HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
St. Charles

$55+ Cheap flights from Washington, D.C. (WAS) to St. Charles, MO

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/4. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — STL
Nov 29 — Dec 61
Sat 11/29
Sat 12/6
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Washington, D.C. to St. Charles with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheapflights Tip: The best prices from Washington, D.C. to St. Charles are usually found in August or September, booked 66 days in advance, depart on a Tuesday or Wednesday and return on a Friday

Find flight deals from Washington, D.C. to St. Charles

Cheapest flights from Washington, D.C. to St. Charles
Explore the most affordable flight options available from Washington, D.C. to St. Charles. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 30, 2025.

This Frontier deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/55:45 amBWI - STL
1 stop5h 02mFrontier
Thu 12/1112:04 pmSTL - BWI
1 stop11h 20mFrontier
Deal found 10/30$144
This CheapOair deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/810:16 amBWI - STL
1 stop6h 22mFrontier
Thu 11/132:12 pmSTL - BWI
1 stop17h 22mFrontier
Deal found 10/30$150
This Frontier deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/79:43 pmBWI - STL
1 stop12h 16mFrontier
Thu 12/1112:04 pmSTL - BWI
1 stop11h 20mFrontier
Deal found 10/28$163
This Flightnetwork deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Flightnetwork is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/68:37 amBWI - STL
1 stop14h 56mFrontier
Mon 12/89:54 amSTL - BWI
1 stop9h 22mFrontier
Deal found 10/29$170
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/134:15 pmBWI - STL
1 stop24h 46mFrontier
Mon 11/177:45 pmSTL - BWI
2 stops21h 44mFrontier
Deal found 10/29$176
This CheapOair deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/311:16 amBWI - STL
1 stop12h 17mFrontier
Sun 12/73:30 pmSTL - BWI
1 stop15h 12mFrontier
Deal found 10/29$183
This Kiwi.com deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/810:40 amBWI - STL
1 stop12h 53mMultiple Airlines
Fri 12/123:30 pmSTL - BWI
1 stop7h 53mMultiple Airlines
Deal found 10/28$188
This Frontier deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/45:45 amBWI - STL
1 stop6h 22mFrontier
Fri 12/129:54 amSTL - BWI
1 stop9h 22mFrontier
Deal found 10/28$189
This CheapOair deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/208:45 pmBWI - STL
1 stop28h 12mFrontier
Mon 11/244:13 pmSTL - BWI
1 stop27h 37mFrontier
Deal found 10/30$190
This Kiwi.com deal was found by Cheapflights users on 10/28. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/65:52 pmBWI - STL
2 stops16h 55mFrontier
Thu 12/1112:04 pmSTL - BWI
1 stop11h 20mFrontier
Deal found 10/28$191
This Kiwi.com deal was found by Cheapflights users on 10/30. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/134:55 pmBWI - STL
1 stop24h 06mMultiple Airlines
Mon 11/177:45 pmSTL - BWI
2 stops16h 10mMultiple Airlines
Deal found 10/30$192
This Kiwi.com deal was found by Cheapflights users on 10/29. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/174:30 pmBWI - STL
2 stops41h 37mFrontier
Wed 12/33:30 pmSTL - BWI
1 stop15h 12mFrontier
Deal found 10/29$195

Cheap flight deals from Washington, D.C. to St. Charles

Keep the following information in mind while searching for Washington, D.C. to St. Charles flight deals. Data was last updated October 30, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$144
(Frontier)

One-way from

$55
(Frontier)

Popular in

October

Cheapest in

August

Average price

$407
Provider with most accurate pricing for Washington, D.C. (WAS)-Lambert-St Louis flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. (WAS)-Lambert-St Louis flights.
Search Deals
From Washington, D.C. (WAS) to St. Charles
Search Deals
One-way flight from Washington, D.C. (WAS) to St. Charles
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($14 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($8 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in October 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Washington, D.C. to St. Charles that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 30, 2025.
Use the filters below to find and compare flights from Washington, D.C. to St. Charles that are best for you.

Fly from

Washington, D.C.

