$82+ 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 5/26. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — STL
May 30 — Jun 61
Round-trip
1 adult, Economy
We work with more than 300 partners to bring you better travel deals
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 August or September, booked 45 days in advance, depart on a Thursday or Wednesday 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 April 30, 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 April 30, 2026.
This American Airlines deal was found by Cheapflights users on 4/27. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/305:05 am
BOS
- STL
1 stop9h 10m
American Airlines
Tue 6/25:08 am
STL
- BOS
1 stop5h 44m
American Airlines
Deal found 4/27![American Airlines logo]()
$342
This Expedia deal was found by Cheapflights users on 4/25. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 7/56:00 am
BOS
- STL
1 stop12h 37m
Frontier
Fri 7/104:52 pm
STL
- BOS
1 stop7h 31m
Frontier
Deal found 4/25![Frontier logo]()
$344
This American Airlines deal was found by Cheapflights users on 4/25. 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 6/42:05 pm
BOS
- STL
1 stop7h 47m
American Airlines
Tue 6/99:39 am
STL
- BOS
Nonstop2h 45m
American Airlines
Deal found 4/25![American Airlines logo]()
$345
This Kiwi.com deal was found by Cheapflights users on 4/26. 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 6/157:00 am
BOS
- STL
1 stop18h 09m
Multiple Airlines
Wed 6/175:06 pm
STL
- BOS
1 stop7h 21m
Multiple Airlines
Deal found 4/26![Multiple Airlines logo]()
$347
This Kiwi.com deal was found by Cheapflights users on 4/26. 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 5/219:18 am
BOS
- STL
1 stop7h 57m
Frontier
Mon 5/255:27 pm
STL
- BOS
1 stop13h 22m
Frontier
Deal found 4/26![Frontier logo]()
$348
This Kiwi.com deal was found by Cheapflights users on 4/26. 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 5/196:00 am
BOS
- STL
1 stop12h 33m
Frontier
Sun 5/249:06 pm
STL
- BOS
2 stops33h 43m
Frontier
Deal found 4/26![Frontier logo]()
$349
This American Airlines deal was found by Cheapflights users on 4/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/305:05 am
BOS
- STL
1 stop9h 10m
American Airlines
Mon 6/17:51 pm
STL
- BOS
Nonstop2h 45m
American Airlines
Deal found 4/28![American Airlines logo]()
$350
This Kiwi.com deal was found by Cheapflights users on 4/29. 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.
Mon 5/257:00 am
BOS
- STL
1 stop17h 57m
Multiple Airlines
Tue 5/266:33 pm
STL
- BOS
1 stop12h 16m
Multiple Airlines
Deal found 4/29![Multiple Airlines logo]()
$351
This Southwest deal was found by Cheapflights users on 4/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/285:40 am
BOS
- STL
Nonstop3h 00m
Southwest
Thu 5/287:40 pm
STL
- BOS
Nonstop2h 30m
Southwest
Deal found 4/28![Southwest logo]()
$353
This Kiwi.com deal was found by Cheapflights users on 4/29. 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 6/189:10 am
BOS
- STL
1 stop9h 20m
Frontier
Mon 6/227:38 pm
STL
- BOS
2 stops28h 49m
Frontier
Deal found 4/29![Frontier logo]()
$354
This Delta deal was found by Cheapflights users on 4/29. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/15:15 pm
BOS
- STL
1 stop4h 54m
Delta
Wed 6/34:25 pm
STL
- BOS
1 stop5h 37m
Delta
Deal found 4/29![Delta logo]()
$355
This Kiwi.com deal was found by Cheapflights users on 4/28. 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.
Mon 6/299:36 pm
BOS
- STL
2 stops20h 54m
Multiple Airlines
Sat 7/45:06 pm
STL
- BOS
1 stop7h 21m
Multiple Airlines
Deal found 4/28![Multiple Airlines logo]()
$356
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 April 30, 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 April 30, 2026.
