$101 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 5/27. 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

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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.
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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
Seattle1 stop$230
Spokane
Spokane1 stop$347
Pasco
Pasco2 stops$432
Pullman
Pullman1 stop$541
Yakima
Yakima1 stop$544
Seattle
Seattle1 stop$230
Spokane
Spokane1 stop$347
Pasco
Pasco2 stops$432
Pullman
Pullman1 stop$541
Yakima
Yakima1 stop$544

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, May 27 - Fri, Jun 5
Frontier Logo
8:08 pm - 2:01 pm
STL
-
SEA
19h 53m
1 stop
Frontier Logo
7:50 pm - 7:23 pm
SEA
-
STL
21h 33m
1 stop
$230Frontier
Tue, May 26 - Wed, Jun 3
Frontier Logo
8:08 pm - 7:05 pm
STL
-
SEA
48h 57m
2 stops
Frontier Logo
7:50 pm - 7:23 pm
SEA
-
STL
21h 33m
1 stop
$246Frontier
Wed, Aug 26 - Sat, Aug 29
American Airlines Logo
8:00 am - 2:03 pm
STL
-
SEA
8h 03m
1 stop
American Airlines Logo
5:05 am - 4:14 pm
SEA
-
STL
9h 09m
1 stop
$254American Airlines
Wed, May 13 - Tue, May 19
Delta Logo
7:59 pm - 12:12 am
STL
-
SEA
6h 13m
1 stop
Delta Logo
11:59 pm - 10:32 am
SEA
-
STL
8h 33m
1 stop
$261Delta
Tue, Jun 9 - Wed, Jun 17
American Airlines Logo
5:03 pm - 12:41 am
STL
-
SEA
9h 38m
1 stop
American Airlines Logo
5:10 am - 4:33 pm
SEA
-
STL
9h 23m
1 stop
$269American Airlines
Sat, May 30 - Tue, Jun 2
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
$277Alaska Airlines
Fri, May 29 - Wed, Jun 3
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
$283Alaska Airlines
Tue, May 19 - Wed, May 20
Delta Logo
7:59 pm - 11:35 pm
STL
-
GEG
5h 36m
1 stop
Delta Logo
10:40 pm - 8:18 am
GEG
-
STL
7h 38m
1 stop
$347Delta
Tue, May 26 - Tue, Jun 2
Southwest Logo
3:45 pm - 10:55 pm
STL
-
GEG
9h 10m
2 stops
Southwest Logo
5:10 am - 1:30 pm
GEG
-
STL
6h 20m
1 stop
$407Southwest
Tue, May 26 - Tue, Jun 2
Southwest Logo
6:35 am - 1:05 pm
STL
-
GEG
8h 30m
2 stops
Southwest Logo
7:00 am - 5:55 pm
GEG
-
STL
8h 55m
2 stops
$412Southwest
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.

How much is a round-trip flight from St. Louis to State of Washington?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from St. Louis to State of Washington departing in May.

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 $331 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 $331.

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 in the evening, when round-trip flights cost $414 on average. Morning departures are around 19% 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 $492.

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 $399, 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 March, when tickets cost $80 (return) on average. On the other hand, the most expensive months are August and November, when the average cost of round-trip tickets is $169 and $129 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 42% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 6 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$101
Best time to beat the crowds with an average 25% drop in price.
Most popular time to fly with an average 7% increase 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 $273 one-way - $424 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 4314 reviews
7.0Food
8.0Comfort
8.1Boarding
8.6Crew
7.5Entertainment
Airline reviews

The entire experience from boarding to landing was amazing! The crew were very friendly. Will definitely be back.

10.0 Excellentlarry, Apr 2026
LGB - PHX
Read more Southwest reviews

The entire experience from boarding to landing was amazing! The crew were very friendly. Will definitely be back.

no service at all due to turbulence. they should've at least given us snacks, there were only 10 people on the entire flight.

First time I've had to use the disabled accommodations. And I could not have had a better experience with Southwest, i was having trouble getting from one terminal to another due to my heart failure. And the next thing I know a Southwest agent had made sure. I had a wheelchair at all my flights. Can't thank them enough.

Delayed flight, lack of information, boarding process is a mess as is the carryon luggage causing issues when leaving the plane….just a poor experience.

Comfortable. Easy. No problems. Just wish they had gf options for snacks.