Fly to

St. Charles

Route

Depart

Return

Price

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Thu 11/20

8:45 pm-11:57 pm

1 stop28h 12m

Lambert-St Louis

Mon 11/24

4:13 pm-8:50 pm

1 stop27h 37m

$190

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Thu 11/20

4:25 pm-11:57 pm

1 stop8h 32m

Lambert-St Louis

Sun 11/23

4:13 pm-8:23 am

1 stop15h 10m

$218

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Thu 11/20

6:55 am-2:29 pm

1 stop8h 34m

Lambert-St Louis

Sun 11/23

3:14 pm-11:59 pm

1 stop7h 45m

$230

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Fri 12/5

3:50 pm-9:35 pm

1 stop6h 45m

Lambert-St Louis

Sat 12/6

6:25 am-1:55 pm

2 stops6h 30m

$234

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Thu 11/20

6:55 am-2:29 pm

1 stop8h 34m

Lambert-St Louis

Sun 11/23

11:08 am-11:59 pm

2 stops35h 51m

$237

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Thu 11/20

8:00 am-6:58 pm

1 stop11h 58m

Lambert-St Louis

Sun 11/23

7:57 pm-1:03 pm

1 stop16h 06m

$242

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Wed 12/24

2:45 pm-4:05 pm

Nonstop2h 20m

Lambert-St Louis

Wed 12/31

1:10 pm-4:10 pm

Nonstop2h 00m

$263

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Thu 1/8

5:30 pm-7:00 pm

Nonstop2h 30m

Lambert-St Louis

Mon 1/12

12:05 pm-7:45 pm

1 stop6h 40m

$267

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Wed 1/7

5:30 pm-7:00 pm

Nonstop2h 30m

Lambert-St Louis

Sun 1/11

12:05 pm-6:30 pm

1 stop5h 25m

$267

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 11/22

6:45 pm-8:10 pm

Nonstop2h 25m

Lambert-St Louis

Mon 11/24

7:55 am-12:50 pm

1 stop3h 55m

$267

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/29

Showing 1-10 of 60 results
1
2
3
...
6

Best time to book a flight from Washington, D.C. to St. Charles

Have a flexible travel schedule? Discover the best time to fly to St. Charles from Washington, D.C. with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

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

How far ahead should I book a flight from Washington, D.C. to St. Charles?

Use this chart to determine the optimal time to book a round-trip flight from Washington, D.C. to St. Charles. Price data was last updated on October 24, 2025.

Booking 66 days in advance of your planned departure date is, on average, the best time to get cheap flights from Washington, D.C. to St. Charles. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from Washington, D.C. to St. Charles?

Currently, September is the cheapest month in which you can book a flight from Washington, D.C. to St. Charles (average of $109). Flying from Washington, D.C. to St. Charles in January is currently the most expensive (average of $199). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from WAS to CH5?

Find hourly flight availability from Washington, D.C. to St. Charles. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated October 30, 2025.

It’s optimal to fly from Washington, D.C. to St. Charles in the evening. By choosing this option you can save up to 52% on the cost of your flight, compared to a flight in the afternoon.

What is the cheapest day to fly from Washington, D.C. to St. Charles?

Use this chart to determine the cheapest time to fly round-trip from Washington, D.C. to St. Charles. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their Washington, D.C. to St. Charles flight should consider departing on Tuesday evenings when fares are most often at their lowest. Sunday afternoons flights should be avoided if possible as fares are typically the most expensive at this time.

Reviews of airlines servicing St. Charles

Get insights into the airlines that provide service to St. Charles. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Charles. Reviews last updated October 30, 2025.
Read reviews from past customers who have flown Southwest, Delta, and United Airlines from Washington, D.C. to St. Charles. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,243 reviews
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Delta
7.9
Good
7,998 reviews
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
United Airlines
7.4
Good
8,998 reviews
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
American Airlines
7.2
Good
11,035 reviews
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Frontier
5.8
Fair
3,122 reviews
Southwest
8.0
Very good
4,243 reviews

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

Find useful and relevant information for your journey from Washington, D.C. to St. Charles. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • How long is the flight from Washington, D.C. to St. Charles?

    For as low as $234, Frontier can have you in St. Charles from Washington, D.C. in 6h 45m. The distance between Washington, D.C. and St. Charles is about 736 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the cheapest airlines to fly from Washington, D.C. to St. Charles one-way?

    One-way options have recently been found by users for as low as $81 on Frontier. Other airlines that offer cheap prices include American Airlines from $109 and Southwest from $110 one-way.

  • What are the most popular routes from Washington, D.C. to St. Charles?

    Most travelers choose Washington, D.C. Dulles Intl - Lambert-St Louis, Baltimore/Washington - Lambert-St Louis or Washington, D.C. Reagan-National - Lambert-St Louis when deciding on the best route from Washington, D.C. to St. Charles.

  • What are the most reliable airlines from Washington, D.C. to St. Charles?

    No one likes to see their flight delayed. When booking a flight from Washington, D.C. to St. Charles consider choosing GoJet (84%), Avianca (84%) or United Airlines (84%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Washington, D.C. to St. Charles?

    While on average a flight from Washington, D.C. to St. Charles is generally $350, our data shows the cheapest flight currently is $134. When looking at the most popular route, (Washington, D.C. Dulles Intl - Lambert-St Louis), you can expect to pay $143 for that flight.

  • Can I find deals for flights from Washington, D.C. to St. Charles that include hotel bookings?

    Yes. In addition to deals on Washington, D.C. to St. Charles flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Washington, D.C. to St. Charles?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Washington, D.C. to St. Charles.

  • Can I find deals for business class flights from Washington, D.C. to St. Charles?

    Yes. Cheapflights offers flight deals from Washington, D.C. to St. Charles by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from Washington, D.C. to St. Charles?

    Currently, September is the cheapest month in which you can book a flight from Washington, D.C. to St. Charles (average of $109). Flying from Washington, D.C. to St. Charles in January is currently the most expensive (average of $199). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Top 5 airlines flying from Washington, D.C. to St. Charles

Discover the top 5 airlines that operate flights from Washington, D.C. to St. Charles. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated October 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$112Average$197FlexibilityNo cancel feeOn-time62%
DeltaCheapest$130Average$280FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$174Average$343FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$188Average$347FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$223Average$403FlexibilityNo cancel feeOn-time69%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.