This Delta deal was found by Cheapflights users on 4/26. 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 6/12:00 pm
BOS
- STL
1 stop7h 39m
Delta
Wed 6/34:25 pm
STL
- BOS
1 stop5h 37m
Delta
Deal found 4/26![Delta logo]()
$355
This Southwest deal was found by Cheapflights users on 4/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/3011:50 am
BOS
- STL
Nonstop2h 55m
Southwest
Thu 6/412:40 pm
STL
- BOS
1 stop5h 40m
Southwest
Deal found 4/30![Southwest logo]()
$363
This United Airlines deal was found by Cheapflights users on 4/29. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/275:45 am
BOS
- STL
2 stops9h 38m
United Airlines
Wed 6/311:25 am
STL
- BOS
2 stops11h 34m
United Airlines
Deal found 4/29![United Airlines logo]()
$437
This Southwest deal was found by Cheapflights users on 4/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/95:45 pm
BOS
- STL
Nonstop2h 55m
Southwest
Sun 9/131:50 pm
STL
- BOS
Nonstop2h 35m
Southwest
Deal found 4/29![Southwest logo]()
$389
This Southwest deal was found by Cheapflights users on 4/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 6/155:35 am
BOS
- STL
Nonstop2h 50m
Southwest
Wed 6/171:45 pm
STL
- BOS
1 stop8h 45m
Southwest
Deal found 4/29![Southwest logo]()
$405
This Southwest deal was found by Cheapflights users on 4/25. 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 6/55:35 am
BOS
- STL
Nonstop2h 50m
Southwest
Sat 6/68:45 pm
STL
- BOS
Nonstop2h 30m
Southwest
Deal found 4/25![Southwest logo]()
$407
This Southwest deal was found by Cheapflights users on 4/30. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 7/255:50 am
BOS
- STL
Nonstop2h 55m
Southwest
Tue 7/287:10 pm
STL
- BOS
Nonstop2h 30m
Southwest
Deal found 4/30![Southwest logo]()
$411
This Southwest deal was found by Cheapflights users on 4/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/75:50 am
BOS
- STL
Nonstop2h 55m
Southwest
Mon 6/85:35 pm
STL
- BOS
1 stop5h 35m
Southwest
Deal found 4/28![Southwest logo]()
$417
This Southwest deal was found by Cheapflights users on 4/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 5/267:35 am
BOS
- STL
2 stops8h 35m
Southwest
Wed 5/277:35 am
STL
- BOS
2 stops7h 20m
Southwest
Deal found 4/29![Southwest logo]()
$432
This Southwest deal was found by Cheapflights users on 4/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/285:50 am
BOS
- STL
Nonstop2h 55m
Southwest
Sun 7/58:00 pm
STL
- BOS
Nonstop2h 30m
Southwest
Deal found 4/28![Southwest logo]()
$461
This Southwest deal was found by Cheapflights users on 4/29. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/45:00 am
BOS
- STL
Nonstop2h 50m
Southwest
Mon 9/77:00 am
STL
- BOS
Nonstop2h 35m
Southwest
Deal found 4/29![Southwest logo]()
$461
This Southwest deal was found by Cheapflights users on 4/27. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/125:35 am
BOS
- STL
Nonstop2h 50m
Southwest
Sun 6/148:00 pm
STL
- BOS
Nonstop2h 30m
Southwest
Deal found 4/27![Southwest logo]()
$461
Last-minute flights from Boston to St. CharlesDiscover last-minute flight deals from Boston to St. Charles. Data last updated April 30, 2026 and is based on user searches.
Discover last-minute flight deals from Boston to St. Charles. Data last updated April 30, 2026 and is based on user searches.
This Kiwi.com deal was found by Cheapflights users on 4/28. 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.
Thu 5/147:00 am
BOS
- STL
1 stop18h 21m
Multiple Airlines
Sun 5/176:55 pm
STL
- BOS
1 stop29h 29m
Multiple Airlines
Deal found 4/28![Multiple Airlines logo]()
$358
This Kiwi.com deal was found by Cheapflights users on 4/29. 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.
