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St. Charles

$68+ Cheap flights from Boston (BOS) 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 1/10. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — STL
nov. 29 — déc. 61
sam. 11/29
sam. 12/6
1 adult, Economy
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Cheapflights Tip: The best prices from Boston Logan Intl to St. Charles are usually found in August or September, booked 25 days in advance, depart on a Wednesday or Thursday and return on a Friday

Cheap flight deals from Boston to St. Charles

Keep the following information in mind while searching for Boston to St. Charles flight deals. Data was last updated octobre 30, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$328
(American Airlines)

One-way from

$68
(Trip.com)

Popular in

October

Cheapest in

August

Average price

$512
Provider with most accurate pricing for Boston Logan Intl-Lambert-St Louis flight deals.
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Provider most trusted by Cheapflights users for Boston Logan Intl-Lambert-St Louis flights.
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From Boston Logan Intl to St. Charles
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One-way flight from Boston Logan Intl to St. Charles
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Highest demand for flights based on searches. 1% potential increase in price ($7 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in October 2025
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Find flight deals from Boston to St. Charles

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

This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mer. 12/316:36 amBOS - STL
1 stop10h 47mAmerican Airlines
sam. 1/310:01 amSTL - BOS
Nonstop2h 42mAmerican Airlines
Deal found 10/30$329
This Priceline 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
dim. 11/236:00 amBOS - STL
1 stop9h 29mFrontier
mar. 11/253:14 pmSTL - BOS
1 stop8h 30mFrontier
Deal found 10/30$330
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.
jeu. 12/48:11 pmBOS - STL
1 stop13h 48mMultiple Airlines
ven. 12/1210:42 amSTL - BOS
2 stops12h 14mMultiple Airlines
Deal found 10/28$332
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.
lun. 12/811:08 amBOS - STL
1 stop12h 25mMultiple Airlines
sam. 12/137:43 pmSTL - BOS
2 stops13h 39mMultiple Airlines
Deal found 10/28$333
This Mytrip 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jeu. 11/136:16 amBOS - STL
1 stop12h 41mSpirit Airlines
jeu. 11/2010:53 amSTL - BOS
3 stops28h 57mSpirit Airlines
Deal found 10/30$334
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.
ven. 12/511:08 amBOS - STL
1 stop12h 25mMultiple Airlines
sam. 12/137:43 pmSTL - BOS
2 stops13h 39mMultiple Airlines
Deal found 10/28$335
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.
lun. 11/109:55 amBOS - STL
2 stops24h 12mFrontier
jeu. 11/132:12 pmSTL - BOS
1 stop17h 16mFrontier
Deal found 10/29$337
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.
lun. 12/296:00 amBOS - STL
1 stop28h 40mFrontier
sam. 1/37:43 pmSTL - BOS
2 stops34h 40mFrontier
Deal found 10/29$338
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.
mer. 11/126:16 amBOS - STL
2 stops28h 56mMultiple Airlines
sam. 11/154:33 pmSTL - BOS
1 stop18h 31mMultiple Airlines
Deal found 10/29$340
This Mytrip 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
mer. 11/196:26 pmBOS - STL
3 stops25h 10mMultiple Airlines
sam. 11/229:52 amSTL - BOS
1 stop13h 01mMultiple Airlines
Deal found 10/28$342
This Kiwi.com deal was found by Cheapflights users on 10/27. 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.
mer. 11/269:54 pmBOS - STL
1 stop17h 35mMultiple Airlines
mer. 12/37:43 pmSTL - BOS
2 stops13h 39mMultiple Airlines
Deal found 10/27$343

Cheapflights Fare Finder

 
Customize your flight search to find flights from Boston 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 octobre 30, 2025.
Use the filters below to find and compare flights from Boston to St. Charles that are best for you.

