$72 Find Cheap Flights from St. Louis to Washington

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Washington departing on 4/13. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Washington

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Washington.
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Washington.
Travelers love KAYAK
41,299,237 searches in the past 7 days on KAYAK

Save 23% or moreCompare multiple travel sites with one search.

Track pricesNot ready to book? Create a price alert for when prices drop.

Bundle and saveSave money when you bundle your flight + hotel.

Filter your dealsChoose cabin class, free Wi-Fi and more.

Flight Deals
Booking Insights
Flight Deals

Cheap Flights from St. Louis to Washington

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Seattle
Seattle2 stops$197
Spokane
Spokane1 stop$239
Pasco
Pasco1 stop$367
Pullman
Pullman1 stop$297
Yakima
Yakima1 stop$327
Seattle
Seattle2 stops$197
Spokane
Spokane1 stop$239
Pasco
Pasco1 stop$367
Pullman
Pullman1 stop$297
Yakima
Yakima1 stop$327

Book Cheap St. Louis to Washington Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Washington that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

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

Wed, Apr 29 - Wed, May 6
Southwest Logo
5:30 am - 6:00 pm
STL
-
SEA
14h 30m
2 stops
Southwest Logo
11:40 am - 11:15 pm
SEA
-
STL
9h 35m
2 stops
$197Southwest
Mon, Apr 20 - Fri, Apr 24
Frontier Logo
9:55 pm - 9:27 am
STL
-
SEA
13h 32m
2 stops
Frontier Logo
7:12 pm - 7:32 pm
SEA
-
STL
22h 20m
1 stop
$204Frontier
Sat, Apr 4 - Sat, Apr 11
Hawaiian Airlines Logo
7:00 am - 9:35 am
STL
-
SEA
4h 35mnonstop
Hawaiian Airlines Logo
6:02 pm - 11:59 pm
SEA
-
STL
3h 57mnonstop
$205Hawaiian Airlines
Wed, Apr 8 - Sat, Apr 11
Hawaiian Airlines Logo
7:00 am - 9:35 am
STL
-
SEA
4h 35mnonstop
Hawaiian Airlines Logo
6:02 pm - 11:59 pm
SEA
-
STL
3h 57mnonstop
$206Hawaiian Airlines
Mon, Apr 20 - Wed, Apr 22
Frontier Logo
8:17 pm - 9:27 am
STL
-
SEA
15h 10m
1 stop
Frontier Logo
7:12 pm - 7:21 pm
SEA
-
STL
22h 09m
1 stop
$208Frontier
Wed, May 13 - Wed, May 20
Alaska Airlines Logo
7:41 pm - 10:11 pm
STL
-
SEA
4h 30mnonstop
Alaska Airlines Logo
9:17 am - 3:16 pm
SEA
-
STL
3h 59mnonstop
$215Alaska Airlines
Tue, Apr 14 - Tue, Apr 21
American Airlines Logo
5:21 pm - 10:56 pm
STL
-
PDX
7h 35m
1 stop
American Airlines Logo
11:47 pm - 8:24 am
PDX
-
STL
6h 37m
1 stop
$217American Airlines
Tue, May 19 - Tue, May 26
Alaska Airlines Logo
5:33 pm - 7:50 pm
STL
-
PDX
4h 17mnonstop
Alaska Airlines Logo
10:37 am - 4:37 pm
PDX
-
STL
4h 00mnonstop
$233Alaska Airlines
Wed, Apr 8 - Mon, Apr 13
Delta Logo
6:00 am - 11:37 am
STL
-
GEG
7h 37m
1 stop
Delta Logo
7:38 pm - 9:42 am
GEG
-
STL
12h 04m
2 stops
$332Delta
Wed, Apr 8 - Mon, Apr 13
Delta Logo
6:12 pm - 11:48 pm
STL
-
GEG
7h 36m
1 stop
Delta Logo
10:40 pm - 8:30 am
GEG
-
STL
7h 50m
1 stop
$351Delta
Booking Insights

KAYAK's insights & trends for St. Louis to Washington flights

Get data-powered insights and trends into flights from St. Louis to Washington to help you find the cheapest flights, the best time to fly and much more.

What is the cheapest St. Louis to Washington flight route?

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Washington from St. Louis found in the last 72 hours was to Seattle, at $209 round-trip. The most popular route is from St. Louis (STL) to Seattle (SEA), and the cheapest round-trip airline ticket found on this route in the last 72 hours was $209.

What is the cheapest time of day to fly to Washington?

The average price for all round-trip flights from St. Louis to Washington depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Washington is generally at night, when round-trip flights cost $418 on average. Morning departures are around 18% more expensive than evening flights, on average. The most expensive time of day to fly to Washington is generally in the morning, which is peak travel time and where the average cost of a ticket is $498.

Can I save money by flying with a layover from St. Louis to Washington?

The average round-trip price for all non-stop flights, flights with one layover, and flights with two layovers for the route found by users searching on KAYAK in the last 2 weeks.

No, with an average price for the route of $352, prices are generally cheapest when you fly direct.

