$108+ 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 9/10. Fares are subject to change and may not be available on all flights or dates of travel.
BOS — STL
Sep 10 — Sep 171
Round-trip
1 adult, Economy
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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 January or September, booked 51 days in advance, depart on a Wednesday or Saturday 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 August 11, 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 August 11, 2026.
This Kiwi.com deal was found by Cheapflights users on 8/9. 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 9/312:45 pm -
1 stop29h 37m
Mon 9/76:17 pm -
1 stop16h 30m
Deal found 8/9![Frontier logo]()
$339
This Frontier deal was found by Cheapflights users on 8/7. 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.
Fri 11/1310:11 am -
1 stop10h 28m
Sun 11/158:34 pm -
1 stop11h 42m
Deal found 8/7![Frontier logo]()
$340
This Frontier deal was found by Cheapflights users on 8/9. 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.
Tue 8/1111:59 am -
1 stop6h 38m
Sun 8/166:34 pm -
1 stop12h 12m
Deal found 8/9![Frontier logo]()
$341
This Southwest deal was found by Cheapflights users on 8/7. 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 9/55:50 am -
2 stops8h 35m
Sun 9/67:20 am -
1 stop6h 40m
Deal found 8/7![Southwest logo]()
$342
This Southwest deal was found by Cheapflights users on 8/9. 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 9/35:50 am -
1 stop6h 45m
Sun 9/62:45 pm -
1 stop6h 45m
Deal found 8/9![Southwest logo]()
$343
This Kiwi.com deal was found by Cheapflights users on 8/9. 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 9/2412:54 pm -
2 stops23h 23m
Mon 9/282:29 pm -
1 stop20h 38m
Deal found 8/9![Frontier logo]()
$344
This Southwest deal was found by Cheapflights users on 8/9. 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 9/235:35 am -
Nonstop2h 50m
Sat 9/2611:45 am -
2 stops9h 00m
Deal found 8/9![Southwest logo]()
$345
This Kiwi.com deal was found by Cheapflights users on 8/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/712:54 pm -
1 stop21h 46m
Sat 10/1010:35 am -
1 stop23h 17m
Deal found 8/9![Frontier logo]()
$346
This Kiwi.com deal was found by Cheapflights users on 8/9. 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 9/1112:54 pm -
2 stops23h 38m
Mon 9/142:29 pm -
1 stop20h 38m
Deal found 8/9![Frontier logo]()
$347
This Southwest deal was found by Cheapflights users on 8/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/181:30 pm -
1 stop9h 30m
Mon 9/217:00 pm -
Nonstop2h 35m
Deal found 8/10![Southwest logo]()
$349
This Southwest deal was found by Cheapflights users on 8/8. 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 9/55:30 am -
Nonstop2h 50m
Sat 9/124:15 pm -
Nonstop2h 40m
Deal found 8/8![Southwest logo]()
$350
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 August 11, 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 August 11, 2026.
This Southwest deal was found by Cheapflights users on 8/6. 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 11/111:10 pm -
Nonstop3h 10m
Thu 11/1210:15 am -
Nonstop2h 30m
Deal found 8/6![Southwest logo]()
$369
This United Airlines deal was found by Cheapflights users on 8/11. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/229:00 am -
1 stop7h 38m
Thu 9/247:30 am -
1 stop6h 05m
Deal found 8/11![United Airlines logo]()
$391
This Southwest deal was found by Cheapflights users on 8/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/111:10 pm -
Nonstop2h 50m
Sun 9/134:20 pm -
1 stop6h 20m
Deal found 8/10![Southwest logo]()
$375
This United Airlines deal was found by Cheapflights users on 8/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/107:30 am -
2 stops9h 08m
Mon 9/145:30 pm -
1 stop6h 40m
Deal found 8/10![United Airlines logo]()
$410
This Southwest deal was found by Cheapflights users on 8/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/181:30 pm -
2 stops9h 40m
Mon 9/213:45 pm -
1 stop5h 40m
Deal found 8/10![Southwest logo]()
$408
This Southwest deal was found by Cheapflights users on 8/6. 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 10/182:20 pm -
Nonstop2h 35m
Deal found 8/6![Southwest logo]()
$420
This Southwest deal was found by Cheapflights users on 8/7. 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 11/611:45 am -
2 stops8h 25m
Wed 11/188:25 am -
1 stop7h 25m
Deal found 8/7![Southwest logo]()
$420
This Southwest deal was found by Cheapflights users on 8/7. 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 9/135:30 am -
Nonstop2h 50m
Sat 9/194:15 pm -
Nonstop2h 40m
Deal found 8/7![Southwest logo]()
$420
This Southwest deal was found by Cheapflights users on 8/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/65:20 am -
Nonstop3h 05m
Sun 11/87:55 pm -
Nonstop2h 25m
Deal found 8/10![Southwest logo]()
$427
This Southwest deal was found by Cheapflights users on 8/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/75:50 am -
1 stop6h 45m
Tue 9/86:40 pm -
Nonstop2h 40m
Deal found 8/10![Southwest logo]()
$438
Last-minute flights from Boston to St. LouisDiscover last-minute flight deals from Boston to St. Louis. Data last updated August 11, 2026 and is based on user searches.
