How does KAYAK find such low prices on flights from Washington to St. Louis?

KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington to St. Louis.

How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington to St. Louis?

KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Washington is likely to change within 7 days, so travelers know whether to wait or book now.

What is the Hacker Fare option on flights from Washington to St. Louis?

Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to St. Louis with an airline and back to Washington with another airline.

What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington to St. Louis?

Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to St. Louis from Washington up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

$74 CHEAP FLIGHTS from Washington to St. Louis

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Flight Deals

Cheap Flights from Washington to St. Louis

Discover the best prices for you by selecting your travel dates on KAYAK.

Round-trip

One-way

Last minute

Direct

Recent round-trip flight deals from Washington to St. Louis

Wed, Oct 14 - Wed, Oct 21

3:14 pm - 12:19 amSEA Seattle/Tacoma Intl-STL Lambert-St Louis

7h 05m1 stop Chicago O'Hare Intl

8:48 am - 4:48 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

10h 00m1 stop Dallas/Fort Worth

$217American Airlines

Wed, Oct 14 - Tue, Oct 20

11:59 pm - 10:50 amSEA Seattle/Tacoma Intl-STL Lambert-St Louis

8h 51m1 stop Chicago O'Hare Intl

12:47 pm - 7:44 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

8h 57m1 stop Dallas/Fort Worth

$217American Airlines

Tue, Nov 10 - Tue, Dec 15

9:45 am - 8:29 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

8h 44m1 stop Detroit Metropolitan Wayne County

2:28 pm - 6:53 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

6h 25m1 stop Salt Lake City

$217Delta

Wed, Nov 11 - Sat, Dec 12

1:50 pm - 11:18 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

7h 28m1 stop Minneapolis St Paul

3:32 pm - 8:49 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

7h 17m1 stop Minneapolis St Paul

$217Delta

Wed, Dec 9 - Tue, Dec 15

6:10 am - 3:20 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

7h 10m1 stop Denver Intl

12:40 pm - 10:15 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

11h 35m2 stops Kansas City Las Vegas Harry Reid Intl

$222Southwest

Mon, Nov 9 - Wed, Nov 11

12:15 am - 11:00 amSEA Seattle/Tacoma Intl-STL Lambert-St Louis

8h 45m1 stop Chicago Midway

12:40 pm - 10:15 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

11h 35m2 stops Kansas City Las Vegas Harry Reid Intl

$222Southwest

Sun, Nov 22 - Tue, Dec 1

4:37 pm - 11:03 amSEA Seattle/Tacoma Intl-STL Lambert-St Louis

16h 26m1 stop Denver Intl

6:05 pm - 4:06 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

24h 01m2 stops Orlando Denver Intl

$243Frontier

Fri, Oct 2 - Mon, Oct 5

9:45 pm - 11:32 amSEA Seattle/Tacoma Intl-STL Lambert-St Louis

11h 47m1 stop Las Vegas Harry Reid Intl

8:10 pm - 3:08 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

20h 58m1 stop Denver Intl

$245Frontier

Wed, Oct 14 - Tue, Oct 20

6:03 pm - 11:59 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

3h 56mnonstop

7:02 am - 9:35 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 33mnonstop

$281Alaska Airlines

Wed, Dec 9 - Tue, Dec 15

6:06 pm - 11:59 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

3h 53mnonstop

7:00 am - 9:31 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 31mnonstop

$357Alaska Airlines

Recent last minute flight deals from Washington to St. Louis

Tue, Sep 15 - Tue, Sep 29

4:27 pm - 7:17 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

24h 50m1 stop Denver Intl

12:17 pm - 9:42 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

23h 25m1 stop Las Vegas Harry Reid Intl

$372Frontier

Thu, Sep 17 - Mon, Sep 28

4:27 pm - 7:17 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

24h 50m1 stop Denver Intl

8:10 pm - 3:08 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

20h 58m1 stop Denver Intl

$379Frontier

Fri, Sep 18 - Sat, Sep 19

11:57 pm - 10:18 amSEA Seattle/Tacoma Intl-STL Lambert-St Louis

8h 21m1 stop Chicago O'Hare Intl

1:54 pm - 8:07 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

8h 13m1 stop Charlotte Douglas

$445American Airlines

Wed, Sep 16 - Sat, Sep 19

9:45 pm - 11:17 amSEA Seattle/Tacoma Intl-STL Lambert-St Louis

11h 32m1 stop Las Vegas Harry Reid Intl

6:08 pm - 10:39 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

6h 31m1 stop Portland

$447Multiple Airlines

Wed, Sep 16 - Sat, Sep 19

8:00 am - 7:07 pmPDX Portland-STL Lambert-St Louis

9h 07m1 stop Dallas/Fort Worth

5:18 pm - 12:07 amSTL Lambert-St Louis-PDX Portland

8h 49m1 stop Chicago O'Hare Intl

$451American Airlines

