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St. Charles

$54+ 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 2/24. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — STL
Mar 2 — Mar 91
Mon 3/2
Mon 3/9
1 adult, Economy
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Cheapflights Tip: The best prices from Washington, D.C. to St. Charles are usually found in August or October, booked 56 days in advance, depart on a Saturday or Tuesday and return on a Friday

Cheap 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 January 31, 2026.

This Kiwi.com deal was found by Cheapflights users on 1/30. 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.
Fri 2/208:39 pm
BWI
-
STL
1 stop11h 12m
Frontier
Mon 2/238:22 pm
STL
-
BWI
1 stop19h 51m
Frontier
Deal found 1/30$124
This Kiwi.com deal was found by Cheapflights users on 1/30. 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.
Tue 2/175:54 pm
BWI
-
STL
1 stop13h 57m
Frontier
Mon 2/238:22 pm
STL
-
BWI
1 stop19h 51m
Frontier
Deal found 1/30$129
This Kiwi.com deal was found by Cheapflights users on 1/30. 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.
Wed 3/411:30 am
BWI
-
STL
1 stop11h 57m
Multiple Airlines
Wed 3/1811:32 am
STL
-
BWI
1 stop12h 09m
Multiple Airlines
Deal found 1/30$135
This Kiwi.com deal was found by Cheapflights users on 1/30. 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.
Fri 2/276:08 pm
BWI
-
STL
1 stop13h 43m
Frontier
Fri 3/61:09 pm
STL
-
BWI
1 stop10h 22m
Frontier
Deal found 1/30$139
This Kiwi.com deal was found by Cheapflights users on 1/30. 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.
Mon 3/165:31 am
BWI
-
STL
1 stop9h 03m
Frontier
Wed 3/1811:32 am
STL
-
BWI
1 stop12h 09m
Frontier
Deal found 1/30$144
This CheapOair deal was found by Cheapflights users on 1/29. 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.
Mon 2/232:58 pm
BWI
-
STL
1 stop10h 01m
Frontier
Tue 2/243:49 pm
STL
-
BWI
1 stop26h 41m
Frontier
Deal found 1/29$149
This Kiwi.com deal was found by Cheapflights users on 1/29. 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.
Sun 2/226:00 am
BWI
-
STL
1 stop25h 51m
Frontier
Tue 2/243:49 pm
STL
-
BWI
1 stop26h 41m
Frontier
Deal found 1/29$152
This Kiwi.com deal was found by Cheapflights users on 1/30. 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.
Sat 2/74:44 pm
BWI
-
STL
1 stop7h 49m
Multiple Airlines
Mon 2/98:22 pm
STL
-
BWI
1 stop19h 51m
Multiple Airlines
Deal found 1/30$155
This Kiwi.com deal was found by Cheapflights users on 1/30. 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.
Tue 2/1711:30 am
BWI
-
STL
2 stops20h 21m
Multiple Airlines
Mon 2/238:22 pm
STL
-
BWI
1 stop19h 51m
Multiple Airlines
Deal found 1/30$156
This Kiwi.com deal was found by Cheapflights users on 1/29. 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 3/55:53 pm
BWI
-
STL
2 stops14h 09m
Frontier
Wed 3/1111:32 am
STL
-
BWI
1 stop12h 09m
Frontier
Deal found 1/29$158
This Kiwi.com deal was found by Cheapflights users on 1/30. 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.
Wed 4/13:19 pm
BWI
-
STL
1 stop20h 11m
Frontier
Sun 4/1211:21 am
STL
-
BWI
1 stop22h 24m
Frontier
Deal found 1/30$161
This Kiwi.com deal was found by Cheapflights users on 1/29. 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.
Sun 5/39:51 am
IAD
-
STL
1 stop21h 59m
Frontier
Wed 5/64:55 pm
STL
-
IAD
1 stop13h 32m
Frontier
Deal found 1/29$254

Find 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 January 31, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$124
(Kiwi.com)

One-way from

$54
(Trip.com)

Popular in

January

Cheapest in

August

Average price

$468
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. 16% potential increase in price ($66 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($13 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
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 January 31, 2026.
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

