$67 Find Cheap Flights from Washington, D.C. to St. Charles - Compare and Save

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 9/6. 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, 0 bags

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Everything you should know

Cheapest round-trip
$134
Typical prices: $159-$188
Frontier
Wed 10/7Mon 10/12
BWI - STL • 1 stop
Cheapest non-stop
$253
Typical prices: $332-$507
Southwest
Fri 9/4Sun 9/6
DCA - STL • Non-stop
Arrival airport
You can't fly directly to St. Charles. It is served by St. Louis (STL), located 7.2 miles from St. Charles.
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Flight Deals
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Flight Deals

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

Wed, Oct 7 - Mon, Oct 12
Frontier Logo
9:25 pm - 9:40 amBWI  Baltimore/Washington-STL Lambert-St Louis
13h 15m1 stop Atlanta Hartsfield-Jackson
Frontier Logo
10:35 am - 8:57 amSTL  Lambert-St Louis-BWI Baltimore/Washington
21h 22m1 stop Atlanta Hartsfield-Jackson
$134Frontier
Mon, Sep 14 - Mon, Sep 21
Frontier Logo
6:00 am - 1:10 pmBWI  Baltimore/Washington-STL Lambert-St Louis
8h 10m1 stop Atlanta Hartsfield-Jackson
Frontier Logo
2:29 pm - 4:46 pmSTL  Lambert-St Louis-BWI Baltimore/Washington
25h 17m1 stop Atlanta Hartsfield-Jackson
$139Frontier
Sat, Sep 5 - Sun, Sep 6
Southwest Logo
3:40 pm - 7:35 pmDCA  Washington, D.C. Reagan-National-STL Lambert-St Louis
4h 55m1 stop Chicago Midway
Southwest Logo
7:30 pm - 10:30 pmSTL  Lambert-St Louis-DCA Washington, D.C. Reagan-National
2h 00mnonstop
$247Southwest
Sat, Sep 5 - Sun, Sep 6
Southwest Logo
11:45 am - 7:50 pmDCA  Washington, D.C. Reagan-National-STL Lambert-St Louis
9h 05m1 stop Tampa
Southwest Logo
1:10 pm - 4:10 pmSTL  Lambert-St Louis-DCA Washington, D.C. Reagan-National
2h 00mnonstop
$247Southwest
Sat, Sep 5 - Fri, Sep 11
American Airlines Logo
8:09 pm - 11:58 pmDCA  Washington, D.C. Reagan-National-STL Lambert-St Louis
4h 49m1 stop Chicago O'Hare Intl
American Airlines Logo
6:00 am - 9:19 amSTL  Lambert-St Louis-DCA Washington, D.C. Reagan-National
2h 19mnonstop
$247American Airlines
Sat, Sep 5 - Fri, Sep 11
United Airlines Logo
8:25 am - 9:39 amIAD  Washington, D.C. Dulles Intl-STL Lambert-St Louis
2h 14mnonstop
United Airlines Logo
9:40 am - 4:01 pmSTL  Lambert-St Louis-IAD Washington, D.C. Dulles Intl
5h 21m1 stop Chicago O'Hare Intl
$247United Airlines
Sat, Sep 5 - Sun, Sep 6
United Airlines Logo
5:45 pm - 7:11 pmIAD  Washington, D.C. Dulles Intl-STL Lambert-St Louis
2h 26mnonstop
United Airlines Logo
6:00 am - 11:52 amSTL  Lambert-St Louis-IAD Washington, D.C. Dulles Intl
4h 52m1 stop Chicago O'Hare Intl
$247United Airlines
Sat, Sep 5 - Sun, Sep 6
Delta Logo
2:54 pm - 8:33 pmIAD  Washington, D.C. Dulles Intl-STL Lambert-St Louis
6h 39m1 stop Atlanta Hartsfield-Jackson
Delta Logo
1:04 pm - 8:05 pmSTL  Lambert-St Louis-IAD Washington, D.C. Dulles Intl
6h 01m1 stop Atlanta Hartsfield-Jackson
$257Delta
Sat, Sep 5 - Sun, Sep 6
Delta Logo
6:00 am - 11:56 amIAD  Washington, D.C. Dulles Intl-STL Lambert-St Louis
6h 56m1 stop Atlanta Hartsfield-Jackson
Delta Logo
5:30 pm - 11:26 pmSTL  Lambert-St Louis-IAD Washington, D.C. Dulles Intl
4h 56m1 stop Detroit Metropolitan Wayne County
$257Delta
Fri, Sep 11 - Mon, Sep 14
American Airlines Logo
7:59 pm - 9:24 pmDCA  Washington, D.C. Reagan-National-STL Lambert-St Louis
2h 25mnonstop
American Airlines Logo
6:00 am - 9:19 amSTL  Lambert-St Louis-DCA Washington, D.C. Reagan-National
2h 19mnonstop
$258American Airlines
Useful Info

Good to know

Low season

January

Cheapest flight

$67
Flight from Baltimore 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 2h 10m.

