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St. Charles

$147+ 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 5/29. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — STL
Apr 6 — Apr 131
Sun 4/6
Sun 4/13
1 adult, Economy
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Cheapflights Tip: The best prices from Boston Logan Intl to St. Charles are usually found in September or August, booked 63 days in advance, depart on a Tuesday or Wednesday 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 April 1, 2025.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$323
(Mytrip)

One-way from

$147
(United Airlines)

Popular in

March

Cheapest in

September

Average price

$473
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. 6% potential increase in price ($29 potential increase over avg. RT price).
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Cheapest flight prices on average. 1% potential price decrease ($6 potential savings vs. average RT price).
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Average for round-trip flights in April 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 April 1, 2025.

This Mytrip deal was found by Cheapflights users on 3/30. 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.
Wed 4/99:55 amBOS - STL
3 stops33h 46mMultiple Airlines
Mon 4/149:50 amSTL - BOS
3 stops25h 46mMultiple Airlines
Deal found 3/30$319
This Southwest deal was found by Cheapflights users on 3/31. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/207:05 amBOS - STL
Nonstop2h 55mSouthwest
Sat 5/246:45 pmSTL - BOS
Nonstop2h 30mSouthwest
Deal found 3/31$327
This CheapOair deal was found by Cheapflights users on 3/31. 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 6/119:40 amBOS - STL
1 stop15h 09mFrontier
Sun 6/158:44 pmSTL - BOS
1 stop13h 17mFrontier
Deal found 3/31$331
This Delta deal was found by Cheapflights users on 3/31. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/196:50 pmBOS - STL
1 stop5h 46mDelta
Tue 4/226:08 amSTL - BOS
1 stop5h 10mDelta
Deal found 3/31$332
This American Airlines deal was found by Cheapflights users on 3/31. 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 5/206:30 amBOS - STL
Nonstop3h 10mAmerican Airlines
Sat 5/246:20 amSTL - BOS
1 stop6h 36mAmerican Airlines
Deal found 3/31$337
This United deal was found by Cheapflights users on 4/1. 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 United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/55:30 amBOS - STL
2 stops10h 17mUnited Airlines
Tue 5/66:30 amSTL - BOS
1 stop5h 18mUnited Airlines
Deal found 4/1$363
This Mytrip deal was found by Cheapflights users on 3/31. 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.
Tue 4/811:14 amBOS - STL
1 stop7h 38mSpirit Airlines
Thu 4/246:10 pmSTL - BOS
1 stop15h 17mSpirit Airlines
Deal found 3/31$493

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 April 1, 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

Thu 5/8

5:42 pm-8:10 pm

3 stops27h 28m

Lambert-St Louis

Sun 5/11

10:10 am-10:51 pm

3 stops35h 41m

$323

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Tue 5/20

7:05 am-9:00 am

Nonstop2h 55m

Lambert-St Louis

Sat 5/24

6:45 pm-10:15 pm

Nonstop2h 30m

$327

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Wed 6/11

9:40 am-11:49 pm

1 stop15h 09m

Lambert-St Louis

Sun 6/15

8:44 pm-11:01 am

1 stop13h 17m

$331

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Sat 4/19

6:50 pm-11:36 pm

1 stop5h 46m

Lambert-St Louis

Tue 4/22

6:08 am-12:18 pm

1 stop5h 10m

$332

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Tue 5/20

6:30 am-8:40 am

Nonstop3h 10m

Lambert-St Louis

Sat 5/24

6:20 am-1:56 pm

1 stop6h 36m

$337

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Mon 5/5

10:45 am-2:47 pm

1 stop5h 02m

Lambert-St Louis

Wed 5/7

6:30 am-2:19 pm

2 stops6h 49m

$363

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Thu 5/1

11:39 am-11:31 am

1 stop24h 52m

Lambert-St Louis

Sun 5/4

8:00 am-11:04 pm

1 stop14h 04m

$370

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Thu 5/1

5:20 pm-11:59 pm

1 stop31h 39m

Lambert-St Louis

Tue 5/6

6:30 am-11:59 pm

1 stop16h 29m

$503

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Fri 6/27

9:58 am-8:59 am

3 stops24h 01m

Lambert-St Louis

Fri 7/4

4:17 pm-12:11 pm

3 stops18h 54m

$514

BostonSt. Louis

BOS - STL

BOSSTL

Boston Logan Intl

Wed 5/14

10:04 am-9:15 am

3 stops24h 11m

$147

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/1

Showing 1-10 of 18 results
1
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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 March 28, 2025.

To ensure you get the cheapest price possible for a flight from Boston to St. Charles, you should look to book at least 63 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 April 1, 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 June 16, 2024.

Travelers seeking maximum savings on their Boston to St. Charles flight should consider departing on Tuesday 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.

Rainfall in St. Charles by month

Plan your trip to St. Charles by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Charles ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Charles when rainfall is around 2.2 in.

Temperature in St. Charles by month

Plan your trip to St. Charles by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Charles, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

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 April 1, 2025.
Peruse reviews from past customers who have flown with Alaska Airlines, Southwest and Delta from Boston to St. Charles to help guide your decision. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Alaska Airlines
8.0
Very good
9,820 reviews

Comfort

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Entertainment

7.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Alaska Airlines
8.0
Very good
9,820 reviews
Alaska Airlines
8.0
Very good
9,820 reviews

Comfort

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Entertainment

7.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Southwest
8.0
Very good
4,277 reviews
Alaska Airlines
8.0
Very good
9,820 reviews

Comfort

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Entertainment

7.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
Delta
8.0
Very good
7,898 reviews
Alaska Airlines
8.0
Very good
9,820 reviews

Comfort

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Entertainment

7.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
United Airlines
7.4
Good
8,615 reviews
Alaska Airlines
8.0
Very good
9,820 reviews

Comfort

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Entertainment

7.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them
American Airlines
7.2
Good
10,000 reviews
Alaska Airlines
8.0
Very good
9,820 reviews

Comfort

7.9

Crew

8.5

Boarding

8.2

Overall

8.0

Entertainment

7.1

Food

7.1

Reviews

1 / 20
10.0
Excellent

Cheri,Jan 2025

FAT - SEA

Very friendly. I really liked that they had water for us in cartons not plastic. Impressed with Alaska Airlines, First time I had flown them

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 2 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 19 users in the past month. Keep an eye out for changes in search interest prior to high and low season.

  • 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 United Airlines ($147), Southwest ($152), and Spirit Airlines ($154).

  • 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 (100%), Republic Airways (85%) or Qatar Airways (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 $138. While the most popular route (Boston Logan Intl - Lambert-St Louis) can be booked for $200 on average our data indicates $363 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 April 1, 2025.
AirlineCheapestAverageFlexibilityOn-time
Spirit AirlinesCheapest$107Average$167FlexibilityNo cancel feeOn-time65%
FrontierCheapest$113Average$207FlexibilityNo cancel feeOn-time62%
DeltaCheapest$196Average$354FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$257Average$444FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$306Average$517FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$326Average$449FlexibilityNo cancel feeOn-time63%

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