$56 Find Cheap Flights from Washington, D.C. to St. Charles

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from Washington, D.C. to St. Charles departing on 11/19. 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.
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1 adult, Economy

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Cheap Flights from Washington, D.C. to St. Charles (WAS-STL)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Washington, D.C. to St. Charles 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 Washington, D.C. to St. Charles

Thu, Nov 13 - Mon, Nov 17
Frontier Logo
9:29 am - 10:20 amBWI-STL
25h 51m1 stop
Frontier Logo
2:12 pm - 10:20 amSTL-BWI
19h 08m1 stop
$144Frontier
Find Deal
Thu, Nov 13 - Fri, Nov 14
Frontier Logo
6:15 am - 10:12 amBWI-STL
4h 57m1 stop
Frontier Logo
4:56 pm - 12:13 amSTL-BWI
6h 17m1 stop
$145Frontier
Find Deal
Fri, Dec 5 - Fri, Dec 12
American Airlines Logo
7:21 pm - 11:06 pmBWI-STL
4h 45m1 stop
American Airlines Logo
5:58 pm - 11:33 pmSTL-BWI
4h 35m1 stop
$150American Airlines
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Mon, Dec 15 - Mon, Dec 22
Delta Logo
6:21 pm - 11:42 pmBWI-STL
6h 21m1 stop
Delta Logo
5:59 pm - 11:31 pmSTL-BWI
4h 32m1 stop
$177Delta
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Thu, Dec 4 - Sun, Dec 7
United Airlines Logo
8:30 am - 12:15 pmDCA-STL
4h 45m1 stop
United Airlines Logo
5:27 pm - 11:59 pmSTL-DCA
5h 32m1 stop
$242United Airlines
Find Deal
Tue, Nov 18 - Mon, Nov 24
American Airlines Logo
7:50 am - 9:20 amDCA-STL
2h 30mnonstop
American Airlines Logo
6:02 am - 9:14 amSTL-DCA
2h 12mnonstop
$246American Airlines
Find Deal
Sat, Dec 6 - Sun, Dec 7
Southwest Logo
12:20 pm - 1:40 pmDCA-STL
2h 20mnonstop
Southwest Logo
8:30 am - 11:25 amSTL-DCA
1h 55mnonstop
$249Southwest
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Sat, Jan 17 - Sun, Jan 18
United Airlines Logo
8:20 am - 2:28 pmIAD-STL
7h 08m1 stop
United Airlines Logo
3:11 pm - 9:17 pmSTL-IAD
5h 06m1 stop
$249United Airlines
Find Deal
Sat, Dec 6 - Sun, Dec 7
Southwest Logo
8:00 am - 9:20 amDCA-STL
2h 20mnonstop
Southwest Logo
7:55 am - 12:50 pmSTL-DCA
3h 55m1 stop
$255Southwest
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Tue, Nov 18 - Mon, Nov 24
Delta Logo
12:11 pm - 4:33 pmIAD-STL
5h 22m1 stop
Delta Logo
6:00 am - 11:42 amSTL-IAD
4h 42m1 stop
$266Delta
Find Deal

Everything you should know

Cheapest round-trip
$144
Overall average: $376
Frontier
Thu 11/13Mon 11/17
BWI - STL • 1 stop
Cheapest non-stop
$239
Typical prices: $284-$683
Southwest
Sat 2/14Wed 2/18
BWI - STL • Non-stop
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to St. Charles!
Useful Info

Good to know

Low seasonFebruary
Cheapest flight$56
Best time to beat the crowds but there is an average 10% increase in price.
Most popular time to fly and prices are also 10% lower on average.
Flight from Washington Dulles Airport to St. Louis

When to book flights from Washington, D.C. to St. Charles

Are your dates flexible? Find out the best times to travel from Washington, D.C. to St. Charles based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

FAQs for booking flights from Washington, D.C. to St. Charles

  • Which airports will I be using when flying from Washington, D.C. to St. Charles?

    When flying out of Washington, D.C. you’ll be using one of these airports: Washington, D.C. Reagan-National or Washington, D.C. Dulles Intl. St. Charles does not have its own airport so you’ll be flying into nearby Lambert-St Louis airport, which is 7.2 mi away.

  • How long does a flight from Washington, D.C. to St. Charles take?