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

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to Washington, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from St. Louis to Washington is February, when tickets cost $237 (return) on average. On the other hand, the most expensive months are July and June, when the average cost of round-trip tickets is $418 and $389 respectively.

What’s the cheapest day of the week to fly from St. Louis to Washington?

The average price of all round-trip flights from St. Louis to Washington clicked on KAYAK for each day over the last 12 months.

Your flight ticket price will generally be cheaper if you fly to Washington on a Tuesday and more expensive on a Sunday. On your return trip to St. Louis, you should consider flying back on a Tuesday, and avoid Mondays for better deals.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from St. Louis to Washington, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from St. Louis to Washington, you should book around 4 weeks before departure, which saves you about 43% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 10 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$72
Best time to beat the crowds with an average 24% drop in price.
Flight from St. Louis to Seattle

FAQs - booking Washington flights

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

    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 St. Louis to Washington.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from St. Louis to 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 St. Louis to Washington?

    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 from St. Louis to Washington with an airline and back with another airline.

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

    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 from St. Louis to Washington up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Top tips for finding cheap flights to Washington

  • Looking for a cheap flight? 25% of our users found tickets from St. Louis to the following destinations at these prices or less: Seattle $194 one-way - $300 round-trip

Reviews of the top 5 airlines serving from St. Louis to Washington

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to Washington. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from St. Louis to Washington? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
8.0
SouthwestOverall score based on 4319 reviews
8.6Crew
8.1Boarding
7.0Food
8.0Comfort
7.5Entertainment
Airline reviews

Long layover between flights to Long Island from BWI - need better coordination between flights

4.0 OkayKenny, Mar 2026
TPA - BWI
Read more Southwest reviews

Long layover between flights to Long Island from BWI - need better coordination between flights

I elected to pay for the upgrades and found very little difference

The new seating arrangement is so over priced for what you get.

The problem with the seat assignments is that there were a lot of rows in the front that were empty but my row at the back was full. Just not so pleasant.

No food or entertainment, just a quick 40 minute flight. A little bumpy due to Santa Ana winds but pilot has no control over that. Good flight and landing!

Good but I prefer choose your own seat. With the new assigned seats they should board from the back I see no advantage to this new boarding. Just like every other airline

I realize they are still working out kinks with the new boarding process, but by the time I boarded in group 5, most of the bins were full. All airlines should better enforce small bags and jackets going under the seats until everyone has boarded.

WiFi was not working and didn’t have a beverage service

Snacks are always pretzels. Why can't you also offer peanuts ?

Flight boarded late after announcing on time boarding. Flight arrived only a little late despite late departure. Had trouble connecting to WiFi

Snacks for our toddler could have been better, front the standpoint of variety but that’s not any different from other airlines.

Never got on because first part of trip was cancelled and we have no idea when we will get rebooked…

They cancelled the flight and provided no support to find another way home or how to get a refund. Links provided didn’t work and phone wait times were over eight hours. Battery on my phone couldn’t last long enough.

signage from the upper area to the tram down 2 escalator!

The WiFi worked for entertainment but a nearly 4 hour flight should have personal tvs

Generally very good. Waiting (due to de-icing and traffic) in plane to take off was a put-off. But it's not the airline's fault. I find Airbus more comfortable than Boeing.

Lot's of good food and free entanglement made the trip pleasurable and fun.

The food was terrible, worse that what you get with UA, an already one of the lowest standards to beat. How cheap one could be, providing that kind of junk food in first class. Unbelievable! The seats were not very comfortable either. And there were no screens either, not that I cared much but for you to know.

Easy check-in. Good customer service. Had to check carry-on due to lack of overhead space. Wish the airplane was configured with more overhead area so this doesn't usually happen.

Great flights, little turbulence, pilots kept stewardesses seated & safe, all staff friendly & professional

First class is comfortable. Enjoyed a movie and was able to relax compared to coach.

Loved flying First Class. Very comfortable. The seat was amazing. Enjoyed a movie and was able to relax so much better than in coach.

We landed and sat on the tarmac for 45 minutes because they only have one gate at the airport and there was another plane running late so we had to wait

Everything was good except wifi and a leaking drink chiller. The floor was all wet and my bag was soaked. Did not notice until debarking. Have not heard back from Delta. Even though this was leg one of an international flight in first class, they denied access to their Sky Club - very disappointing!

Delta has too many delays now days. It is 1:06 am now. I was supposed to land in Norfolk at 10:30 pm. I got re-booked through Detroit and I’m still in Detroit. I hope to be landed in Norfolk by 3am. I’ve been in airports for 12 hours as of right now. There is a weather delay now but most delays lately have been maintenance.

This is the first time I've been disappointed with Delta. I was called by Delta to see if I would volunteer to change flights since my original flight home was overbooked. I accepted. The modified booking only provided me a 35 minute layover - when you subtract the fact that boarding closes for a flight 15 minutes early, that gave me 20 minutes to run for one end of the airport to the other. I barely made it. On the 2.5 hour flight to Tampa, the crew repeatedly let us know over the intercom that they cannot serve drinks or snacks due to safety/turbulence. I would have accepted this reason if they did not CONTINUALLY SERVE DRINKS AND COOKED FOOD to First class. If safety is the excuse then the entire plane should be strapped in for safety. On top of this the air conditioning vents were not working correctly and the plane was uncomfortably warm. I love Delta and am a loyal Delta traveler, and I have never had an experience like this. I don't know if there's a disconnect between availability among third-party sites like KAYAK and the airlines or what, but when overbooking causes issues like this for travelers it should be reviewed and changes to the booking process should be made. I blame BOTH KAYAK and Delta for this terrible experience.