Discover last-minute flight deals from Boston to St. Louis. Data last updated August 11, 2026 and is based on user searches.
This Frontier deal was found by Cheapflights users on 8/9. 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.
Tue 8/1111:59 am -
1 stop6h 38m
Sun 8/166:34 pm -
1 stop12h 12m
Deal found 8/9![Frontier logo]()
$341
This Frontier deal was found by Cheapflights users on 8/6. 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 -
1 stop6h 38m
Sun 8/166:34 pm -
1 stop12h 12m
Deal found 8/6![Frontier logo]()
$340
This Kiwi.com deal was found by Cheapflights users on 8/9. 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 9/312:45 pm -
1 stop29h 37m
Mon 9/76:17 pm -
1 stop16h 30m
Deal found 8/9![Frontier logo]()
$339
This Southwest deal was found by Cheapflights users on 8/9. 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 9/35:50 am -
1 stop6h 45m
Sun 9/62:45 pm -
1 stop6h 45m
Deal found 8/9![Southwest logo]()
$343
This Southwest deal was found by Cheapflights users on 8/7. 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 9/55:50 am -
2 stops8h 35m
Sun 9/67:20 am -
1 stop6h 40m
Deal found 8/7![Southwest logo]()
$342
This Southwest deal was found by Cheapflights users on 8/8. 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 9/55:30 am -
Nonstop2h 50m
Sat 9/124:15 pm -
Nonstop2h 40m
Deal found 8/8![Southwest logo]()
$350
This Kiwi.com deal was found by Cheapflights users on 8/9. 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 9/1112:54 pm -
2 stops23h 38m
Mon 9/142:29 pm -
1 stop20h 38m
Deal found 8/9![Frontier logo]()
$347
This Southwest deal was found by Cheapflights users on 8/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/181:30 pm -
1 stop9h 30m
Mon 9/217:00 pm -
Nonstop2h 35m
Deal found 8/10![Southwest logo]()
$349
This Southwest deal was found by Cheapflights users on 8/9. 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 9/235:35 am -
Nonstop2h 50m
Sat 9/2611:45 am -
2 stops9h 00m
Deal found 8/9![Southwest logo]()
$345
This Kiwi.com deal was found by Cheapflights users on 8/9. 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 9/2412:54 pm -
2 stops23h 23m
Mon 9/282:29 pm -
1 stop20h 38m
Deal found 8/9![Frontier logo]()
$344
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 August 11, 2026.
Search for one-way flight options from Boston to St. Louis. Find affordable one-way fares based on user searches. Data last updated August 11, 2026.
This Frontier deal was found by Cheapflights users on 8/11. 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 9/1011:17 am -
1 stop7h 37m
Deal found 8/11![Frontier logo]()
$108
This Frontier deal was found by Cheapflights users on 8/11. 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.
Mon 11/910:11 am -
1 stop10h 28m
Deal found 8/11![Frontier logo]()
$114
This Kiwi.com deal was found by Cheapflights users on 8/11. 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.
Sun 10/119:15 am -
2 stops25h 25m
Deal found 8/11![Frontier logo]()
$122
This Frontier deal was found by Cheapflights users on 8/7. 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
Deal found 8/7![Frontier logo]()
$125
This Priceline deal was found by Cheapflights users on 8/11. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 11/1610:11 am -
1 stop10h 28m
Deal found 8/11![Frontier logo]()
$127
This Kiwi.com deal was found by Cheapflights users on 8/11. 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.