Fly from

Boston

Fly to

St. Charles

Route

Depart

Return

Price

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

mer. 12/17

7:20 am-9:30 am

Nonstop3h 10m

Lambert-St Louis

mer. 1/7

5:55 pm-9:25 pm

Nonstop2h 30m

$349

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

jeu. 12/4

7:20 am-9:30 am

Nonstop3h 10m

Lambert-St Louis

lun. 12/8

8:15 am-11:45 am

Nonstop2h 30m

$349

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

jeu. 11/27

12:15 pm-6:35 pm

1 stop7h 20m

Lambert-St Louis

lun. 12/1

7:02 pm-1:26 am

1 stop5h 24m

$384

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

ven. 12/19

5:29 am-9:50 am

1 stop5h 21m

Lambert-St Louis

jeu. 12/25

10:04 am-5:56 pm

1 stop6h 52m

$384

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

jeu. 12/4

6:00 pm-10:10 pm

1 stop5h 10m

Lambert-St Louis

dim. 12/14

8:10 pm-11:40 pm

Nonstop2h 30m

$405

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

ven. 12/12

5:13 pm-11:42 pm

1 stop7h 29m

Lambert-St Louis

lun. 12/15

5:12 pm-11:24 pm

1 stop5h 12m

$406

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

mar. 12/30

5:40 am-12:21 pm

1 stop7h 41m

Lambert-St Louis

sam. 1/3

6:25 pm-11:57 pm

1 stop4h 32m

$415

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

lun. 11/24

5:40 am-1:00 pm

1 stop8h 20m

Lambert-St Louis

ven. 11/28

6:40 am-11:55 am

1 stop4h 15m

$422

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

mer. 11/19

5:15 pm-7:30 pm

Nonstop3h 15m

Lambert-St Louis

sam. 11/22

8:40 pm-12:10 am

Nonstop2h 30m

$424

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

sam. 1/10

10:30 am-7:27 pm

2 stops9h 57m

Lambert-St Louis

mer. 1/14

6:30 am-2:17 pm

2 stops6h 47m

$430

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/28

Showing 1-10 of 22 results
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Best time to book a flight from Boston to St. Charles

Have a flexible travel schedule? Discover the best time to fly to St. Charles from Boston 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 Boston to St. Charles

How far ahead should I book a flight from Boston to St. Charles?

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

To ensure you get the cheapest price possible for a flight from Boston to St. Charles, you should look to book at least 25 days in advance of your intended travel date. The price of your flight may increase if you delay and leave booking until a week or so before departure.

What is the cheapest month to book a flight from Boston to St. Charles?

Currently, December is the cheapest month in which you can book a flight from Boston to St. Charles (average of $107). Flying from Boston to St. Charles in July is currently the most expensive (average of $300). 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 BOS to CH5?

Find hourly flight availability from Boston 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 octobre 30, 2025.

It’s optimal to fly from Boston to St. Charles in the evening. By choosing this option you can save up to 21% on the cost of your flight, compared to a flight in the morning.

What is the cheapest day to fly from Boston to St. Charles?

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

Travelers seeking maximum savings on their Boston to St. Charles flight should consider departing on Saturday at noon when fares are most often at their lowest. Monday 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 octobre 30, 2025.
Peruse reviews from past customers who have flown with Southwest, Delta, and American Airlines from Boston to St. Charles to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,243 reviews

Food

7.0

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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

Food

7.0

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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

Food

7.0

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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

Food

7.0

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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
Spirit Airlines
6.3
Okay
8,116 reviews
Southwest
8.0
Very good
4,243 reviews

Food

7.0

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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

Food

7.0

Comfort

8.0

Entertainment

7.5

Crew

8.6

Overall

8.0

Boarding

8.1

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 Boston to St. Charles. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from Boston to St. Charles?

    Boston Logan Intl (BOS) is the airport you will fly out of if you book a flight from Boston to St. Charles. You should not have trouble finding flights to St. Charles from Logan Intl; the airport handles an average of 1 outbound flight to St. Charles per day. You should also have plenty of airline options to choose from since 6 airlines have flights from the Boston airport to St. Charles. It is only a 2.6 mi journey to Logan Intl (BOS) from Boston’s city center.

  • How popular is this Boston to St. Charles flight route?

    The Boston Logan Intl to St. Charles flight path was viewed by 51 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • How long is the flight from Boston to St. Charles?

    There are many flights that can get you from Boston to St. Charles in 3h 10m. Fly via Southwest or Delta to get the fastest option. There are 1043 mi between Boston and St. Charles. This flight may include one or multiple stops.

  • What are the most reliable airlines from Boston to St. Charles?

    No one likes to see their flight delayed. When booking a flight from Boston to St. Charles consider choosing Iberia (98%), Envoy Air (86%) or American Airlines (84%) as they are the most reliable in getting you off to your destination on time.

  • What are the cheapest flights from Boston to St. Charles?

    Looking at all options, your cheapest flight can be booked for $118. While the most popular route (Boston Logan Intl - Lambert-St Louis) can be booked for $167 on average, our data indicates $355 when flying from Boston to St. Charles.

  • Can I find deals for flights from Boston to St. Charles that include hotel bookings?

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

  • How can I find direct flights from Boston to St. Charles?

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

  • Can I find deals for business class flights from Boston to St. Charles?

    Yes. Cheapflights offers flight deals from Boston 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 Boston to St. Charles?

    Currently, December is the cheapest month in which you can book a flight from Boston to St. Charles (average of $107). Flying from Boston to St. Charles in July is currently the most expensive (average of $300). 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

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Top 6 airlines flying from Boston to St. Charles

Discover the top 6 airlines that operate flights from Boston 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 octobre 30, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$83Average$186FlexibilityNo cancel feeOn-time65%
FrontierCheapest$110Average$208FlexibilityNo cancel feeOn-time62%
DeltaCheapest$216Average$294FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$261Average$406FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$297Average$511FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$320Average$466FlexibilityNo cancel feeOn-time63%

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