A city skyline with a prominent arch bridge at sunset.

$109 Cheap Flights from Boston (BOS) to St. Louis (STL)

View $109 flight on Thu, Sep 10, 2026Opens in a new window

Popular airlines from Logan International Airport (BOS) to St. Louis Lambert Intl. Airport (STL)

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Cheap Flights from Boston to St. Louis (BOS-STL)

Prices were available within the past 7 days and start at $109 for one-way flights and $228 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Sat, Oct 24 - Sat, Oct 31
BOS
Boston
STL
St. Louis
$228 Roundtrip, found 4 hours ago
$228
Roundtrip
found 4 hours ago
Select Frontier Airlines flight, departing Sat, Oct 24 from Boston to St. Louis, returning Sat, Oct 31, priced at $228 found 4 hours ago
Frontier Airlines
Sat, Oct 24 - Fri, Oct 30
BOS
Boston
STL
St. Louis
$238 Roundtrip, found 6 hours ago
$238
Roundtrip
found 6 hours ago
Select Frontier Airlines flight, departing Sat, Oct 24 from Boston to St. Louis, returning Fri, Oct 30, priced at $238 found 6 hours ago
Frontier Airlines
Thu, Oct 22 - Sat, Oct 31
BOS
Boston
STL
St. Louis
$248 Roundtrip, just found
$248
Roundtrip
just found
Select Frontier Airlines flight, departing Thu, Oct 22 from Boston to St. Louis, returning Sat, Oct 31, priced at $248 just found
Frontier Airlines
Thu, Sep 10 - Sat, Sep 19
BOS
Boston
STL
St. Louis
$258 Roundtrip, just found
$258
Roundtrip
just found
Select Frontier Airlines flight, departing Thu, Sep 10 from Boston to St. Louis, returning Sat, Sep 19, priced at $258 just found
Frontier Airlines
Thu, Oct 22 - Fri, Oct 30
BOS
Boston
STL
St. Louis
$258 Roundtrip, found 2 hours ago
$258
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Thu, Oct 22 from Boston to St. Louis, returning Fri, Oct 30, priced at $258 found 2 hours ago
Frontier Airlines
Fri, Oct 30 - Sat, Nov 7
BOS
Boston
STL
St. Louis
$262 Roundtrip, found 2 hours ago
$262
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Fri, Oct 30 from Boston to St. Louis, returning Sat, Nov 7, priced at $262 found 2 hours ago
American Airlines
Thu, Nov 5 - Sat, Nov 7
BOS
Boston
STL
St. Louis
$278 Roundtrip, found 4 hours ago
$278
Roundtrip
found 4 hours ago
Select American Airlines flight, departing Thu, Nov 5 from Boston to St. Louis, returning Sat, Nov 7, priced at $278 found 4 hours ago
Delta
Fri, Oct 30 - Sat, Nov 7
BOS
Boston
STL
St. Louis
$292 Roundtrip, found 2 hours ago
$292
Roundtrip
found 2 hours ago
Select Delta flight, departing Fri, Oct 30 from Boston to St. Louis, returning Sat, Nov 7, priced at $292 found 2 hours ago
Southwest Airlines
Wed, Nov 4 - Fri, Nov 6
BOS
Boston
STL
St. Louis
$294 Roundtrip, found 10 hours ago
$294
Roundtrip
found 10 hours ago
Select Southwest Airlines flight, departing Wed, Nov 4 from Boston to St. Louis, returning Fri, Nov 6, priced at $294 found 10 hours ago
United
Sat, Sep 26 - Mon, Oct 5
BOS
Boston
STL
St. Louis
$312 Roundtrip, just found
$312
Roundtrip
just found
Select United flight, departing Sat, Sep 26 from Boston to St. Louis, returning Mon, Oct 5, priced at $312 just found

Alternative airports near St. Louis

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Lambert-St. Louis Intl. STL. Cheapest option available. Average driving time to city center is 20 minutes. Flights from $435
STL
Lambert-St. Louis Intl.
Cheapest
Average driving time to city center20 min
Flights from $435

What you need to know for your flight from Logan Intl. to Lambert-St. Louis Intl.