The crew was very kind and made going to Hawaii relaxing and fun to look forward to! Thank you Southwest for a pleasant flight!

This leg was much better, but we did have to have a 3 hour lay o er after coming from a very exhausting hiccup with our flight from BNA to Den

We waited in the airplane for over 45 min for a southwest employee to make the flight. This cause over half the plane to miss their connecting flight in Denver. When we confronted the desk upon arrival, they told us the only flight they had was the next day leaving at 8:50 pm!!! Or they offered to get us to Burbank or LA, but after that we were on our own to get back to Santa Barbara. I paid for a flight from sba to bna bna to sba. My re entry into mom mode has been 💯 rough because of southwest mistake with my flight. And now I’m leaving to Reno tomorrow for a vballl tournament and just discovered that my leg in Vegas has me and my 3 kids on a stand by flight even though I had booked these ticket last year November!! Do better southwest!

Southwest is kind of a slum airline. It’s gotten more expensive over the years for less and less service. I am a Southwest Chase Visa card holder and was forced to choose a seat in the 26th row in the middle seat. However my wife who is a rewards member but doesn’t hold a card or anything else, gets randomly assigned a normally paid seat in row 6! How does that work?

For the first time in a long time, the Wi-Fi actually worked the entire flight! The flight crew was amazing as usual.

Our flight from Raleigh to Seattle delayed by hour plus. We missed connection as we couldn’t get to next gate in time Then we waited till 2:30 plane and then sat on tarmac loaded for half hour then our luggage couldn’t be found finally found where it was 2 employees sent us in wrong direction

They were really helpful with every question and my kids had never been on a plane and the staff made them feel comfortable

The merging of Kayak & the airline’s website was not always clear. Both on their own provided adequate Information about the flight. I had some challenges retrieving the boarding pass. I relied on the agent & may have paid the baggage fee twice.

Tucson AS767 flight yesterday from Tucson to SeaTac international Flight left Tucson around 7:44 am My name is Tanya Blendheim and I had a horrible experience yesterday morning at Alaska Airlines desk leaving from Tucson AZ. The agent was extremely rude and questioned everything about my trip. First she said (in a less than pleasant tone) you know your flight boards in 8 minutes? And we stop checking luggage 15 minutes before boarding. I acknowledged the first statement, but said that I didn't know about the check bag policy. (Another passenger, a man, was right behind me and he was denied checking his bag, which made him have to go back to his car to leave liquids behind) I also needed wheelchair assistance for my friend. I ended getting the wheelchair myself. The agent also said I wasn't checked in, which I was. One person in our group was no longer flying. She also said I had to pay $40 to check my bag and that my bag was 6 pounds over. The thing is, everything she said to me was said in a sassy tone and that was not professional or necessary. There are ways of informing customers of what is happening, without being condescending or rude.

very nice blankets and comfortable seats. great service. Great flights.

I’m biased. I work at the airport and within these systems so I know how to be effective. On top of that part though everyone was friendly and helpful. Both legs of my trip were on time. My baggage was handled with care. Alaska’s part of my experience was top notch.

Hello, Our flight arrived late, and the flight we were to connect to the departure time was moved up. At first our flight was scheduled to arrive at 10:40, but it arrived at 10:56. Our connecting flight was scheduled to leave at 11:25, and it was moved to 11:20. Also the terminal was moved from N to S. N would have been in the same terminal as the one we arrived in-- to get to S we had to take 3 trains to get to. And when we arrived at the gate, around 11:15, they said the gate was closed and would not open it. We had come from a funeral in Boston, and the person that helped us get new tickets said, "did you come from a girsl trip?" No, we did not. We were coming from a funeral. This experience was not what we expected/wanted. My friend, because she had to run to S, got a migraine and turned pale. In addition, I paid an extra $70 for an aisle seat that was more upfront, to make sure I can get off the plane faster and make the connecting flight. The fact that the plane not only did not wait, but left earlier, is absolutely unacceptable. This was a terrible experience, and I hope that I can be refunded for this horrible experience.

A gentleman at the desk for my boarding from Seattle to Anchorage randomly selected me and told me they would need to check my carry-on despite having multiple lithium-ion batteries all of which were in communication devices essential for time in Alaska. There was ample overhead compartment space and I was lucky non of my equipment was damaged due to his unnecessary use of power. A quick check with the flight crew would have likely resulted in an answer that ample space remained allowing me to keep my personal and important items near by. I did lose WiFi twice and that detracted from my entertainment which I do not commonly use.

