$104+ Cheap flights from Boston to St. Louis (BOS - STL)
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 8/4. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — STL
Aug 17 — Aug 241
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. Louis 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 Lambert-St Louis are usually found in August or January, booked 51 days in advance, depart on a Wednesday or Thursday and return on a Wednesday
Cheap flight deals from Boston to St. Louis
Cheapest
Best
Last-minute
One-way
Cheapest flights from Boston to St. LouisExplore the most affordable flight options available from Boston to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 18, 2026.
Explore the most affordable flight options available from Boston to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on July 18, 2026.
This Kiwi.com deal was found by Cheapflights users on 7/14. 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 8/611:59 am
BOS
- STL
1 stop21h 58m
Frontier
Sun 8/236:17 pm
STL
- BOS
1 stop13h 24m
Frontier
Deal found 7/14![Frontier logo]()
$325
This Southwest deal was found by Cheapflights users on 7/14. 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.
Thu 10/85:35 am
BOS
- STL
1 stop5h 55m
Southwest
Mon 10/125:55 am
STL
- BOS
Nonstop2h 35m
Southwest
Deal found 7/14![Southwest logo]()
$327
This Kiwi.com deal was found by Cheapflights users on 7/14. 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 8/1311:59 am
BOS
- STL
1 stop6h 38m
Frontier
Sun 8/166:34 pm
STL
- BOS
2 stops15h 30m
Frontier
Deal found 7/14![Frontier logo]()
$328
This American Airlines deal was found by Cheapflights users on 7/15. 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.
Wed 9/236:20 am
BOS
- STL
Nonstop3h 00m
American Airlines
Wed 9/234:37 pm
STL
- BOS
1 stop5h 03m
American Airlines
Deal found 7/15![American Airlines logo]()
$329
This Frontier deal was found by Cheapflights users on 7/15. 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.
Thu 7/3011:52 am
BOS
- STL
1 stop6h 45m
Frontier
Sun 8/26:34 pm
STL
- BOS
1 stop12h 12m
Frontier
Deal found 7/15![Frontier logo]()
$331
This Southwest deal was found by Cheapflights users on 7/14. 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.
Fri 8/2112:40 pm
BOS
- STL
2 stops7h 30m
Southwest
Wed 8/2610:45 am
STL
- BOS
2 stops6h 50m
Southwest
Deal found 7/14![Southwest logo]()
$332
This Kiwi.com deal was found by Cheapflights users on 7/15. 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.
Thu 10/1512:34 pm
BOS
- STL
2 stops22h 06m
Multiple Airlines
Sun 10/1810:35 am
STL
- BOS
1 stop23h 17m
Multiple Airlines
Deal found 7/15![Multiple Airlines logo]()
$335
This Delta deal was found by Cheapflights users on 7/16. 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 10/175:45 am
BOS
- STL
1 stop6h 06m
Delta
Sat 10/175:28 pm
STL
- BOS
1 stop5h 20m
Delta
Deal found 7/16![Delta logo]()
$337
This Southwest deal was found by Cheapflights users on 7/17. 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 8/139:40 am
BOS
- STL
2 stops6h 30m
Southwest
Wed 8/196:40 pm
STL
- BOS
Nonstop2h 35m
Southwest
Deal found 7/17![Southwest logo]()
$338
This Super.com deal was found by Cheapflights users on 7/15. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/2811:52 am
BOS
- STL
1 stop6h 45m
Frontier
Thu 7/306:34 pm
STL
- BOS
1 stop12h 12m
Frontier
Deal found 7/15![Frontier logo]()
$339
Best flights from Boston to St. LouisDiscover carefully curated flight deals from Boston to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 18, 2026.
Discover carefully curated flight deals from Boston to St. Louis that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated July 18, 2026.
This Southwest deal was found by Cheapflights users on 7/13. 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.
Wed 8/125:35 am
BOS
- STL
Nonstop2h 50m
Southwest
Sun 8/168:20 am
STL
- BOS
Nonstop2h 35m
Southwest
Deal found 7/13![Southwest logo]()
$374
This United Airlines deal was found by Cheapflights users on 7/15. 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.
Sat 8/156:00 pm
BOS
- STL
1 stop6h 38m
United Airlines
Thu 8/207:00 am
STL
- BOS
1 stop6h 22m
United Airlines
Deal found 7/15![United Airlines logo]()
$392
This Delta deal was found by Cheapflights users on 7/15. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/165:30 am
BOS
- STL
1 stop5h 07m
Delta
Sat 8/226:09 pm
STL
- BOS
1 stop4h 50m
Delta
Deal found 7/15![Delta logo]()
$394
This Southwest deal was found by Cheapflights users on 7/14. 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.