    Direct flights cover the 717 miles separating Washington, D.C. and St. Charles in about 4h 45m.

  • How many flights are there between Washington, D.C. and St. Charles?

    32 direct flights run between Washington, D.C. and St. Charles on a daily basis. On average, there are about 228 departures each week.

  • What’s the cheapest day of the week to fly between Washington, D.C. and St. Charles?

    Consider leaving on a Thursday and avoid Wednesdays if you are looking for the best rates. For your return to Washington, D.C., you’ll find the best rates on Fridays and the most expensive ones on Wednesdays.

  • How does KAYAK find such low prices on flights from Washington, D.C. to St. Charles?

    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, D.C. to St. Charles.

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

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

    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. Charles with an airline and back to Washington, D.C. with another airline.

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

    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. Charles from Washington, D.C. up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

  • Which airlines provide the cheapest flights from Washington, D.C. to St. Charles?

    In the last 72 hours, the cheapest one-way ticket between Washington, D.C. and St. Charles found on KAYAK was with Frontier for $56. Frontier offered a round-trip connection from $144 and American Airlines from $150.

Top tips for finding cheap flights from Washington, D.C. to St. Charles

  • There is no airport in St. Charles. Instead, you’ll be flying into St. Louis Lambert Airport when flying between Washington, D.C. and St. Charles.
  • The cheapest flight from Washington, D.C. to St. Charles was found 66 days before departure, on average.
  • Book at least 2 weeks before departure in order to get a below-average price.
  • High season is considered to be September, October and November. The cheapest month to fly is August.

Reviews of the top 5 airlines serving Washington, D.C. to St. Charles

 
Need help choosing which airline to fly with from Washington, D.C. to St. Charles? 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 4238 reviews
8.1Boarding
7.0Food
8.0Comfort
7.5Entertainment
8.6Crew
Airline reviews

Great flight. Outstanding Service. Southwest was able to put us on a direct flight to Denver when the connection could have been affected by a later arrival to Baltimore. The direct flight was less expensive that the flight with the connection in Baltimore.

10.0 ExcellentAnonymous, Oct 2025BOS - BWI
Read more Southwest reviews

Great flight. Outstanding Service. Southwest was able to put us on a direct flight to Denver when the connection could have been affected by a later arrival to Baltimore. The direct flight was less expensive that the flight with the connection in Baltimore.

Delays delays delays. Late taking off, late landing, wait for a gate, etc.

Boarded on time but once we were ready for take off, the crew determined that, although every seat was taken, somehow someone was on the wrong flight. Delay, delay delay, announcements and ended up with one person checking EVERY ID against their passenger Manifest only to figure out it was a "clerical error." We departed 54 minutes late causing me to run in the St. Louis Airport to make my connection and lose the priority boarding spot I had paid for. Unnecessary delay.

I was re-booked onto another flight because my original flight was delayed and I would have missed my connector. I ended up in the “C” group after paying extra to be in the “A “ group on the original flight. At least if you’re going to re-book people, re-book them into the same group.

Flight was delayed due to plane not passing inspection And one of the crew had to time out and we had to wait for another one A 3 hour delay

mandatory demand customer to check their carry on because not enough people check bags.

Connecting flight is on time and boarding was a breeze!

Excellent. Would encourage Southwest to keep current boarding procedures with free style seating. Makes for a fantastic experience

As always, the entire Southwest experience was perfect. Purchasing the tickets on the Southwest web site was effortless, departure and arrival gates were spotless and comfortable, plane was clean and comfortable, crew was excellent and flight was on time. Wheelchair service in Las Vegas at departure was somewhat chaotic and disjointed, but I am not sure if that was Southwest problem, airport problem or combination.

I wish they had movie screens in the headrests. The seats are much improved, more legroom and recently renovated. Bathroom was clean. Staff was outstanding!!

The flight used a B767 with a very old interior from before 2014. The entertainment system did not work at all during the flight despite attempts to reset the system. It was like they flew this route just to be competitive.

They changed planes and the new plane couldn’t carry enough fuel to fly across the country so we had to stop in Kansas City to refuel. Flight was delayed .

Flight was too crowded and seats are too small, especially since passengrs are getting larger. Having a middle seat is ALWAYS tough! Woman on my left was large & kept creeping in to my space. Flight personnel were great! Have more savory rather than sweet snacks please.

