$135+ Cheap flights from Boston (BOS) to St. Charles, MO
This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/7. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — STL
Oct 15 — Oct 221
Round-trip
1 adult, Economy
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Find cheap flights from Boston 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 Boston Logan Intl to St. Charles are usually found in January or May, booked 51 days in advance, depart on a Wednesday or Saturday and return on a Wednesday
Cheap flight deals from Boston to St. Charles
Cheapest
Best
Last-minute
One-way
Cheapest flights from Boston to St. CharlesExplore 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, 2026.
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, 2026.
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.
Tue 10/612:52 pm -
1 stop25h 18m
Mon 10/126:35 pm -
1 stop16h 17m
Deal found 9/14![Frontier logo]()
$337
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/45:20 am -
Nonstop3h 10m
Mon 11/94:40 pm -
2 stops6h 15m
Deal found 9/14![Southwest logo]()
$338
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.
Tue 10/612:52 pm -
1 stop25h 18m
Thu 10/154:30 pm -
1 stop17h 32m
Deal found 9/14![Frontier logo]()
$341
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/57:10 pm -
1 stop5h 32m
Tue 10/610:35 am -
1 stop4h 40m
Deal found 9/14![Delta logo]()
$343
This Trip.com deal was found by Cheapflights users on 9/11. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/1111:47 am -
1 stop12h 26m
Sun 10/184:30 pm -
1 stop17h 32m
Deal found 9/11![Frontier logo]()
$344
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/512:55 pm -
Nonstop3h 00m
Thu 11/57:55 pm -
Nonstop2h 30m
Deal found 9/15![Southwest logo]()
$345
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.
Fri 11/67:00 am -
Nonstop3h 16m
Sat 12/51:10 pm -
Nonstop2h 39m
Deal found 9/14![American Airlines logo]()
$346
This Kiwi.com deal was found by Cheapflights users on 9/12. 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 10/1312:57 pm -
1 stop29h 43m
Thu 10/154:30 pm -
1 stop17h 32m
Deal found 9/12![Frontier logo]()
$348
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/75:35 am -
Nonstop3h 05m
Mon 11/94:40 pm -
2 stops6h 15m
Deal found 9/14![Southwest logo]()
$349
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.
Tue 10/2012:57 pm -
1 stop29h 43m
Sun 10/254:30 pm -
1 stop17h 32m
Deal found 9/15![Frontier logo]()
$350
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1711:47 am -
1 stop12h 26m
Sun 10/184:30 pm -
1 stop17h 32m
Deal found 9/15![Frontier logo]()
$351
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/75:35 am -
2 stops8h 15m
Wed 10/148:30 am -
2 stops6h 35m
Deal found 9/14![Southwest logo]()
$353
Best flights from Boston to St. CharlesDiscover carefully curated flight deals from Boston to St. Charles that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 15, 2026.
Discover carefully curated flight deals from Boston to St. Charles that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated September 15, 2026.
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/245:25 am -
Nonstop3h 00m
Mon 10/262:00 pm -
1 stop7h 05m
Deal found 9/14![Southwest logo]()
$344
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/511:00 am -
1 stop5h 39m
Mon 11/97:18 pm -
1 stop4h 55m
Deal found 9/14![Delta logo]()
$531
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 12/65:45 am -
2 stops7h 37m
Thu 12/106:30 am -
2 stops7h 02m
Deal found 9/15![United Airlines logo]()
$549
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/195:25 am -
Nonstop3h 00m
Sat 10/2412:15 pm -
Nonstop2h 35m
Deal found 9/15![Southwest logo]()
$484
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/2510:25 pm -
1 stop9h 30m
Sat 11/288:10 am -
Nonstop2h 30m
Deal found 9/15![Southwest logo]()
$484
This Southwest deal was found by Cheapflights users on 9/11. 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.
Fri 10/27:30 pm -
1 stop5h 05m
Mon 10/54:30 pm -
2 stops6h 40m
Deal found 9/11![Southwest logo]()
$495
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/2711:45 am -
Nonstop3h 00m
Fri 10/305:50 am -
Nonstop2h 35m
Deal found 9/13![Southwest logo]()
$496
This Southwest deal was found by Cheapflights users on 9/11. 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.
