rates.
If you have some flexibility with your trip dates, use the 'Whole month' search tool. It'll give you the lowest price in each month when searching for your Seattle to St Louis Lambert International Airport ticket.
Snapping up a cheap plane ticket from Seattle to STL is easy with Price Alerts. All you need to do is set up one of these automatic alerts and we'll let you know when a better deal is available.
Filters make it easier to track down a bargain for your flight from Seattle to St Louis Lambert International Airport. Pick the airlines, flight times and number of stops that look good to you. Then sort the results by 'Cheapest' to find the best price quickly.

The best time to fly from Seattle to St Louis Lambert International Airport (STL)

Think about your travel style when deciding when to fly. December is the quietest month to go to St Louis. July is when most people book flights from Seattle to St Louis Lambert International Airport (STL), which may be ideal if you'd rather travel when it's busy.
Lock in a Seattle to STL plane ticket departing in July if you want to experience the city during its warmest month. Expect temperatures in St Louis to range from 17ºC to 33ºC.
Look for cheap tickets from Seattle to St Louis Lambert International Airport in January if you'd rather travel when it's cooler. Temperatures are at their lowest then, ranging between -7ºC and 8ºC.

More about St Louis

After booking your flight from Seattle to St Louis Lambert International Airport, choose a hotel that puts you where you want to be. Make one of these options your base for exploring St Louis:
Your St Louis visit should come with a side of sightseeing. Highlights you can't miss include The Gateway Arch, Saint Louis Arch and Museum at the Gateway Arch.

Explore more of the United States

St Louis has loads to offer, but there are so many other corners of the United States waiting to be discovered. About 257 kilometres east of St Louis, a trip to Evansville will keep you on the move. Start with leading attractions like Mesker Park Zoo, Riverfront Park and Evansville Museum of Arts, History & Science.
Columbia is another must-experience destination in the United States and is around 177 kilometres west of St Louis. No trip is complete without a visit to Museum of Art and Archaeology, Mizzou Botanic Garden and Francis Quadrangle.