Tue 9/225:35 am
BOS
- STL
Nonstop2h 50m
Southwest
Thu 9/247:00 am
STL
- BOS
Nonstop2h 35m
Southwest
Deal found 7/14![Southwest logo]()
$374
This United Airlines deal was found by Cheapflights users on 7/13. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/248:00 am
BOS
- STL
1 stop5h 13m
United Airlines
Tue 9/298:00 am
STL
- BOS
2 stops10h 25m
United Airlines
Deal found 7/13![United Airlines logo]()
$402
This Southwest deal was found by Cheapflights users on 7/15. 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 8/275:00 am
BOS
- STL
Nonstop2h 50m
Southwest
Sun 8/308:20 am
STL
- BOS
Nonstop2h 35m
Southwest
Deal found 7/15![Southwest logo]()
$374
This United Airlines deal was found by Cheapflights users on 7/17. 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 8/185:45 am
BOS
- STL
2 stops10h 53m
United Airlines
Sat 8/225:30 pm
STL
- BOS
1 stop5h 04m
United Airlines
Deal found 7/17![United Airlines logo]()
$402
This Southwest deal was found by Cheapflights users on 7/15. 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 8/175:00 am
BOS
- STL
Nonstop2h 50m
Southwest
Fri 8/217:00 pm
STL
- BOS
Nonstop2h 30m
Southwest
Deal found 7/15![Southwest logo]()
$374
This Southwest deal was found by Cheapflights users on 7/14. 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.
Mon 8/315:50 pm
BOS
- STL
Nonstop2h 55m
Southwest
Fri 9/44:15 pm
STL
- BOS
1 stop4h 55m
Southwest
Deal found 7/14![Southwest logo]()
$384
This Southwest deal was found by Cheapflights users on 7/12. 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 8/135:00 am
BOS
- STL
Nonstop2h 50m
Southwest
Sun 8/166:00 am
STL
- BOS
1 stop6h 15m
Southwest
Deal found 7/12![Southwest logo]()
$384
This Southwest deal was found by Cheapflights users on 7/17. 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 9/41:30 pm
BOS
- STL
2 stops9h 35m
Southwest
Mon 9/75:45 am
STL
- BOS
1 stop6h 00m
Southwest
Deal found 7/17![Southwest logo]()
$399
Last-minute flights from Boston to St. LouisDiscover last-minute flight deals from Boston to St. Louis. Data last updated July 18, 2026 and is based on user searches.
Discover last-minute flight deals from Boston to St. Louis. Data last updated July 18, 2026 and is based on user searches.
This Super.com deal was found by Cheapflights users on 7/15. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 7/2811:52 am
BOS
- STL
1 stop6h 45m
Frontier
Thu 7/306:34 pm
STL
- BOS
1 stop12h 12m
Frontier
Deal found 7/15![Frontier logo]()
$339
This Frontier deal was found by Cheapflights users on 7/15. 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.
Thu 7/3011:52 am
BOS
- STL
1 stop6h 45m
Frontier
Sun 8/26:34 pm
STL
- BOS
1 stop12h 12m
Frontier
Deal found 7/15![Frontier logo]()
$331
This Trip.com deal was found by Cheapflights users on 7/16. 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.
Sat 8/110:04 am
BOS
- STL
1 stop14h 55m
Frontier
Sun 8/24:09 pm
STL
- BOS
1 stop16h 00m
Frontier
Deal found 7/16![Frontier logo]()
$329
This Kiwi.com deal was found by Cheapflights users on 7/14. 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 8/611:59 am
BOS
- STL
1 stop21h 58m
Frontier
Sun 8/236:17 pm
STL
- BOS
1 stop13h 24m
Frontier
Deal found 7/14![Frontier logo]()
$325
This Kiwi.com deal was found by Cheapflights users on 7/14. 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 8/1311:59 am
BOS
- STL
1 stop6h 38m
Frontier
Sun 8/166:34 pm
STL
- BOS
2 stops15h 30m
Frontier
Deal found 7/14![Frontier logo]()
$328
This Southwest deal was found by Cheapflights users on 7/17. 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 8/139:40 am
BOS
- STL
2 stops6h 30m
Southwest
Wed 8/196:40 pm
STL
- BOS
Nonstop2h 35m
Southwest
Deal found 7/17![Southwest logo]()
$338
This Southwest deal was found by Cheapflights users on 7/12. 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.
Sat 8/155:50 am
BOS
- STL
1 stop6h 00m
Southwest
Sat 8/228:30 am
STL
- BOS
2 stops8h 00m
Southwest
Deal found 7/12![Southwest logo]()
$342
This Southwest deal was found by Cheapflights users on 7/14. 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.
Fri 8/2112:40 pm
BOS
- STL
2 stops7h 30m
Southwest
Wed 8/2610:45 am
STL
- BOS
2 stops6h 50m
Southwest
Deal found 7/14![Southwest logo]()
$332
This Southwest deal was found by Cheapflights users on 7/13. 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.
