$66 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 2/25. 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.
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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$162
Spokane
Spokane1 stop$272
Pasco
Pasco1 stop$338
Pullman
Pullman1 stop$373
Yakima
Yakima1 stop$377
Seattle
Seattle1 stop$162
Spokane
Spokane1 stop$272
Pasco
Pasco1 stop$338
Pullman
Pullman1 stop$373
Yakima
Yakima1 stop$377

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, Mar 11 - Fri, Mar 13
Frontier Logo
8:12 pm - 11:09 am
STL
-
PDX
16h 57m
1 stop
Frontier Logo
12:04 pm - 9:49 am
PDX
-
STL
19h 45m
1 stop
$152Frontier
Sat, Feb 28 - Sat, Mar 7
Southwest Logo
6:10 am - 1:50 pm
STL
-
SEA
9h 40m
1 stop
Southwest Logo
10:30 am - 1:55 am
SEA
-
STL
13h 25m
1 stop
$162Southwest
Wed, Mar 11 - Sun, Mar 15
Frontier Logo
8:12 pm - 11:09 am
STL
-
PDX
16h 57m
1 stop
Frontier Logo
12:04 pm - 9:49 am
PDX
-
STL
19h 45m
1 stop
$167Frontier
Tue, Mar 10 - Fri, Mar 13
Delta Logo
3:05 pm - 8:48 pm
STL
-
SEA
7h 43m
1 stop
Delta Logo
1:32 pm - 12:21 am
SEA
-
STL
8h 49m
1 stop
$177Delta
Sat, Mar 7 - Tue, Mar 10
American Airlines Logo
6:36 pm - 12:24 am
STL
-
SEA
7h 48m
1 stop
American Airlines Logo
11:59 pm - 8:55 am
SEA
-
STL
6h 56m
1 stop
$184American Airlines
Tue, Mar 10 - Fri, Mar 13
Delta Logo
2:22 pm - 6:28 pm
STL
-
SEA
6h 06m
1 stop
Delta Logo
1:32 pm - 12:21 am
SEA
-
STL
8h 49m
1 stop
$185Delta
Sat, Feb 28 - Sat, Mar 7
Hawaiian Airlines Logo
2:47 pm - 5:26 pm
STL
-
SEA
4h 39mnonstop
Hawaiian Airlines Logo
7:55 am - 1:51 pm
SEA
-
STL
3h 56mnonstop
$186Hawaiian Airlines
Tue, Jun 2 - Tue, Jun 9
Alaska Airlines Logo
6:20 pm - 8:37 pm
STL
-
PDX
4h 17mnonstop
Alaska Airlines Logo
11:18 am - 5:06 pm
PDX
-
STL
3h 48mnonstop
$229Alaska Airlines
Sat, Feb 28 - Fri, Mar 6
American Airlines Logo
6:36 pm - 12:17 am
STL
-
PDX
7h 41m
1 stop
American Airlines Logo
11:40 pm - 8:55 am
PDX
-
STL
7h 15m
1 stop
$249American Airlines
Tue, Mar 3 - Wed, Mar 4
Alaska Airlines Logo
7:00 am - 2:36 pm
STL
-
GEG
9h 36m
1 stop
Alaska Airlines Logo
5:40 am - 1:51 pm
GEG
-
STL
6h 11m
1 stop
$277Alaska Airlines
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 $227 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 $227.

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 $347, 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 October, when tickets cost $249 (return) on average. On the other hand, the most expensive months are July and June, when the average cost of round-trip tickets is $437 and $417 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 Thursday, and avoid Sundays 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 3 weeks before departure, which saves you about 32% compared to booking last minute. For the absolute cheapest price, our data suggests you should book 11 weeks before departure.

Good to know

Low seasonJanuary
Cheapest flight$66
Best time to beat the crowds with an average 14% drop in price.
Most popular time to fly with an average 5% 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.

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

    The cheapest time of day to fly to Washington is generally in the evening, when round-trip flights cost $449 on average. Morning departures are around 13% more expensive than evening flights, on average. The most expensive time of day to fly to Washington is generally in the afternoon, which is peak travel time and where the average cost of a ticket is $510.

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 $214 one-way - $325 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
Alaska AirlinesOverall score based on 11808 reviews
7.0Entertainment
7.1Food
8.1Boarding
7.8Comfort
8.5Crew
Airline reviews

The staff was extremely helpful and accommodating. The only thing I could have done without was the long layover in between flights but I was going to a less popular destination so it was understandable.

10.0 ExcellentAnonymous, Jan 2026
RNO - SEA
Read more Alaska Airlines reviews

The staff was extremely helpful and accommodating. The only thing I could have done without was the long layover in between flights but I was going to a less popular destination so it was understandable.

All went well, right on time, easy boarding. We ordered the evergreens grain bowl and were surprised and pleased how adequate it was for vegan lunch! Landing was smooth and gate exit was easy

My seat and tray were filthy. Someone’s used straw was in the seat pocket and there were coffee stains and food crumbs on the tray table

On time, good boarding process very quick. Clean planes. Planes are tight, not much leg room ( i am only 5'8"). Some attendants are moving through aisles fiercely and pushing passengers. Got yelled for a tiny man bag that it is an extra personal tem ( size of a wallet) Wi-Fi on the plane does not work well with android phones.