Thu 10/85:25 am -
Nonstop3h 00m
Sun 10/115:40 am -
1 stop7h 05m
Deal found 9/11![Southwest logo]()
$506
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/110:40 am -
2 stops8h 25m
Mon 10/55:50 pm -
1 stop5h 05m
Deal found 9/15![Southwest logo]()
$508
This Southwest deal was found by Cheapflights users on 9/12. 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.
Thu 10/155:35 am -
2 stops7h 00m
Sat 10/1711:55 am -
2 stops6h 55m
Deal found 9/12![Southwest logo]()
$526
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/52:30 pm -
1 stop5h 40m
Sun 11/85:15 am -
2 stops8h 15m
Deal found 9/15![Southwest logo]()
$531
This Southwest deal was found by Cheapflights users on 9/12. 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.
Fri 10/165:35 am -
2 stops7h 00m
Sun 10/184:35 pm -
1 stop6h 35m
Deal found 9/12![Southwest logo]()
$536
Last-minute flights from Boston to St. CharlesDiscover last-minute flight deals from Boston to St. Charles. Data last updated September 15, 2026 and is based on user searches.
Discover last-minute flight deals from Boston to St. Charles. Data last updated September 15, 2026 and is based on user searches.
This Delta 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 10/57:10 pm -
1 stop5h 32m
Tue 10/610:35 am -
1 stop4h 40m
Deal found 9/14![Delta logo]()
$343
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.
Tue 10/612:52 pm -
1 stop25h 18m
Mon 10/126:35 pm -
1 stop16h 17m
Deal found 9/14![Frontier logo]()
$337
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.
Tue 10/612:52 pm -
1 stop25h 18m
Thu 10/154:30 pm -
1 stop17h 32m
Deal found 9/14![Frontier logo]()
$341
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/75:35 am -
2 stops8h 15m
Wed 10/148:30 am -
2 stops6h 35m
Deal found 9/14![Southwest logo]()
$353
This Trip.com deal was found by Cheapflights users on 9/11. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/1111:47 am -
1 stop12h 26m
Sun 10/184:30 pm -
1 stop17h 32m
Deal found 9/11![Frontier logo]()
$344
This United Airlines 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/138:05 am -
1 stop5h 08m
Thu 10/157:30 am -
1 stop6h 05m
Deal found 9/15![United Airlines logo]()
$338
This Kiwi.com deal was found by Cheapflights users on 9/12. 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 10/1312:57 pm -
1 stop29h 43m
Thu 10/154:30 pm -
1 stop17h 32m
Deal found 9/12![Frontier logo]()
$348
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/157:15 am -
Nonstop3h 14m
Thu 10/226:00 am -
1 stop5h 44m
Deal found 9/15![American Airlines logo]()
$355
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 10/1711:47 am -
1 stop12h 26m
Sun 10/184:30 pm -
1 stop17h 32m
Deal found 9/15![Frontier logo]()
$351
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 10/207:15 am -
Nonstop3h 14m
Fri 10/236:10 pm -
Nonstop2h 47m
Deal found 9/14![American Airlines logo]()
$346
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.
Tue 10/2012:57 pm -
1 stop29h 43m
Sun 10/254:30 pm -
1 stop17h 32m
Deal found 9/15![Frontier logo]()
$350
This American Airlines 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/297:15 am -
Nonstop3h 14m
Mon 11/29:50 am -
Nonstop2h 36m
Deal found 9/15![American Airlines logo]()
$345
One-way flights from Boston to St. CharlesSearch for one-way flight options from Boston to St. Charles. Find affordable one-way fares based on user searches. Data last updated September 15, 2026.
Search for one-way flight options from Boston to St. Charles. Find affordable one-way fares based on user searches. Data last updated September 15, 2026.
This Frontier deal was found by Cheapflights users on 9/10. 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.
Mon 12/711:57 am -
1 stop13h 44m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Frontier logo]()
$135
This CheapOair deal was found by Cheapflights users on 9/12. 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 12/1211:57 am -
1 stop13h 44m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/12![Frontier logo]()
$140
This Frontier 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/1011:57 am -
1 stop13h 44m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Frontier logo]()
$145
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.