Fri 8/287:40 am
BOS
- STL
1 stop4h 55m
Southwest
Sat 8/295:45 am
STL
- BOS
2 stops7h 25m
Southwest
Deal found 7/13![Southwest logo]()
$327
This Kiwi.com deal was found by Cheapflights users on 7/14. 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 8/319:36 am
BOS
- STL
1 stop8h 46m
Frontier
Fri 9/46:17 pm
STL
- BOS
1 stop16h 30m
Frontier
Deal found 7/14![Frontier logo]()
$341
One-way flights from Boston to St. LouisSearch for one-way flight options from Boston to St. Louis. Find affordable one-way fares based on user searches. Data last updated July 18, 2026.
Search for one-way flight options from Boston to St. Louis. Find affordable one-way fares based on user searches. Data last updated July 18, 2026.
This Super.com deal was found by Cheapflights users on 7/14. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/411:52 am
BOS
- STL
1 stop6h 45m
Frontier
Deal found 7/14![Frontier logo]()
$104
This Expedia deal was found by Cheapflights users on 7/14. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 8/1110:04 am
BOS
- STL
1 stop14h 55m
Frontier
Deal found 7/14![Frontier logo]()
$114
This Frontier deal was found by Cheapflights users on 7/17. 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 8/1311:59 am
BOS
- STL
1 stop6h 38m
Frontier
Deal found 7/17![Frontier logo]()
$121
This Frontier deal was found by Cheapflights users on 7/17. 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 8/319:36 am
BOS
- STL
1 stop8h 46m
Frontier
Deal found 7/17![Frontier logo]()
$122
This Kiwi.com deal was found by Cheapflights users on 7/16. 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 9/171:00 pm
BOS
- STL
2 stops45h 40m
Frontier
Deal found 7/16![Frontier logo]()
$126
This Kiwi.com deal was found by Cheapflights users on 7/13. 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.
Tue 9/151:00 pm
BOS
- STL
1 stop21h 40m
Frontier
Deal found 7/13![Frontier logo]()
$127
This Frontier deal was found by Cheapflights users on 7/13. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/1411:05 am
BOS
- STL
1 stop9h 34m
Frontier
Deal found 7/13![Frontier logo]()
$129
This Priceline deal was found by Cheapflights users on 7/15. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/310:04 am
BOS
- STL
1 stop7h 07m
Frontier
Deal found 7/15![Frontier logo]()
$130
This Kiwi.com deal was found by Cheapflights users on 7/16. 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 9/121:00 pm
BOS
- STL
1 stop21h 40m
Frontier
Deal found 7/16![Frontier logo]()
$131
This Super.com deal was found by Cheapflights users on 7/14. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/289:36 am
BOS
- STL
1 stop8h 46m
Frontier
Deal found 7/14![Frontier logo]()
$133
This Super.com deal was found by Cheapflights users on 7/14. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 8/219:36 am
BOS
- STL
1 stop8h 46m
Frontier
Deal found 7/14![Frontier logo]()
$134
Find flight deals from Boston to St. Louis
Discover tips and strategies to find the most affordable flight options for your journey from Boston (BOS) to St. Louis (STL). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated July 18, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $325 (Kiwi.com) |
One-way from | $104 (Super.com) |
Popular in | July |
Cheapest in | August |
Average price | $566 |
Good round-trip deal | $396 or less |
Good one-way deal | $215 or less |
Cheapflights Fare Finder
Customize your flight search to find flights from Boston to St. Louis 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 July 18, 2026.
