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St. Charles

$93+ 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 10/15. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — STL
Oct 15 — Oct 221
Wed 10/15
Wed 10/22
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 January, booked 25 days in advance, depart on a Wednesday or Thursday and return on a Thursday

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 September 15, 2025.

Round-trip from

$273
(Kiwi.com)

One-way from

$93
(Kiwi.com)

Popular in

April

Cheapest in

August

Average price

$421
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. 7% potential increase in price ($35 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 September 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 September 15, 2025.

This Kiwi.com deal was found by Cheapflights users on 9/14. 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 10/16:10 amBOS - STL
1 stop28h 30mMultiple Airlines
Thu 10/24:00 pmSTL - BOS
2 stops18h 13mMultiple Airlines
Deal found 9/14$271
This Kiwi.com deal was found by Cheapflights users on 9/15. 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 10/178:24 pmBOS - STL
1 stop22h 46mMultiple Airlines
Mon 10/208:21 pmSTL - BOS
2 stops15h 59mMultiple Airlines
Deal found 9/15$273
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 10/99:50 amBOS - STL
1 stop25h 47mMultiple Airlines
Sat 10/117:15 pmSTL - BOS
1 stop15h 11mMultiple Airlines
Deal found 9/14$274
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 10/248:24 pmBOS - STL
1 stop22h 46mSpirit Airlines
Sun 10/2610:57 amSTL - BOS
1 stop12h 02mSpirit Airlines
Deal found 9/14$275
This American Airlines deal was found by Cheapflights users on 9/14. 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.
Sat 10/188:00 amBOS - STL
1 stop9h 04mAmerican Airlines
Mon 10/209:35 amSTL - BOS
Nonstop2h 37mAmerican Airlines
Deal found 9/14$276
This Kiwi.com deal was found by Cheapflights users on 9/13. 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 9/288:47 amBOS - STL
2 stops31h 17mMultiple Airlines
Thu 10/210:35 amSTL - BOS
1 stop12h 22mMultiple Airlines
Deal found 9/13$277
This Orbitz deal was found by Cheapflights users on 9/13. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/249:18 amBOS - STL
1 stop9h 29mMultiple Airlines
Sun 10/2610:57 amSTL - BOS
1 stop12h 02mMultiple Airlines
Deal found 9/13$278
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 10/312:59 pmBOS - STL
2 stops21h 07mMultiple Airlines
Sun 10/510:57 amSTL - BOS
1 stop23h 29mMultiple Airlines
Deal found 9/14$279
This American Airlines deal was found by Cheapflights users on 9/14. 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.
Tue 12/26:00 amBOS - STL
1 stop5h 18mAmerican Airlines
Sat 12/61:59 pmSTL - BOS
1 stop9h 00mAmerican Airlines
Deal found 9/14$280
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 12/811:13 amBOS - STL
1 stop12h 33mMultiple Airlines
Thu 12/1112:20 pmSTL - BOS
1 stop11h 20mMultiple Airlines
Deal found 9/14$282
This Kiwi.com deal was found by Cheapflights users on 9/15. 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 10/43:00 pmBOS - STL
1 stop20h 02mMultiple Airlines
Sun 10/54:00 pmSTL - BOS
2 stops18h 26mMultiple Airlines
Deal found 9/15$283
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 10/43:00 pmBOS - STL
1 stop20h 02mMultiple Airlines
Mon 10/67:55 pmSTL - BOS
2 stops16h 25mMultiple Airlines
Deal found 9/14$284

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 September 15, 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

Fri 10/24

8:47 pm-10:49 am

1 stop15h 02m

Lambert-St Louis

Mon 10/27

5:24 pm-4:10 pm

1 stop21h 46m

$333

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Wed 12/3

10:20 am-12:25 pm

Nonstop3h 05m

Lambert-St Louis

Sat 12/6

8:25 am-11:55 am

Nonstop2h 30m

$333

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Tue 12/2

5:15 pm-7:30 pm

Nonstop3h 15m

Lambert-St Louis

Mon 12/8

12:45 pm-9:05 pm

2 stops7h 20m

$348

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Sat 12/6

7:25 am-9:40 am

Nonstop3h 15m

Lambert-St Louis

Mon 12/8

1:50 pm-5:20 pm

Nonstop2h 30m

$349

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Tue 10/21

5:30 am-11:45 am

1 stop7h 15m

Lambert-St Louis

Fri 10/24

8:10 pm-11:40 pm

Nonstop2h 30m

$370

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Thu 10/9

5:30 am-12:28 pm

2 stops7h 58m

Lambert-St Louis

Mon 10/13

12:25 pm-9:45 pm

1 stop8h 20m

$371

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Sun 12/7

1:30 pm-3:35 pm

Nonstop3h 05m

Lambert-St Louis

Tue 12/9

6:10 pm-9:40 pm

Nonstop2h 30m

$379

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Wed 10/22

5:40 pm-7:50 pm

Nonstop3h 10m

Lambert-St Louis

Sun 10/26

8:10 pm-11:40 pm

Nonstop2h 30m

$379

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Mon 12/8

5:45 am-12:35 pm

2 stops7h 50m

Lambert-St Louis

Thu 12/11

10:15 am-7:10 pm

2 stops7h 55m

$379

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Thu 10/16

11:02 am-3:44 pm

1 stop5h 42m

Lambert-St Louis

Sun 10/19

5:00 am-11:02 am

1 stop5h 02m

$384

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/14

Showing 1-10 of 20 results
1
2

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 September 12, 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, August is the cheapest month in which you can book a flight from Boston to St. Charles (average of $311). Flying from Boston to St. Charles in March is currently the most expensive (average of $356). 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 September 15, 2025.

When flying from Boston to St. Charles, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 Wednesday at noon when fares are most often at their lowest. Sunday evenings flights should be avoided if possible as fares are typically the most expensive at this time.

Weekly flight availability from Boston to St. Charles

Explore weekly flight availability from Boston 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 September 15, 2025.

The most flights from BOS to CH5 are scheduled on a Monday (6 on average). You will have fewer flight options on Tuesday, which is when the least amount of flights are scheduled (3 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 September 15, 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
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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
4,242 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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
8.0
Very good
7,954 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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
10,000 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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
8,015 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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
3,172 reviews
Southwest
8.0
Very good
4,242 reviews

Food

7.0

Boarding

8.1

Comfort

8.0

Crew

8.6

Overall

8.0

Entertainment

7.5

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 4 outbound flights 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 45 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 05m. Fly via United Airlines or Southwest 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 cheapest airlines to fly from Boston to St. Charles one-way?

    The cheapest airlines for a one-way flight from Boston to St. Charles are Spirit Airlines ($93), United Airlines ($149), and Delta ($153).

  • 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%), American Airlines (85%) or Envoy Air (85%) 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 $108. While the most popular route (Boston Logan Intl - Lambert-St Louis) can be booked for $205 on average, our data indicates $329 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, August is the cheapest month in which you can book a flight from Boston to St. Charles (average of $311). Flying from Boston to St. Charles in March is currently the most expensive (average of $356). 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 September 15, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$83Average$186FlexibilityNo cancel feeOn-time65%
FrontierCheapest$113Average$213FlexibilityNo cancel feeOn-time62%
DeltaCheapest$216Average$294FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$257Average$412FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$297Average$512FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$323Average$462FlexibilityNo cancel feeOn-time63%

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