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Wed 3/4

6:45 pm-8:23 pm

Nonstop2h 38m

Lambert-St Louis

Wed 3/18

7:00 pm-11:59 pm

1 stop3h 59m

$255

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 2/21

4:25 pm-9:50 pm

1 stop6h 25m

Lambert-St Louis

Tue 2/24

10:15 am-6:00 pm

2 stops6h 45m

$258

BaltimoreSt. Louis

BWI - STL

BWISTL

Baltimore/Washington

Sun 3/1

6:00 am-6:51 am

1 stop25h 51m

Lambert-St Louis

Sun 3/8

7:52 am-8:58 pm

1 stop12h 06m

$264

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Wed 3/4

6:00 am-11:02 am

1 stop6h 02m

Lambert-St Louis

Wed 3/18

6:59 pm-12:27 am

1 stop4h 28m

$265

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Fri 4/17

6:00 pm-7:12 pm

1 stop26h 12m

Lambert-St Louis

Mon 4/20

8:12 pm-9:59 pm

1 stop24h 47m

$266

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Sat 2/21

3:40 pm-8:00 pm

1 stop5h 20m

Lambert-St Louis

Mon 2/23

8:25 am-11:20 am

Nonstop1h 55m

$272

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Wed 3/4

8:40 am-10:13 am

Nonstop2h 33m

Lambert-St Louis

Sat 3/7

7:41 am-4:09 pm

1 stop7h 28m

$274

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Thu 4/23

2:45 pm-4:05 pm

Nonstop2h 20m

Lambert-St Louis

Tue 4/28

3:40 pm-6:40 pm

Nonstop2h 00m

$274

Washington, D.C.St. Louis

IAD - STL

IADSTL

Washington, D.C. Dulles Intl

Fri 4/3

8:30 pm-7:51 am

1 stop12h 21m

Lambert-St Louis

Mon 4/6

4:54 pm-5:31 pm

1 stop23h 37m

$275

Washington, D.C.St. Louis

DCA - STL

DCASTL

Washington, D.C. Reagan-National

Thu 4/2

7:30 am-9:06 am

Nonstop2h 36m

Lambert-St Louis

Tue 4/7

6:00 am-9:15 am

Nonstop2h 15m

$276

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/31

Showing 1-10 of 60 results
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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 January 30, 2026.

Booking 56 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 $229). 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 January 31, 2026.

It’s optimal to fly from Washington, D.C. to St. Charles in the evening. By choosing this option you can save up to 26% 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 January 24, 2026.

Travelers seeking maximum savings on their Washington, D.C. to St. Charles flight should consider departing on Friday 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.

Weekly flight availability from Washington, D.C. to St. Charles

Explore weekly flight availability from Washington, D.C. to St. Charles. Discover flights operating on different days of the week, giving you the flexibility to choose a travel day that best fits your plans. Compare info to find the most convenient option for your journey. Data last updated January 31, 2026.

The most flights from WAS to CH5 are scheduled on a Friday (16 on average). You will have fewer flight options on Wednesday, which is when the least amount of flights are scheduled (10 on average).

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 January 31, 2026.
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
4,267 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Overall

8.0

Boarding

8.1

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Southwest
8.0
Very good
4,267 reviews
Southwest
8.0
Very good
4,267 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Overall

8.0

Boarding

8.1

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Delta
7.9
Good
8,130 reviews
Southwest
8.0
Very good
4,267 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Overall

8.0

Boarding

8.1

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
United Airlines
7.4
Good
9,219 reviews
Southwest
8.0
Very good
4,267 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Overall

8.0

Boarding

8.1

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
American Airlines
7.2
Good
11,213 reviews
Southwest
8.0
Very good
4,267 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Overall

8.0

Boarding

8.1

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Frontier
5.7
Fair
3,054 reviews
Southwest
8.0
Very good
4,267 reviews

Crew

8.6

Food

7.0

Entertainment

7.5

Overall

8.0

Boarding

8.1

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am

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 $255, United Airlines can have you in St. Charles from Washington, D.C. in 2h 38m. The distance between Washington, D.C. and St. Charles is about 694 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 $60 on Frontier. Other airlines that offer cheap prices include American Airlines from $98 and Southwest from $98 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 (76%), United Airlines (76%) or Avianca (64%) 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 $516, our data shows the cheapest flight currently is $113. When looking at the most popular route, (Washington, D.C. Dulles Intl - Lambert-St Louis), you can expect to pay $172 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 $229). 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

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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 January 31, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$78Average$197FlexibilityNo cancel feeOn-time62%
DeltaCheapest$124Average$288FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$167Average$392FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$185Average$358FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$233Average$455FlexibilityNo cancel feeOn-time69%

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