$71 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 10/16. 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, Sep 25 - Mon, Sep 29
Frontier Logo
6:22 am - 3:04 pmBWI-STL
9h 42m1 stop
Frontier Logo
4:00 pm - 12:17 amSTL-BWI
7h 17m1 stop
$143Frontier
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Sun, Sep 7 - Sun, Sep 21
Frontier Logo
6:22 am - 3:04 pmBWI-STL
9h 42m1 stop
Frontier Logo
1:52 pm - 3:17 pmSTL-BWI
24h 25m1 stop
$144Frontier
Find Deal
Tue, Sep 23 - Tue, Sep 30
American Airlines Logo
2:49 pm - 6:32 pmBWI-STL
4h 43m1 stop
American Airlines Logo
2:11 pm - 9:32 pmSTL-BWI
6h 21m1 stop
$217American Airlines
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Tue, Sep 23 - Sat, Oct 4
United Airlines Logo
10:51 am - 2:19 pmBWI-STL
4h 28m1 stop
United Airlines Logo
3:23 pm - 9:22 pmSTL-BWI
4h 59m1 stop
$227United Airlines
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Tue, Sep 23 - Tue, Sep 30
Southwest Logo
6:55 pm - 8:05 pmDCA-STL
2h 10mnonstop
Southwest Logo
3:15 pm - 6:15 pmSTL-DCA
2h 00mnonstop
$237Southwest
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Tue, Oct 28 - Wed, Oct 29
Southwest Logo
3:45 pm - 6:35 pmDCA-STL
3h 50m1 stop
Southwest Logo
1:05 pm - 4:05 pmSTL-DCA
2h 00mnonstop
$243Southwest
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Wed, Sep 17 - Thu, Sep 18
American Airlines Logo
7:50 pm - 9:10 pmDCA-STL
2h 20mnonstop
American Airlines Logo
10:54 am - 1:58 pmSTL-DCA
2h 04mnonstop
$245American Airlines
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Sat, Sep 20 - Tue, Sep 23
United Airlines Logo
8:40 am - 10:02 amIAD-STL
2h 22mnonstop
United Airlines Logo
8:15 am - 11:25 amSTL-IAD
2h 10mnonstop
$245United Airlines
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Wed, Sep 17 - Thu, Sep 18
Delta Logo
6:00 am - 9:59 amIAD-STL
4h 59m1 stop
Delta Logo
10:40 am - 4:07 pmSTL-IAD
4h 27m1 stop
$265Delta
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Wed, Sep 17 - Thu, Sep 18
Delta Logo
6:00 am - 9:59 amDCA-STL
4h 59m1 stop
Delta Logo
6:42 pm - 11:42 pmSTL-DCA
4h 00m1 stop
$265Delta
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Useful Info

Good to know

Low seasonFebruary
Cheapest flight$71
Best time to beat the crowds but there is an average 13% increase in price.
Most popular time to fly with an average 4% increase in price.
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 28m.

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

    23 direct flights run between Washington, D.C. and St. Charles on a daily basis. On average, there are about 161 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 Tuesdays if you are looking for the best rates. For your return to Washington, D.C., you’ll find the best rates on Thursdays and the most expensive ones on Sundays.

  • 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 $71. Frontier offered a round-trip connection from $143 and Spirit Airlines from $203.

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 61 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 February, March and April. 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 4242 reviews
7.5Entertainment
7.0Food
8.1Boarding
8.0Comfort
8.6Crew
Airline reviews

AC sub par. WiFi not working correctly. Ac sucked. Seats very narrow.

2.0 MediocreMike, Aug 2025AUS - BWI
Read more Southwest reviews

AC sub par. WiFi not working correctly. Ac sucked. Seats very narrow.

Near 4 hour flight with only 1 service. Had to use call button to request water. Internet and power not working until into flight. Internet would stop working during flight.

Southwest's seats are the least comfortable I have ever sat in.

The cabin was quiet for the redeye flight. The area was clean. The staff was great. The 787 Max was in good condition. Drawbacks were that the seat widths were tight for some passengers. The seat padding was at best average and for a long flight uncomfortable.

Southwest like most American domestic airlines, is a mediocre airline. But it is among the cheapest. Oh well.

My flight was delayed 50 minutes and we were rushed to board to then sit for 15 minutes until the pilot arrived. Unacceptable since we could have waited to board. Also the delayed flight was updated AFTER we boarded to more than the 10 minutes as originally stated.

Other than a bit of a delay, everything was good. Again, the boarding process and picking seats is the only thing I don't enjoy.

If we are going to have to pay for luggage, make it easier to do. Put something on the app during check-in so I don't need to do it at the kiosk. I've done it twice recently and I ended up having to pay at the desk because something went wrong at the kiosk in Tampa.

southwest just starting charging for luggage. hadnt realized it until it was too late. now out $70 when i couldve bought a carry on if i wouldve known. free bags was one of the only reasons i chose southwest over another airline (the other being no assigned seats, which is apparently also being changed). stupid business decision. wont be flying southwest anymore.