Flight was crowded and the woman sitting on my left was large & kept crouching in to my space. You need bigger seats or smaller passengers to fit into the seats you DO have! Snack were OK. Would appreciate if airlines had more savory rather than sweet snacks, thank you!

Delayed flight (1hour) plus a long layover after an overnight flight with no backup plane available.

We were delayed, which I think had to do with air traffic control. Otherwise, everything was great.

The boarding process needs to be refined. Sometimes the gate crew calls out the zones and then flip to showing the.zones boarding on the gate monitor display. So, unless you are huddled around the gate lanes watching the monitor, you could miss your boarding zone. Suggest the zones be announced each time a new zone is allowed to board.

The boarding process needs to be refined. Sometimes the gate crew call out the boarding zone, and then flip to the monitor to show which zones are boarding. So unless everyone is gathered around to see the monitor there is usually confusion as wi which zones are boarding.

On time flight. Seat comfort could be better in the Comfort section.

My issue was with TSA agents for delta airlines. My luggage got flagged. The agent was going thru another persons first. He took 20 min to go thru hers. I asked them to bring mine closer so I could sit down . They said you can go sit it will be fine. I said I am supposed to keep my eyes on my bags at all times. The agent was meticulously unwrapping 2 gifts that the lady had and then tried to re warp it. He was trying to be kind i get it but 20 min for me to stand watching him do that was ridiculous. It was 6 am and there were a ton of travelers. Mine was flagged for some air packed tea that I bought in Turkey. My previous delta flight and 2 others before didn’t flag it. Consistency would be nice. Also on the flight the window shades were down for take off and landing - I thought that was very odd I thought they had to remain open for take off and landing.

During booking, I kept trying submitting my payment from the Mexican website and it didn't work. After I had the idea to change it to the Canadian website, it worked but I had to be charged the equivalent of 50 CAD more. I received the clear instruction that I would only be able to check-in at the airport and that it was impossible to select a seat 24 hours before departure, that I had to pay 144 CAD to do so, although not only was I able to check-in 24 hours before departure, but I could have selected my seats for free then. All in all, I almost threw $200 out the window due to misleading information. Besides, the app kept crashing, the information to get to the gate on the app was inaccurate, my gate was switched and I was only informed once in the air (luckily I had noticed the departure pannel), I was not addressed in my language beforehand and even if I tried I was immediately answered in English (which meant the crew understood but didn't want to answer accordingly), there was only one snack & beverage service on my medium haul flight and no beverage service on my short haul flight. To be fair, the planes were comfortable, the crew apart from the language issue was helpful, dynamic and engaging, the plane was clean and the directions were clear and direct. United has a lot of potential to be one of my favourite airlines, but the devil is in the details and a lot of them missed the target.

Better WiFi. I cannot understand that in 2025, United is so behind on a technology that is now a necessity and still painfully unreliable, slow and keeps disconnecting.

Great service on board. Boarding a bit slow due to process. Food was pretty average.

Very small cramped plane for an international flight. Everything else was good, but it was maybe the smallest comfort-wise I've ever been on for longer than 3-4 hours and the trip was 7.5

Flight was delayed 3 hours. No food and drink vouchers was provided. They offered a mini pretzel bag and water .

Staff was rude. Didn’t give water for 2 hours. Worst service

Was on time until within 1 hour of flight-how does that happen? Staff very friendly.

I liked the choice of lemon ginger tea. I think stewardesses can be more considerate of older people needs.

We were given vouchers we couldn’t use with a 5.5 hour delay

I fly UAL 7-8 times per year. This flight was not up to snuff because it boarded very late "due to unexpected delays in restocking the plane" and yet Flight Aware showed the plane had landed some 10 hours earlier--so I think they could have planned accordingly. The FA's were nice but harried. The video system had to be rebooted 3-4 times. The food service was rather abrupt; they forgot my row and when I asked for my meal, they brought it with some impatience. Overall, the flight was fine, but the little details made it feel somewhat mundane and hurried.

It took way too long to diagnose and solve the problem of a broken crew member cabin seat. Though compensation for the volunteer who left the flight was very kind.

We fly American Airlines quite a bit. And we always fly business class when traveling internationally. We were a bit disappointed with the comfort of this particular plane as well as the entertainment options.