Mon 5/187:00 am
BOS
- STL
1 stop18h 21m
Multiple Airlines
Tue 5/196:33 pm
STL
- BOS
2 stops15h 33m
Multiple Airlines
Deal found 4/29![Multiple Airlines logo]()
$357
This American Airlines deal was found by Cheapflights users on 4/26. 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 5/193:00 pm
BOS
- STL
Nonstop3h 12m
American Airlines
Mon 5/256:00 am
STL
- BOS
1 stop4h 50m
American Airlines
Deal found 4/26![American Airlines logo]()
$345
This Kiwi.com deal was found by Cheapflights users on 4/26. 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 5/196:00 am
BOS
- STL
1 stop12h 33m
Frontier
Sun 5/249:06 pm
STL
- BOS
2 stops33h 43m
Frontier
Deal found 4/26![Frontier logo]()
$349
This Kiwi.com deal was found by Cheapflights users on 4/26. 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 5/219:18 am
BOS
- STL
1 stop7h 57m
Frontier
Mon 5/255:27 pm
STL
- BOS
1 stop13h 22m
Frontier
Deal found 4/26![Frontier logo]()
$348
This Kiwi.com deal was found by Cheapflights users on 4/29. 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.
Mon 5/257:00 am
BOS
- STL
1 stop17h 57m
Multiple Airlines
Tue 5/266:33 pm
STL
- BOS
1 stop12h 16m
Multiple Airlines
Deal found 4/29![Multiple Airlines logo]()
$351
This Southwest deal was found by Cheapflights users on 4/28. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/285:40 am
BOS
- STL
Nonstop3h 00m
Southwest
Thu 5/287:40 pm
STL
- BOS
Nonstop2h 30m
Southwest
Deal found 4/28![Southwest logo]()
$353
This Kiwi.com deal was found by Cheapflights users on 4/29. 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.
Fri 5/298:44 am
BOS
- STL
2 stops25h 11m
Frontier
Sun 5/316:33 pm
STL
- BOS
1 stop12h 16m
Frontier
Deal found 4/29![Frontier logo]()
$359
This American Airlines deal was found by Cheapflights users on 4/27. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/305:05 am
BOS
- STL
1 stop9h 10m
American Airlines
Tue 6/25:08 am
STL
- BOS
1 stop5h 44m
American Airlines
Deal found 4/27![American Airlines logo]()
$342
This American Airlines deal was found by Cheapflights users on 4/28. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/305:05 am
BOS
- STL
1 stop9h 10m
American Airlines
Mon 6/17:51 pm
STL
- BOS
Nonstop2h 45m
American Airlines
Deal found 4/28![American Airlines logo]()
$350
This American Airlines deal was found by Cheapflights users on 4/30. 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.
Sat 5/308:00 am
BOS
- STL
1 stop4h 59m
American Airlines
Sat 6/69:11 am
STL
- BOS
1 stop8h 39m
American Airlines
Deal found 4/30![American Airlines logo]()
$360
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 April 30, 2026.
Search for one-way flight options from Boston to St. Charles. Find affordable one-way fares based on user searches. Data last updated April 30, 2026.
This Kiwi.com deal was found by Cheapflights users on 4/29. 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.
Tue 5/269:12 am
BOS
- STL
1 stop24h 43m
Frontier
Deal found 4/29![Frontier logo]()
$82
This Frontier deal was found by Cheapflights users on 4/29. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/246:00 am
BOS
- STL
1 stop12h 33m
Frontier
Deal found 4/29![Frontier logo]()
$86
This Kiwi.com deal was found by Cheapflights users on 4/30. 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 5/2712:01 pm
BOS
- STL
1 stop30h 32m
Frontier
Deal found 4/30![Frontier logo]()
$89
This Priceline deal was found by Cheapflights users on 4/26. 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.
Thu 5/149:31 am
BOS
- STL
1 stop8h 23m
Frontier
Deal found 4/26![Frontier logo]()
$100
This Kiwi.com deal was found by Cheapflights users on 4/27. 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.
Mon 6/112:01 pm
BOS
- STL
1 stop30h 32m
Frontier
Deal found 4/27![Frontier logo]()
$104
This Super.com deal was found by Cheapflights users on 4/30. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/1710:07 am
BOS
- STL
1 stop15h 14m
Frontier
Deal found 4/30![Frontier logo]()
$105
This Frontier deal was found by Cheapflights users on 4/29. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 5/286:00 am
BOS
- STL
1 stop12h 33m
Frontier
Deal found 4/29![Frontier logo]()
$106
This Kiwi.com deal was found by Cheapflights users on 4/27. 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.