Boston (BOS) to St. Louis (STL) at a glance

Travel from Boston (BOS) to St. Louis (STL) with a variety of airlines on this domestic short-haul route. Explore options for cheap flights from Boston, including both full-service and low-cost carriers, to find the itinerary that aligns with your budget and travel plans. As you prepare to discover the iconic sights and vibrant neighborhoods of St. Louis, review the essential details for flights from Logan International Airport to Lambert-St. Louis International Airport.

  • Fastest flight duration: around 3h 15m non-stop
  • Route distance: roughly 1,000 miles (1,610 km)
  • Flights per week: around 25+ flights with multiple daily departures on average
  • Typical fares (one-way): economy tickets often range from $120–$500, depending on seasonality and how far ahead you book

Flights from Logan International Airport (BOS) to Lambert-St. Louis International Airport (STL)

According to recent traveler bookings, the top airlines flying from Boston to St. Louis include both non-stop and one-stop options, with notable layovers at O'Hare International Airport (ORD) with a layover of approximately 1 hour and 15 minutes, Detroit Metropolitan Wayne County Airport (DTW) at around 1 hour, and LaGuardia Airport (LGA) with a 1 hour and 30 minute layover. This variety allows you to mix and match factors such as price, total travel time, and cabin class to discover the ideal itinerary for your trip.

  • American Airlines: This full-service airline provides various travel options, including non-stop, one-stop, and multi-stop flights. One-way fares generally range from $145 to $500, making up about 47% of departures on this route, with a typical non-stop flight duration of 3 hours and 15 minutes.
  • Southwest Airlines: A budget-friendly carrier, Southwest offers both non-stop and one-stop flights. One-way ticket prices usually fall between $140 and $500, representing around 37% of all departures on this route, with a standard non-stop flight time of 3 hours and 15 minutes.
  • Delta: As a full-service airline, Delta provides one-stop services with one-way fares typically ranging from $120 to $510. It accounts for approximately 9% of departures on this route, featuring an in-flight duration of 4 hours and 15 minutes and a total travel time of about 5 hours and 30 minutes, including layovers.
  • United: This full-service airline also offers one-stop connections, with one-way ticket prices ranging from $120 to $505. United comprises roughly 6% of departures on this route, boasting an in-flight time of 4 hours and 15 minutes and a total journey time of around 5 hours and 30 minutes, including layovers.
  • Frontier Airlines: A low-cost option, Frontier provides one-stop service with one-way fares typically priced between $120 and $240. It represents about 1% of departures on this route, featuring an in-flight duration of 4 hours and 15 minutes and a total travel time of roughly 5 hours and 30 minutes, including layovers.

Travelers flying from Boston to St. Louis can enhance their experience by upgrading to first class with American Airlines, which provides exceptional service on this route.

Best time to fly from Boston (BOS) to St. Louis (STL)

The most popular months for travelers flying from Boston to St. Louis are March, April, and October, when peak temperatures in St. Louis reach up to 58.6°F in October. If you prefer quieter travel, consider July, the least busy and relatively cheaper time to visit with fewer crowds and temperatures around 78.6°F. For better deals, August usually offers the lowest average one-way fare around $248. Flight availability peaks in October, with approximately 36 flights per week, making it easier to find convenient departure times. January has the fewest flights, with approximately 18 flights per week.

  • Cheapest time to fly: August usually offers good deals with average one-way fare around $248, roughly 9% cheaper than the yearly average.
  • More budget-friendly months to fly: May, September, and July typically offer average one-way fares roughly ranging from $251 to $271.
  • Most flight options: October has the highest number of flights from Boston to St. Louis, with approximately 36 flights per week, giving you more flexibility in scheduling your trip.
calendar iconMonthtemperature iconTemperaturecrowd level iconDemandflights iconWeekly Flightsprice iconAverage one-way Fare
January31.6°F (-0.2°C)Average18$280
February34.9°F (1.6°C)Average19$294
March46.4°F (8.0°C)High25$292
April56.1°F (13.4°C)High31$285
May66.6°F (19.2°C)Average31$251
June76.1°F (24.5°C)Low28$272
July78.6°F (25.9°C)Low28$271
August77.0°F (25.0°C)Average33$248
September70.9°F (21.6°C)Average34$253
October58.6°F (14.8°C)High36$281
November46.2°F (7.9°C)Average33$278
December37.8°F (3.2°C)Low26$282

*Average one-way fare is based on Expedia flight booking data from January 2025 to April 2026 for the specified route and travel class and may change depending on availability, dates, and demand.