Sat 9/1212:54 pm -
2 stops24h 13m
Deal found 8/11![Frontier logo]()
$128
This Kiwi.com deal was found by Cheapflights users on 8/7. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/712:54 pm -
1 stop21h 46m
Deal found 8/7![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 August 11, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $339 (Kiwi.com) |
One-way from | $108 (Frontier) |
Popular in | July |
Cheapest in | January |
Average price | $464 |
Good round-trip deal | $376 or less |
Good one-way deal | $257 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 August 11, 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 Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Wed 11/11
1:10 pm-3:20 pm
Nonstop3h 10m
Lambert-St Louis
Thu 11/12
10:15 am-1:45 pm
Nonstop2h 30m
$369
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Fri 9/11
1:10 pm-3:00 pm
Nonstop2h 50m
Lambert-St Louis
Sun 9/13
4:20 pm-11:40 pm
1 stop6h 20m
$375
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Tue 9/22
9:00 am-3:38 pm
1 stop7h 38m
Lambert-St Louis
Thu 9/24
7:30 am-2:35 pm
1 stop6h 05m
$391
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Fri 9/18
1:30 pm-10:10 pm
2 stops9h 40m
Lambert-St Louis
Mon 9/21
3:45 pm-10:25 pm
1 stop5h 40m
$408
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Thu 9/10
7:30 am-3:38 pm
2 stops9h 08m
Lambert-St Louis
Mon 9/14
5:30 pm-1:10 am
1 stop6h 40m
$410
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Thu 10/8
5:25 am-7:25 am
Nonstop3h 00m
Lambert-St Louis
Sun 10/18
2:20 pm-5:55 pm
Nonstop2h 35m
$420
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Fri 11/6
11:45 am-7:10 pm
2 stops8h 25m
Lambert-St Louis
Wed 11/18
8:25 am-4:50 pm
1 stop7h 25m
$420
Quickest round-trip
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Sun 9/13
5:30 am-7:20 am
Nonstop2h 50m
Lambert-St Louis
Sat 9/19
4:15 pm-7:55 pm
Nonstop2h 40m
$420
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Fri 11/6
5:20 am-7:25 am
Nonstop3h 05m
Lambert-St Louis
Sun 11/8
7:55 pm-11:20 pm
Nonstop2h 25m
$427
BostonSt. Louis
BOS Boston Logan Intl - STL Lambert-St Louis
BOSSTL
Boston Logan Intl
Mon 9/7
5:50 am-11:35 am
1 stop6h 45m
Lambert-St Louis
Tue 9/8
6:40 pm-10:20 pm
Nonstop2h 40m
$438
Showing 1-10 of 22 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 August.
| 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
Airlines
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, January is the cheapest month in which you can book a flight from Boston to St. Louis (average of $408). Flying from Boston to St. Louis in July is currently the most expensive (average of $580). 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 August 11, 2026.
It’s typically best to fly out from Boston to St. Louis in the evening. Doing so could potentially save you 10% 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 August 8, 2026.
Travelers seeking maximum savings on their Boston to St. Louis flight should consider departing on Monday 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 144 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 16% 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 August 11, 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
Entertainment
7.5
Overall
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Entertainment
7.5
Overall
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Entertainment
7.5
Overall
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Entertainment
7.5
Overall
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Entertainment
7.5
Overall
8.0
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
8.0
ExcellentLibby,Jun 2026
TUS - LAS
Comfort
8.0
Entertainment
7.5
Overall
8.0
Food
7.0
Boarding
8.1
Crew
8.6
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
Fairview Heights
O'Fallon
Fenton
Swansea
Eureka
Maryland Heights
Collinsville
Wentzville
Glencoe
Chesterfield
Farmington
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Top 5 airlines flying from Boston to St. Louis
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| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$90 | Average$255 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$148 | Average$618 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$302 | Average$512 | FlexibilityNo cancel fee | On-time71% | |
| Cheapest$327 | Average$437 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$337 | Average$509 | FlexibilityNo cancel fee | On-time63% |