Wed 5/275:45 am
BOS
- STL
2 stops36h 48m
Multiple Airlines
Deal found 4/27![Multiple Airlines logo]()
$110
This Priceline deal was found by Cheapflights users on 4/29. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/149:14 am
BOS
- STL
1 stop9h 23m
Frontier
Deal found 4/29![Frontier logo]()
$111
This Kiwi.com deal was found by Cheapflights users on 4/26. 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 5/245:45 am
BOS
- STL
2 stops28h 10m
Multiple Airlines
Deal found 4/26![Multiple Airlines logo]()
$121
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 April 30, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $342 (American Airlines) |
One-way from | $82 (Kiwi.com) |
Popular in | March |
Cheapest in | August |
Average price | $521 |
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 30, 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 - STL
BOSSTL
Boston Logan Intl
Mon 6/1
2:00 pm-8:39 pm
1 stop7h 39m
Lambert-St Louis
Wed 6/3
4:25 pm-11:02 pm
1 stop5h 37m
$355
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Sat 5/30
11:50 am-1:45 pm
Nonstop2h 55m
Lambert-St Louis
Thu 6/4
12:40 pm-7:20 pm
1 stop5h 40m
$363
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Wed 9/9
5:45 pm-7:40 pm
Nonstop2h 55m
Lambert-St Louis
Sun 9/13
1:50 pm-5:25 pm
Nonstop2h 35m
$389
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Mon 6/15
5:35 am-7:25 am
Nonstop2h 50m
Lambert-St Louis
Wed 6/17
1:45 pm-11:30 pm
1 stop8h 45m
$405
Quickest round-trip
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Fri 6/5
5:35 am-7:25 am
Nonstop2h 50m
Lambert-St Louis
Sat 6/6
8:45 pm-12:15 am
Nonstop2h 30m
$407
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Sat 7/25
5:50 am-7:45 am
Nonstop2h 55m
Lambert-St Louis
Tue 7/28
7:10 pm-10:40 pm
Nonstop2h 30m
$411
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Sun 6/7
5:50 am-7:45 am
Nonstop2h 55m
Lambert-St Louis
Mon 6/8
5:35 pm-12:10 am
1 stop5h 35m
$417
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Tue 5/26
7:35 am-3:10 pm
2 stops8h 35m
Lambert-St Louis
Wed 5/27
7:35 am-3:55 pm
2 stops7h 20m
$432
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Wed 5/27
5:45 am-2:23 pm
2 stops9h 38m
Lambert-St Louis
Wed 6/3
11:25 am-11:59 pm
2 stops11h 34m
$437
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Sun 6/28
5:50 am-7:45 am
Nonstop2h 55m
Lambert-St Louis
Sun 7/5
8:00 pm-11:30 pm
Nonstop2h 30m
$461
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 April 30, 2026.
It’s optimal to fly from Boston to St. Charles in the evening. By choosing this option you can save up to 8% on the cost of your flight, compared to a flight at noon.
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 April 25, 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.
How much does it cost to fly round-trip from Boston to St. Charles?
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 30, 2026.
Peruse reviews from past customers who have flown with Southwest,Delta, andJetBlue 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.
Entertainment
7.5
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
Entertainment
7.5
Comfort
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Overall
8.0
Reviews
1 / 20
2.0
MediocreDominic,Mar 2026
MCO - SMF
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.
Browse thousands of different options on Cheapflights for your next trip
Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.
Alternative routes
Complete your trip
Flights by cabin class
Other flight options
Other flights from Boston
Popular flights
Top destinations
Alternative routes for Boston to St. Charles
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to St. Charles by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Boston to St. Charles by cabin class
Find flights from Boston to St. Charles, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Boston and St. Charles flights
Browse other Boston and St. Charles flight options. Last updated on April 30, 2026.
Other flights from Boston
Browse through other flights departing from Boston. Flights are based on user searches made on Cheapflights and were last updated on April 30, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Boston to St. Charles flights
Consider these flights traveling from Boston to St. Charles.
Top 7 airlines flying from Boston to St. Charles
Discover the top 7 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 30, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$63 | Average$207 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$90 | Average$255 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$148 | Average$437 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$284 | Average$521 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$297 | Average$408 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$315 | Average$477 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$327 | Average$430 | FlexibilityNo cancel fee | On-time62% |