I didn’t go, and can’t use a no refundable ticket.

good food and service and the seats were much better than anything comparable provided by US airlines. The entire experience was light years better than flying with a US company.

On time departure and early arrival giving more than ample time for connecting flight.

Flights were on time, easy boarding, comfort, flight was smooth.... Best travel experience I have ever had

Second flight in a row that I've been on where the auto bag counter stopped working and they had to manually count cargo before takeoff. Also second flight where my whole fruit and cheese plate looked pretty stale/old. The grapes were very strange tasting to the point where I didn't eat them. Apple slices were just sad/gross looking so also avoided those.

inflight entertainment website was extremely slow to load on my phone

All good except once again bags took an hour at Midway Airport Happens all the time. Ridiculous

Everything went smoothly and we even arrived a little bit early.

Great vacation. Can't wait till next year for another one.

Great flight but super high price. Glad it was a business trip and not personal

On time. Friendly staff. Took to long to pre bord all the specialty groups. Cramped small plane

The seats were comfortable, and the boarding process was pretty smooth.

3 hour delay. Had to change plans and was still delayed.

The staff was very friendly, professional, and courteous. The overall flight was a great experience.

The crew canceled the complementary snack and drink in anticipation of turbulence that never materialized. I was counting on the drink (water) to take the the doses of medication - prescribed for my heart condition - that were due during the flight. Since no snack or meal was served on this flight, I cannot rate the food quality. Otherwise, this flight was excellent.

Departure was delayed more than 1/2 hour while we waited for luggage (only) transfer from another flight/plane. Once approved for takeoff, the flight was excellent.

Delta One is extraordinary. I fly business when somebody hires me. I just wonder why there is such a chasm between business class and the insanely inhumane and nonsensical coach. The seats are not large enough to fit even my tiny wife. We fly 10% of what we did because we don’t want to pay 5-10 k but for $400 it’s unbearable. It seems like the accountants took over and made stupid decisions. Screw in 20 extra seats and make it so unbearable that people fly 90% less. Just put the damn price up and put some proper chairs in. But business, yay.

Timing, quality of service, promptness and courtesy of the staff

It was last minute due to weather - considering - it was amazing! Good smiles, friendly staff and they were making sure we knew what was going on when and where.

delta last minute gave me a boarding pass for a different flight with no confirmation that they were changing it

The service from the flight attendants were of supreme quality. They greeted and treated everyone with a wide smile. This is totally absent nowadays. Kudos to them!!!!

Excellent flight and got us around tough weather. Only issue was seat TV did not work and crew tried to reboot.

Very large passenger too space from my own seat. Arm board couldn’t be lowered because of his size. It wads very uncomfortable trip, as the flight was full couldn’t move anywhere having back pain because of the position in which I was the entire flight.

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.

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.

Delayed and cancelled flights were hard and very stressful, both ways!

The crew was quite good, they came by often with drinks or to collect trash. But what wasn't nice was the flight was over weigh and several people had to be rebooked. I was questioned whether I should have a seat when I was getting to it. The in-flight entertainment kept buffering and interrupting. And the route took the airplane through high winds which caused us a longer flight

Wasn’t on the flight due to Alaska cancellation…also after all the rerouting, I was going to be on a later flight that left SFO at 7:47pm, which meant an almost 6 hour layover. That same Hawaiian flight was delayed for another 2hours.

I had to cancel the flight because with a 3 hour delay for 'unexpected maintenance' in getting to LAX, I couldn't connect to an overseas flight that I had booked on Scandinavian Air.

No gates avail at DFW so our incoming had to wait 30 mins for a plane to push back because they Had mechanical. We boarded 90 mins delayed and then we had a mechanical. Come on American…do better. Also at my seat the tray table had not been cleaned. Floor had not been cleaned. But captain and flight Att were very picture and apologetic.

Crew was helpful and cheerful especially when they had no refreshments to work with. The plane was never serviced and had nothing but limited water and coffee onboard. For the price point, a concern of services.

Flight was smooth, quick and felt safe. The 2 delays not happening would have been better but I guess that happens in the airline industry

Flight was canceled. I asked to be rerouted to OKC and then took an Uber.

AA did not allow to board a flight because my connecting flight from DFW had been canceled. I got on another flight to another city. No service on the plane and I did not use their entertainment system.

On time on a day with lots of weather cancellations on other flights. Thank you for getting me home during a winter storm!

Don't change gate multiple times make people run across the airport. Announce delays in a timely manner. Have maintenance crew ready. Don't delay and keep passengers on the plane for 3 hrs. on tarmac.

The plane was experiencing problems with the HVAC system, it was very cold in the front of the plane and very hot in the back.

The attendants were kind and helpful. A sugar-free drink would have been very welcome.

Pilot navigated severe weather/snow storm with skill. Described his intentions clearly

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

Information on your arrival and departure airports