Use the filters below to find and compare flights from Boston to St. Louis that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Wed 8/12
5:35 am-7:25 am
Nonstop2h 50m
Lambert-St Louis
Sun 8/16
8:20 am-11:55 am
Nonstop2h 35m
$374
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Tue 9/22
5:35 am-7:25 am
Nonstop2h 50m
Lambert-St Louis
Thu 9/24
7:00 am-10:35 am
Nonstop2h 35m
$374
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Thu 8/27
5:00 am-6:50 am
Nonstop2h 50m
Lambert-St Louis
Sun 8/30
8:20 am-11:55 am
Nonstop2h 35m
$374
Quickest round-trip
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Mon 8/17
5:00 am-6:50 am
Nonstop2h 50m
Lambert-St Louis
Fri 8/21
7:00 pm-10:30 pm
Nonstop2h 30m
$374
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Mon 8/31
5:50 pm-7:45 pm
Nonstop2h 55m
Lambert-St Louis
Fri 9/4
4:15 pm-10:10 pm
1 stop4h 55m
$384
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Thu 8/13
5:00 am-6:50 am
Nonstop2h 50m
Lambert-St Louis
Sun 8/16
6:00 am-1:15 pm
1 stop6h 15m
$384
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Sat 8/15
6:00 pm-11:38 pm
1 stop6h 38m
Lambert-St Louis
Thu 8/20
7:00 am-2:22 pm
1 stop6h 22m
$392
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Sun 8/16
5:30 am-9:37 am
1 stop5h 07m
Lambert-St Louis
Sat 8/22
6:09 pm-11:59 pm
1 stop4h 50m
$394
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Fri 9/4
1:30 pm-10:05 pm
2 stops9h 35m
Lambert-St Louis
Mon 9/7
5:45 am-12:45 pm
1 stop6h 00m
$399
BostonSt. Louis
BOS - STL
BOSSTL
Boston Logan Intl
Thu 9/24
8:00 am-12:13 pm
1 stop5h 13m
Lambert-St Louis
Tue 9/29
8:00 am-7:25 pm
2 stops10h 25m
$402
Showing 1-10 of 20 resultsSorted by cheapest first
Compare providers for flights from Boston to St. Louis
Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Boston to St. Louis in July.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars | |
| Price Accuracy- | Trust Score*1 star | |
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy1 star | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Boston-St. Louis flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Boston-St. Louis flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Boston-St. Louis flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Boston-St. Louis flights, Cheapflights users trust FlightHub the most. FlightHub has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Boston-St. Louis flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.
Best time to book a flight from Boston to St. Louis
Have a flexible travel schedule? Discover the best time to fly to St. Louis 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. Louis
Prices
Delays
How far ahead should I book a flight from Boston to St. Louis?
To ensure you get the cheapest price possible for a flight from Boston to St. Louis, you should look to book at least 50 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. Louis?
Currently, August is the cheapest month in which you can book a flight from Boston to St. Louis (average of $382). Flying from Boston to St. Louis in July is currently the most expensive (average of $566). 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 STL?
Find hourly flight availability from Boston to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated July 18, 2026.
It’s typically best to fly out from Boston to St. Louis in the evening. Doing so could potentially save you 9% on the flight price compared to flying in the afternoon, which is usually more expensive.
What is the cheapest day to fly from Boston to St. Louis?
Use this chart to determine the cheapest time to fly round-trip from Boston to St. Louis. Price data was last updated on July 11, 2026.
Travelers seeking maximum savings on their Boston to St. Louis 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 often are flights from Boston to St. Louis delayed?
About 20% of weekly flights between Boston and St. Louis have experienced delays in the past year, with the average delay time being 140 minutes.
What is the most punctual flight time for Boston to St. Louis flights?
Historically, flights departing at night are less likely to be delayed, whereas flights leaving in the evening tend to experience delays more often.
What day of the week experiences the fewest flight delays on this route?
Saturday tends to have the lowest number of delays on this route, whereas Sunday has historically faced a higher average of delays compared to other days of the week.
Which airline has the best punctuality record on Boston to St. Louis flights?
Over the last year, American Airlines have had the lowest number of delays on this route, with just 15% of flights being delayed.
The best insider tips for Boston to St. Louis flights
AI-powered summary based on content written by travel experts. AI can make mistakes.
Cheapflights partnered with top experts to bring you the best recommendations for your Boston to St. Louis trip
Our travel experts
Reviews of airlines servicing St. Louis
Get insights into the airlines that provide service to St. Louis. 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. Louis. Reviews last updated July 18, 2026.
Read through reviews of airlines operating flights from Boston to St. Louis, such as Southwest,Delta, andAmerican Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Comfort
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Boarding
8.1
Crew
8.6
Food
7.0
Overall
8.0
Entertainment
7.5
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Related info for your journey
Find useful and relevant information for your journey from Boston to St. Louis. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near St. Louis?
Book flights to St. Louis if you plan to visit one of these locationsEdwardsville
O'Fallon
Fenton
Swansea
Fairview Heights
Eureka
Maryland Heights
Collinsville
Wentzville
Glencoe
Chesterfield
Alton
Farmington
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
St. Louis flight routes
Alternative routes for Boston to St. Louis
See prices for flight routes from nearby airports that may be better suited for you.
Complete your trip
Complete your trip to St. Louis by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from Boston to St. Louis by cabin class
Find flights from Boston to St. Louis, based on your preferred cabin class, be it economy, premium economy, business, or first class.
Boston and St. Louis flights
Browse other Boston and St. Louis flight options. Last updated on July 18, 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 July 18, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Other flights to St. Louis
Explore flights to St. Louis departing from other origins. Flights are based on user searches made on Cheapflights and were last updated on July 18, 2026.
Top 5 airlines flying from Boston to St. Louis
Discover the top 5 airlines that operate flights from Boston to St. Louis. 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 July 18, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$90 | Average$255 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$148 | Average$516 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$288 | Average$492 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$316 | Average$497 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$327 | Average$437 | FlexibilityNo cancel fee | On-time62% |