Tue 11/1712:15 pm -
1 stop30h 25m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/14![Frontier logo]()
$146
This American Airlines deal was found by Cheapflights users on 9/10. 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 10/67:15 am -
Nonstop3h 14m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![American Airlines logo]()
$149
This Frontier deal was found by Cheapflights users on 9/11. 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 10/111:17 am -
1 stop7h 37m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Frontier logo]()
$150
This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 11/145:35 am -
Nonstop3h 05m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/13![Southwest logo]()
$151
This Frontier deal was found by Cheapflights users on 9/10. 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 10/1511:47 am -
1 stop12h 26m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/10![Frontier logo]()
$155
This Kiwi.com deal was found by Cheapflights users on 9/11. 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 11/1012:15 pm -
2 stops28h 08m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Frontier logo]()
$159
This Kiwi.com deal was found by Cheapflights users on 9/11. 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 10/1312:57 pm -
1 stop29h 43m
Wed 12/3112:00 am -
Nonstop0h 00m
Deal found 9/11![Frontier logo]()
$162
Find 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, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $337 (Kiwi.com) |
One-way from | $135 (Frontier) |
Popular in | July |
Cheapest in | January |
Average price | $506 |
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 7,457,451 searches. Data last updated September 15, 2026.
Use the filters below to find and compare flights from Boston to St. Charles that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Wed 10/14
10:36 am-3:43 pm
1 stop6h 07m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$159
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Tue 11/17
4:57 pm-8:29 pm
1 stop4h 32m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$161
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Thu 10/15
5:35 am-11:35 am
2 stops7h 00m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$194
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Fri 11/13
9:00 am-3:54 pm
1 stop7h 54m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$206
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Sun 10/4
12:54 pm-1:10 pm
1 stop25h 16m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$226
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Sat 11/21
3:00 pm-10:50 pm
2 stops8h 50m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$228
Quickest round-trip
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Sun 10/25
7:15 am-9:29 am
Nonstop3h 14m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$260
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Fri 1/22
8:45 am-1:50 pm
1 stop6h 05m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$266
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Sun 12/13
2:25 pm-9:00 pm
2 stops7h 35m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$271
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Mon 11/9
10:30 am-9:40 pm
2 stops12h 10m
Lambert-St Louis
Wed 12/31
12:00 am-1:00 am
Nonstop0h 00m
$273
Showing 1-10 of 24 resultsSorted by cheapest first
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.
BOS-STL
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
BOS-CH5
BOS-STL
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, 2026.
It’s optimal to fly from Boston to St. Charles in the evening. By choosing this option you can save up to 15% on the cost of your flight, compared to a flight at noon.
How much does it cost to fly round-trip from Boston to St. Charles?
Airfare is below average for this route at the moment.
Boston to St. Charles flights typically cost between $385 and $679 in October.The cheapest round-trip price found within the last 5 days was $337 on Frontier (Oct 6-Oct 12).
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 September 12, 2026.
Travelers seeking maximum savings on their Boston to St. Charles flight should consider departing on Thursday evenings when fares are most often at their lowest. Sunday at noon 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 September 15, 2026.
Peruse reviews from past customers who have flown with Southwest,Delta, andAmerican 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.
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Reviews
1 / 20
4.0
OkaySteven,Sep 2026
OGG - HNL
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Reviews
1 / 20
4.0
OkaySteven,Sep 2026
OGG - HNL
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Reviews
1 / 20
4.0
OkaySteven,Sep 2026
OGG - HNL
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Reviews
1 / 20
4.0
OkaySteven,Sep 2026
OGG - HNL
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Reviews
1 / 20
4.0
OkaySteven,Sep 2026
OGG - HNL
Food
7.0
Comfort
8.0
Overall
8.0
Entertainment
7.5
Boarding
8.1
Crew
8.6
Reviews
1 / 20
4.0
OkaySteven,Sep 2026
OGG - HNL
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.
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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 7,457,451 searches. Data last updated September 15, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$90 | Average$255 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$148 | Average$555 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$297 | Average$408 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$318 | Average$535 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$327 | Average$437 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$341 | Average$521 | FlexibilityNo cancel fee | On-time63% |