The AA staff person who checked our bags was curt and almost rude. The FA also seemed unhappy doing her job. Overall it was like riding the school bus back in grade school.

They are still charging me after taking 466 and 833 for round trip from AR to to Bradley airport from 19 to 21. Then poor experience. Am hurt and I will say it on social media. Please stay away from this airline. I see in my bank account they are still taking 644. Am trying to stop it. I used to fly United airlines and I suggest that if you don't want extra charges and good service you go back there. American airlines delayed my flight again and I was late for my meeting, no recompensation but charging me over and over.

They changed our Gate 5 times, and concourse twice. Changed our seats twice.

Pitch was very small. Knees were on the seat back in front of me.

Wonderful as usual except for other guests that were unruly and not kept in check by the Crew.

The flight was initially delayed, then cancelled. American Airlines says the cancellation was weather related, though the actual weather was not bad in both Washington and Providence and between. There were very few cancellations that day. In fact, AA2120 from Washington, DC to Boston flew with a minor delay at about the same time. So, the weather somehow affected only this particular flight AA5230. The next available flight was the following morning. The American Airlines refused to reimburse accommodation (hotel at DCA)

Fine. On time, cabin service was fine, bag arrived. All good. Flying into DCA so did not collide with any helicopters, which is also good. Horrid incident that could have and should have been prevented.

Good experience but the snacks are not gluten free, so I cannot eat them.

Boarding was on time and plane departed as scheduled. There are obviously no amenities (food, drink, entertainment) on Frontier, but there also didn't seem to be any issues with luggage space either.

Inbound plane was on time and flight departed on time with no issues while boarding.

I knew going into this that Frontier, being a low cost carrier, would be pretty bare bones and charge for most extras but this was made up for by the fact that the airplane was a reasonably new Airbus, every employee was great and best of all, Everett Washington is an amazing airport - thanks Frontier for flying there!!!

i was unable to check in the flight. refund requested

It was well done. It was my first time flying with them and I was nervous b/c I have heard of many cancelled and/or delray flights. Everything went smoothly.

Just know that everything, and I mean everything is “ala cart”. 60$ just to put something in the overhead bin. I will never fly Frontier again nor do I recommend them to anyone else.

The single worst check in experience I could imagine. I’ll never do any business with Frontier or any affiliated company

Too many extra fees, uncomfortable, little leg room. Will not recommend this airline.

Everyone seemed to be in zone 1 for boarding. Maybe break it up a little. Otherwise, smooth flight.

Frontier is the Walmart of airlines. Frontier has removed adjustability and comfort from their seats to make the flight lighter and save gas. This makes it impossible to sleep on their flights. Their customer service is abysmal. Once, I bought a drink on the plane, and they swiped my credit card on the plane to pay for it. Then I got three weeks of daily notices from my bank telling me they tried to charge the wrong card number over and over again. I tried to call them, but they removed the ability to actually talk to someone that can resolve such a problem from their company to cut corners. The only way to talk to someone in person is to go to the check-in counter at the airport (40 minutes drive from my house). Eventually their system gave up on trying to charge the card, after 21 days of repeated tries. They don't pad their prices even a little to handle customer service issues like missed flights. They also have a blanket policy preventing helping you reschedule a missed flight if their system says you "cancelled" your own flight online. This is a major problem because their website is broken on mobile devices, the only web browser you have at the airport when their gate staff tell you that you have to reschedule your own missed flight online because they can't help you. I tried to reschedule my flight on my android device and instead, their website crashed and "cancelled" my missed flight. When I got to the counter, the agent argued with me for 5 minutes insisting that I intentionally cancelled my own flight (implying I had to buy another flight). She missed the point: the problem was that I could not buy another flight because their website is broken. I left to avoid more conflict with the "customer service" agent. I tried to redress my issue with their only other "customer service" chanel available: the contact form on their website. The response I got was more of the same: you cancelled your own flight, according to our website / computer records, therefore we won't help you. I was trying to explain the problem with their broken website that cost me hundreds of dollars by crashing / malfunctioning and resulting in a cancelled flight, but they only had deaf ears for this problem. Worst customer service I have ever experienced. I will never buy another Frontier flight again, because it is a risky, painful move that I will likely regret often.

Everything you need to know for your flight from Washington, D.C. to St. Charles

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