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

    18 direct flights run between Washington, D.C. and St. Charles on a daily basis. On average, there are about 126 departures each week.

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

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

  • 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 5 days, the cheapest one-way ticket between Washington, D.C. and St. Charles found on KAYAK was with Frontier for $60. Frontier offered a round-trip connection from $78 and Delta from $124.

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 49 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 June, July and August. The cheapest month to fly is October.

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 4214 reviews
7.5Entertainment
8.1Boarding
8.6Crew
8.0Comfort
7.0Food
Airline reviews

Just crazy with times being pushed and pushed and pushed and gate crew at Philly super rude and unprofessional with many under stress with delays.

2.0 MediocreHans, Aug 2026
Read more Southwest reviews

Just crazy with times being pushed and pushed and pushed and gate crew at Philly super rude and unprofessional with many under stress with delays.

Great job! My family doesnt fly often but we felt safe 100%

Communication about the delayed flight was poor. We were told to move gates three times but that was bad information. We went from gate 128 to gate 126 and then to gate 123 and back to gate 126. Communication about the delay was bad. Ended up being 1 1/2 hour late getting home.

I have roller bag with food and medication told me I couldn't bring on my 2nd flight today. 15 years flying with SW never an issue with that bag.

I have not flown Southwest in awhile and had a very pleasant experience. From ticketing to boarding to the flight. The flight left on time and landed ahead of schedule. It won't be so long next time!!

Haven’t flown on SW in years. Flight was on time departing and arriving. Served vegan butter onion flavored pretzels which were bad. Coke served was in a tiny paper cup. Crew was not engaging. Felt like they were going through the motions. Old plane, tight seats and no leg room.

No delays and arrived to destination 30 min early. Staff was super friendly.

Pretty standard flight. We left late, but arrived early. The wifi entertainment is always nice. The free snacks and beverages are simple, but appreciated. I'm tall and the seats are an issue. I can deal with a short flight, but any longer, I have to find another airline where I know beforehand I have extra legroom.

Awesome experience. No in-flight video or meal. Still do not like the boarding process.

On time, good crew, easy flight. Just like the old days!

Long delays at both DCA and MSP; Crew did not keep us informed (or very little). Airplane was showing signs of heavy use (not up to Delta standards). Food options for Business Class have dropped in quality. After landing we sat on tarmac for maybe 25 minutes with no provided chance to use the bathroom and crew did not tell us what was going on or give an estimated time to expect to be at a gate.

Flight was delayed for about an hour but overall good experience

The gentleman at the gate I think his name is RIE was exceptional

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.

Waited at the usual crowded gate at DCA where one ends up standing up because there aren't enough seats.

Delayed take-off. Very small plane so very scary with lots of bumps during the flight. Would never fly Delta on short flights in small 80 seaters plane again! Felt relieved when landed.

Inexpensive, got an exit row aisle aeat with no middle passenger, bought a great breakfast sandwich, flight comfortable & arrived ahead of schedule.

I wouldn't say I liked being forced to check my small roller bag at the gate; too many people had bags and were in a higher boarding group.

715PM departure was 2.5 hours late. Received hotel & food voucher but after we already booked a room. Entire team just seemed like they were 2-3 steps behind in execution, and notifcations.

the seat has a problem. the back had a hole.

My flight was delayed so bad i missed u it so i just said never mind

Delayed 2 hours while stuck on the aircraft. If the luggage was properly loaded the first time we probably wouldn’t have been delayed at all

Onboard staff was courteous, helpful, responsive and friendly. The boarding process was disorganized, poorly communicated, and disheveled. Gate agents were yelling instead of using the PA system, didn’t communicate the timing delay of our flight, and created an atmosphere of chaos rather than order and communication. As far as I know, there was no reason for their. I would hate to see how it operated under extreme conditions. I’ve never seen United Airlines operations in such a state.

The flight did not have its customary snacks during the flight. Apparently they were never loaded on the plane.

Like: departed and arrived on time. Unlike: Food options for purchase allways bad, 1 of 2 of the crew members not very friendly at all. Seats and leg room aweful. At this point I am thinking on switching to AA.

Over 5 hour delay with minimal updates or ability to standby for alternative flights. During boarding and 1 hr+ wait for takeoff, seats were drenched w water from air conditioning condensation and always leftover crumbs on carpet and seats

After arriving in Chicago, we were taxiing for 1.5 hours with infrequent and untruthful updates about the amount of time it would take to arrive at the gate. Minimally, the team could have provided timing expectations that were more truthful, especially one their original expectations were not met.

United didn’t even try to hold the flight for me. They knew I had a tight connection and when I arrived at the gate less than 10 mins after final boarding the flight had already gone. The gate agent wasn’t even notified that I was on my way. She was told I wasn’t at the airport

We boarded and buckled and then deplaned due to no pilot. Had to wait over 3 hours for a new pilot. Not weather related, just poor management.