The quality of Southwest Airlines continues to degrade each time I fly with them. If it were not for the free luggage, I would probably choose another airline. Their prices are a little bit competitive, but way too high for the quality of the service. Southwest is not unique in this way. Domestic flight in the United States of America has continued to be a lower and lower quality product. Very sad when you compare the quality of domestic airlines to that of many international airlines around the world.

This route with Delta always has delays or is cancelled. Aircrafts seem smaller and older. I fly Delta quite a bit - haven’t had issues with the international flights. But this route has always been the troublesome one

Three seats in first class were broken and while they were able to still acommodate us it was looking very touch and go and they had others they could not acommodate

Mechanic delay in addition to a 2 hour change in takeoff time was frustrating.

Delayed due to thunderstorms and no in-flight service due to rough weather — both of which are out of Delta’s control. Flight was good overall.

The flight attendants in SLC were rude. I arrived 40 minutes early to gate. Ticket said I needed check in for seat assignments and tried check in and attendants said they weren’t doing it. And proceeded to never call me to give me a ticket so when time to board I received the very last seat. Please relay to employees to do their job better..,

On this flight I felt the food offering was not as complete as on previous flights. The tomato salad was a bit off and there was nothing additional such a bread or butter. The breakfast was only one option, so you either ate what they had or ate nothing. The crew was efficient, but most seemed frustrated throughout the flight. The flight arrived early and was obstacle-free, so I’m overall quite happy, but the shine in the rest of the experience just wasn’t there.

The seats got pretty uncomfortable pretty fast. The armrests are bigger than on other planes, so I had less room in the actual seat. My butt hurt by the end of the flight. :/ comfort was the primary issue. The crew were fantastic!

I believe that a four-hour trip should have a meal. Delta had none.

Great flight with Delta! Boarding was quick and easy, the amenities were solid, and the plane was in great shape. The flight attendants had a fun, lively energy while staying professional. All in all, a smooth trip — even managed to catch up on some rest. Thanks, Delta!

I was uncomfortably cold on the plane. Other than that it was uneventful and therefore as enjoyable as a plane ride can be.

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.

I didn’t get on plane. Passport being processed by consulate with visa application. Tried to cancel through underpricer after purchasing cacelling for any reason. No dice, they are thieves.

When I booked it on Kayak it aaid that I wasn't allowed hamd luggage. I called United Airlines and it took them 6 minutes to figure out if I was allowed free hand luggage. Surely something that simple they should be able to tell me instantly.

We were delayed in Toronto on the tarmac for THREE hours with no clear indication as to why except that it was not a safety hazard. Pilot did apologize more than once but even he was unable to explain why exactly we were delayed. I overheard the stewards saying that the captain was very frustrated with the situation as well because he was not able to explain why except it had something to do with water supply or system on the aircraft and now we needed to wait for an engineer to approve the aircraft for flight. It was very frustrating and distressing as a passenger and we should have been given complimentary meals at the very least.

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.

Standard. No different than a discount carrier on a short trip.

Everything was great. Boarding, early departure, early arrival, and deplaning were smooth. Smooth flight.

Great for the price. No wifi or entertainment, but gate agents and crew were fantastic and we boarded quickly and left on time.

sluggish boarding and arrival procedures, fake nice flight attendants, and lots of delays.

Disaster. They lied every step of the way. We ended up being delayed due to crew and then allegedly abandoned the flight because of a curfew at LGA. No rebooking to LGA at any reasonable time. No hotel. No meal vouchers. Had to sleep in the airport and fly to Newark instead. Will never fly Frontier again.

What I expected, nickeled and dined and a frontier flight attendant loudly complained about her job and lack of communication as she headed to the gate on her cell phone. Not professional.

As every law enforcement agency I could imagine surrounded the plane and we didn’t disembark for 2 hours and then had to stick around for another hour to go get our personal belongings after leaving them behind and being bused away from the plane, it was scary and inconvenient. We were given no information as to why this was happening. Lack of communication with passengers was disappointing.

After boarding and un-boarding twice over 6+hours, the flight was canceled.

Severe turbulence. Captain never came on to reassure passengers after things settled down.

My first flight was delayed 5 hours. The 2nd flight was canceled til the next day and the never even tried to compensate for it. Worse I was delayed again on the flight the rebooked me on.

Boarding in Orlando was not good. Giant mob at the gate, should have been lines.

Decent clean onboard experience. Okay discount airline experience. Unfortunately, any customer service interactions are difficult and unhelpful. There is no service. Also, a premium seat only gets you premium boarding if you line up first. Once they start general boarding you must go to the back of the line. Not very premium

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

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