Prior to takeoff, the pilot told us there was a possibility of not being able to land and going to Portland. Well that happened, we took off and then did 8 loops around Spokane before the pilot told us we ran out of fuel and had to go to Portland. So for a 35 minute flight we have now been on the plane for 3 hours (boarded at 6:50 am and landed in Portland at 10:30). Then, we just sat in Portland's airport with no updates of when we can start heading back. All of a sudden, our pilots and crew just left, leaving us stranded in a different city and state. We continued to sit in Portland until we finally got a new crew assigned and boarded the plane (This was from 10:30-2). We then sat on the plane for an additional hour before take off because they had to count us multiple times. We finally landed in Spokane at 3:55 PM. So a flight that should have taken at max an hour took us 10 hours and we missed the majority of the recruiting event we went for.

Staff was great! Kind and cordial! Middle seat row 28 seat B has a hump in it. Trays were getting stuck when putting down and up. Good flight

This flight was no comparison to our prior flight. I'm thinking it all has to do with the age of the aircraft.

2 of the seats in row 31 the entertainment system was not working, and one seat the tray table did not go all the way down. Flight arrived early and departed on time which was great.

The crew were exceptionally nice and accommodating. My wife was tired after the flight from Haneda, Tokyo. They let her sleep and served her dinner later after she woke up, before we landed in PDX.

No charging outlets worked. Other than collecting trash attendants didn’t come around. No one could hear flight attendants announcements during the flight. Seat pads were horrible. Sitting on a board for 5 hours. What happened to Hawaiian airlines comfort, hospitality, and extras? Our pilots did an excellent job trying to minimize turbulence and incredible job in landing in windy conditions.

I like that if they asked you to checked in a bag at the gate they give you priority to board

Horrible food and crew. Crew were laughing and talking loud while people were trying to sleep

Yall need to integrate your system with Alaska more efficiently. They booted me off the first flight because of a discrepancy on your end.

The crew at Hawaiian Airlines was fantastic. Kind and hard working. The pilots were great with giving us all the updates to make sure we were informed.

Very good. Nice plane and we sat in economy plus - bigger seats, more room. They served a meal and snacks, and the meal was an apple stuffed pancake that was very good! The snack for us was a hummus sandwich - also very good. The flight attendants were helpful and nice. They have plenty of movies and shows to watch. My only negative -- they changed our flights around and did not adjust the layovers, so we ended up with a very long and unnecessary layover in Honolulu.

I liked the Starlink WiFi but didn't like how they said they were the only airline to offer a free meal and it turns out to be just a standalone sandwich and then charge for snacks to go with it. Rather have the free snacks like Southwest, but have the option to purchase a decent meal for a 5+ hour flight.

Flight scheduled to take off at 5.55pm but it did not take off until 7pm due to some food delivery delay.

Unfortunately, I was put into the middle seat in the first row of premium seating. Sounds nice right? No! that is the worst seat in the plane. I wish I was in economy rather than be in that seat! There is no seat back pocket, no tray table, no charger. Nothing! so unless you're row mates are willing to let you share their basic amenities any flyer should have, you are stuck. It was the worst experience ever! And the flight attendant forgot to take my drink order. I felt like the forgotten flyer.

After changing the departure gate 5 times making us mo e from one side of the airport to the other and then back the flight was delayed nearly 2 hours. The male flight attendant had a bad attitude with the guest being condescending, disrespectful with people who were already on edge.

Easy boarding. Rows are smaller but that may be an older and bigger me now :)

It would have been nice if American tried to care.

American Airlines did everything they could with the high Spring Break crowd. I was frustrated to be changed from 1st class to a middle seat at the back of the plane. This has happened before, not sure booking 1st class and paying the extra actually works.

I booked 1st class, my flights were changed and I was sitting in the middle at the back of the plane. A far cry from the 1st class I purchased for my flights. I am grateful I arrived on time.

There was no beverage service and the only time I saw a crew member walk through the cabin is when we were preparing to land.

Our flight was delayed 3 times and this is why I am giving such low reviews. Everything else was okay but being in the airport at 4:30pm for my initial flight at 7pm to not leave until after 9:30pm is insane,

Flights were constantly delayed. CRW took 50 minutes to get bags

Flight has been delayed every time I've ever taken it. Seats uncomfortable. Children behind me yelling the entire flight. Some of this is out of their control but overall just consistently not a great experience.

Check in was rough because the check in crew did not know how to manage my international visa documents. Required a long process and 4 people to finally be able to proceed to security. They told us incorrect information several times before acknowledging we did indeed have everything we needed from the start.

Everything you need to know for your flight from St. Louis to Washington

Information on your arrival and departure airports