Did not know that they didn’t have screens for entertainment. I didn’t have headphones so I couldn’t watch anything on my phone.

Disorganized boarding. Mandatory to gate check bags. Curt flight staff. No space for cabin bag, even when I was in first class.

Patrons with larger bags were asked to check the bags when boarding. Seems like the most effective, and least costly way, way to successfully use the cramped space.

They cancelled our flight two times after rebooking us for a later flight. We never got on the plane. We found another solution by driving.

Mostly great. Only issue was with the WiFi. Halfway through the flight it was spotty and I was unable to work as I planned. This impacted my work products as I am traveling for business and it was an unexpected hindrance which was inconvenient. Flight here was amazing. For a 5 hour flight something more than a Biscoff would be nice but I’m just swinging at windmills I guess…

Delayed boarding because a flight attendant couldn't find the gate...sat on the plane for over an hour at the gate because AA couldn't get one of the planes behind us to move

The seats were extremely cramped, with very little legroom or personal space. There was no room left in the overhead bins for a backpack, and the space under the seat in front was so limited that I could barely fit my bag underneath. Overall, the seating arrangement felt very uncomfortable and overcrowded.

As always, most AA flights that we fly are almost ALWAYS delayed and that too multiple times. Very frustrating

The small flights with Valet Luggage has a poor service

Overall a good experience, however Wifi was not working on the flight.

I know Frontier is a “no-frills” airline. I understand the concept. However, I jumped on some tickets for our family vacation, expecting to play a bit of a game to figure out the family bags and not over spend. In the end, I got the short end of this deal by far. 1. I did not expect them to charge the baggage fee for each direction. It makes the fee look high-ish at a glance, but reasonable. Then when you get to checkout and realize you have to pay it twice to come home with your luggage, it becomes ridiculous. 2. The low checked bag weight limit. I am used to packing a 50lb bag with my preferred airline. Frontier’s artificially low 40lb limit more quickly triggers the extra weight fee, which almost DOUBLES the price of the bag if you go over ($79 for the bag/$75 for the next 10 lbs) 3. The fee for a carry-on bag is the same as a checked bag but with a lower size and weight limit. Make it make sense! 4. The seats are terrible. My 2.5 hour flight almost had me losing my mind. I’m 6’3” and my femurs barely fit in the space provided. My knees had to wiggle just right to jam into the crack next to the armrest of the seat in front of me. The cushioning was thin and inadequate. I am tall but I’m not a freak. These seats are unacceptable. 5. I overheard the woman next to me speaking with the gate agent about being charged a $25 fee for not checking in online - she checked in at the airport counter when she arrived. That’s ridiculous. She was old and in a wheelchair. She had a paper boarding pass, and was obviously not tech savvy. She should not be punished for that. 6. They do not have good placement in the terminals. It was always out on the end or down on a subfloor, and we had to walk out on the tarmac almost every time. In Denver. Their home airport! 7. Every time I loaded a new page on the website while buying my tickets or my bags, it was constantly trying to upsell me on some esoteric bundle. Like, a pop-up every time. Very annoying. 8. No screens in the boarding area (at least where we were) to confirm you’re in the right place. Just static gate number signs. I am sure these are standard practices for Frontier, and I should have read more about them before I purchased tickets, but as a result of this single round trip, I do not plan to ever use this cut-rate airline again. I would rather pay the normal amount for a ticket and be treated like a customer instead of a mark.

More inflight connection. And leg space is horrible. And the paying for baggage I'd ridiculous!!!

Frontier Airlines was AWFUL. I was an hour early for my flight and the lady refused to check me in. I had to purchase a whole new ticket with a different airline.

I missed a flight because of a delay. I had to buy a new ticket through Southwest.

Bag should not be so much money. This is how Frontier takes advantage of customers

Frontier is definitely a good option for people traveling light or on a budget - just remember to bring your own entertainment and your own headphones if you need them.

Never offer anything to drink ☹️ Flight delayed gate moved poor communication

It’s a cheap airline. I wish they had better seats.

Seats are cramped and very uncomfortable. You have to pay for everything and it is too expensive.

The experience was terrible. The flight boarded late, then after leaving the gate the plane had had to return to the gate for fuel. After 2 hours on the plane, the flight was canceled. The reasons given for the cancelation didn't sound truthful. and different reasons were given. My 15 year old daughter was flying alone on this flight. When they all disembarked the plane she kept asking the crew what she was supposed to do. No one even gave her the courtesy of a response. No one. It took another 4.75 hrs to be out of customs and baggage. She was re-booked the following day. That flight departed 2 hours late. After all of that, they offered a measly $100 flight voucher with an expiry date of 3 months! All in all a terrible experience. We won't be using Frontier again in the future.

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

Complete your trip to St. Charles with a hotel stay or car rental