Thu, Sep 17 - Mon, Sep 28

4:27 pm - 7:17 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

24h 50m1 stop Denver Intl

3:19 pm - 5:41 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 22mnonstop

$494Multiple Airlines

Tue, Sep 15 - Tue, Sep 22

12:54 pm - 8:38 pmPSC Pasco Tri Cities-STL Lambert-St Louis

5h 44m1 stop Denver Intl

4:40 pm - 8:37 pmSTL Lambert-St Louis-PSC Pasco Tri Cities

5h 57m1 stop Denver Intl

$511United Airlines

Tue, Sep 15 - Tue, Sep 22

12:54 pm - 8:38 pmPSC Pasco Tri Cities-STL Lambert-St Louis

5h 44m1 stop Denver Intl

12:59 pm - 8:37 pmSTL Lambert-St Louis-PSC Pasco Tri Cities

9h 38m2 stops Chicago O'Hare Intl Denver Intl

$516United Airlines

Tue, Sep 15 - Sat, Sep 19

11:45 am - 8:35 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

6h 50m1 stop Detroit Metropolitan Wayne County

8:00 am - 2:50 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

8h 50m1 stop Salt Lake City

$521Delta

Tue, Sep 15 - Sat, Sep 19

9:40 am - 5:37 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

5h 57m1 stop Salt Lake City

6:15 am - 10:39 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

6h 24m1 stop Minneapolis St Paul

$521Delta

Recent direct flight deals from Washington to St. Louis

Wed, Oct 14 - Tue, Oct 20

6:03 pm - 11:59 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

3h 56mnonstop

7:02 am - 9:35 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 33mnonstop

$281Alaska Airlines

Wed, Dec 9 - Tue, Dec 15

6:06 pm - 11:59 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

3h 53mnonstop

7:00 am - 9:31 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 31mnonstop

$357Alaska Airlines

Wed, Nov 11 - Wed, Nov 18

8:22 am - 2:25 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

4h 03mnonstop

7:00 am - 9:38 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 38mnonstop

$357Alaska Airlines

Tue, Oct 13 - Sat, Oct 17

6:03 pm - 11:59 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

3h 56mnonstop

4:42 pm - 7:10 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 28mnonstop

$357Alaska Airlines

Mon, Oct 19 - Thu, Oct 22

6:03 pm - 11:59 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

3h 56mnonstop

7:02 am - 9:35 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 33mnonstop

$365Alaska Airlines

Wed, Nov 11 - Sat, Nov 14

8:22 am - 2:25 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

4h 03mnonstop

6:00 am - 8:36 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 36mnonstop

$377Alaska Airlines

Tue, Nov 10 - Tue, Dec 15

8:22 am - 2:25 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

4h 03mnonstop

6:04 am - 8:50 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 46mnonstop

$377Alaska Airlines

Sat, Oct 24 - Wed, Oct 28

6:03 pm - 11:59 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

3h 56mnonstop

7:02 am - 9:35 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 33mnonstop

$377Alaska Airlines

Wed, Oct 14 - Sat, Oct 17

6:03 pm - 11:59 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

3h 56mnonstop

4:42 pm - 7:10 pmSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 28mnonstop

$437American Airlines

Wed, Nov 11 - Tue, Nov 17

8:22 am - 2:25 pmSEA Seattle/Tacoma Intl-STL Lambert-St Louis

4h 03mnonstop

7:00 am - 9:38 amSTL Lambert-St Louis-SEA Seattle/Tacoma Intl

4h 38mnonstop

$437American Airlines

Useful Info

Low season	January
High season	July
Cheapest flight	$74

Best time to beat the crowds with an average 8% drop in price.

Most popular time to fly with an average 8% increase in price.

Flight from Seattle to St. Louis

Verified travelerFlew with Alaska Airlines-Jul 2025

Give yourself extra time. Love the self check in options.

Verified travelerFlew with Alaska Airlines-Feb 2024

Be sure to measure your wheels for carry on my luggage was the correct size but the wheels made it over so had to check my bag wasn't happy about that since you have to pay for checked should at least get one free.

How does KAYAK find such low prices on flights from Washington to St. Louis?
KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Washington to St. Louis.
How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Washington to St. Louis?
KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to St. Louis from Washington is likely to change within 7 days, so travelers know whether to wait or book now.
What is the Hacker Fare option on flights from Washington to St. Louis?
Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to St. Louis with an airline and back to Washington with another airline.
What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Washington to St. Louis?
Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to St. Louis from Washington up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.