The TSA pre check with photo linked to Alaskan airlines was extremely fast & convenient.

Flight was cancelled which destroyed the rest of our journey.

The agent at check in and at the gate were less than thrilled to be at work. I'm not a fan of Kayak's placement on the plane. I got put in the middle seat and none of my preferences were used.

In ATL they have two sets of departure screens. Follow what is on your airline's departure board - the ATL Airport Authority departure board had completely incorrect details about the gate assignment for my flight, which would have made me miss boarding.

Flight was delayed it was hot while sitting on the plane, one engine was working on the plane until they had to do some jimmy rigging down the runway in order for the other engine to charge up. It was ridiculous

Flight was delayed, we could have been notified earlier and in a consistent manner. App was not refreshing for another passenger to get the latest flight status. We could have stayed and waited at the hotel instead of waiting at the airport had we known the flight was going to delayed for more than 5 hours. The toilet is too tight, and needs to be cleaned more frequently (every hour). The entertainment screen froze, the touch screen not responding to touch. We were upgraded to comfort, it is more comfortable than regular economy seats.

It was fine. 55 minute flight. No snacks or beverage service offered. Boarding went smoothly and my walker was waiting for me on the jet way.

My flight was cencaled due with the bad weather on Sunday the crew was poorly mistaken my luggage supposed depart with my flight instead I didn’t have my luggage for almost 3 days the website is poorly respond to my complain until I have someone to do it my connection smooth their not even respon or email me even the have my luggage

8 hours late and the plane smelled like urine, that smell in the morning when your child wet the bed in the night.

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.

Flight delayed two hours , missed connection flight then connection cancelled- horrible experience with hotel

Omg the disaster at the security was on another level! “Go to this end, sorry closed now, go to that end”. Ridiculous! This took over an hour! As far as the airline was concerned although I booked nearly a year ago I couldn’t get my bag tag - stand in another 15 minute line or my seat on Hawaiian Airlines- 5 more minutes! Then my TSA status was denied. Like what the heck! Makes a person not want to travel with this amount of incompetence

The Honolulu Hub needs 2 to 3 times the amount of things to do as well as shuttles that transport to/from gates and terminals. Arriving from OCONUS locations; transferring to CONUS locations its a miserable experience. Fetching and re-checking bags, then returning to a gate across the airport take longer than any other large airport. If youre confused by what I mean, the process goes like this: Disembark plane Walk a mile to the main terminal Walk half a mile to baggage claim Wait 40 minutes for baggage Walk a mile to re-check-in baggage Wait 20 minutes for checking in those bags Fo back through the wrong TSA line because the signage is poor Almost miss the connecting flight because your gate is across the airport.

The checking was disaster, the crew wasn't behave well. It took us two hours to check in, after that thr line at the TSA was long, we barely make the flight. Bad airline

Fabulous if you have a portable wheelchair. They can store it in the galley and you can just walk out with it. Really nice and the flat seats are just incredible, very nice. iPads for movies, also pretty nice,

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.

Left early arrived early..right amount of talking from pilots..of course had to love the biscuit and water!

I would like a refund for the extra cost the seat I paid for. An oversized person sat next to me and I couldn’t fit on my seat and had to move to another seat.

Boarding gate at LAX was too crowded—two gates next to one another

The flight was delayed about an hour for a maintenance specialist to approve the maintenance repair

This flight was delayed but it worked in my favor because my Atlanta to Dallas flight was delayed.

This was a hard flight. 3 delays out of OKC (1 on the Tarmac). Delay in Atlanta coming to Dallas. total travel time was the equivalent of driving from OKC to Atlanta.

Like: flights are on time, good boarding process Can improve: planes are old, improve entertainment and make space more comfortable

Had to wait for a gate for a long time, then waited on the run way for a long time before leaving. The actual flights part was good.

The airplane was an old model, the overhead didn’t have enough room for people’s items and made boarding and boarding disappointing and stressful. Crew allowed passengers to bring more than the permitted baggage sizes.

Flying in the United States with the major airlines has become so underwhelming. A 2-3hr flight in most other parts of the world with the major carriers of the area comes with newer, CLEANER aircraft and significantly better in flight service in terms of both staff attitude and a actual meal service.

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

Information on your arrival and departure airports