Alternative route from Boston (BOS) to St. Louis (STL)

  • Boston to Springfield (BOS-SPI): Abraham Lincoln Capital Airport (SPI) is approximately 85 miles from Lambert-St. Louis International Airport (STL). One-way economy ticket prices for this route generally fall between $230 and $500, varying by season and the timing of your booking. Usually, this route features one-stop flights, primarily connecting through O'Hare International Airport (ORD). The leading airline operating on this route is American Airlines.

How to find the best prices for flights from Boston (BOS) to St. Louis (STL)

Getting some of the best deals on flights from Boston to St. Louis is all about timing and flexibility. Here are some key tips to help you save:

  1. Best times to book and fly: cheaper fares are usually available when booking at least two months in advance, although most travelers tend to book between two to eight weeks ahead. Morning flights, from 5 AM to 12 PM, not only offer lower prices but are also the most popular. Additionally, flying on Wednesday is typically cheaper, while Thursday remains the most favored travel day.
  2. Set up price alerts: stay updated on price changes by using Expedia's Price Tracker. Receive alerts when fares drop for your selected route.
  3. Bundle and save: bundle your flight and hotel to save on Expedia, or unlock a hotel deal after booking your flight.*
  4. Compare flight options: use Expedia's search tool to compare airlines, routes, direct vs. non-direct flights, and flight times. You can also sort by price to find the most affordable options.
  5. Stay flexible with dates: being open to different travel days can sometimes help you find better prices on flights and hotels.
  6. Think about luggage: nowadays, it's important to check the airline's baggage policies to find the best value. That may be paying for an additional carry-on bag or booking a ticket with checked luggage included. Either way, double-check your allowance before confirming your booking to avoid excess baggage fees at the airport.

*Members only. Savings vary and are not available on all bundles. Select hotels.

Arriving at Lambert-St. Louis International Airport from Logan International Airport

St. Louis welcomes travelers from Boston with a range of transport options based on price, convenience, and proximity. Here's how to reach St. Louis efficiently:

  • Hotel transfer: Transfers offer a convenient way to reach your hotel in St. Louis, with private rides that can be arranged in advance.
  • Car rental: Renting a car from Lambert-St. Louis International Airport is a great option if you plan to explore and sightsee beyond the city. Browse cheap car rentals at Lambert-St. Louis International Airport on Expedia.
  • Taxi/ride-hailing: Taxis and ride-hailing services may be available from designated pickup areas outside the terminal, check locally on arrival.
  • Public transportation: From Lambert-St. Louis International Airport, Lambert Main Terminal Station, a metro station, is located about 0.1 miles away on foot, providing convenient access for travelers.

Frequently asked questions

How much does a flight from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) cost?
You can find cheap one-way flights from $109 and cheap return flights from $228 Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) with Expedia. One-way flights typically cost between $186 and $920, and return flights often range between $396 and $1586. Flight prices vary based on the month and day of the week you want to travel, as well as the airline and how far in advance you book your ticket. Filter your search on Expedia by "Price (lowest to highest)" to see the cheapest fares first, and use the Price Tracking tool to receive alerts when Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) ticket fares go up or down.*Typical price ranges based on flights available on Expedia in the last year. Prices include multi-airline options.
What is the cheapest month to fly from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
September is the cheapest month to fly from Boston (BOS) to St. Louis (STL), with average round-trip fares around $394. This is about 11% lower than the average price throughout the year, as September usually sees a decline in travel demand after the summer. Other economical months to consider are February and August.*Averages based on flights available on Expedia in the last year.
Which airlines fly direct from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
American Airlines offers around 18 weekly direct flights from BOS to STL.
What is the cheapest airline that flies from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Southwest Airlines is one of the cheapest airlines offering nonstop flights from Boston (BOS) to St. Louis (STL), with round-trip tickets starting from around $191. This is a great option if you're looking for a direct route. Use Expedia's search tool to compare the prices and schedules of airlines that fly this route to find the best option for your plans and budget.*Prices based on flights available on Expedia in the last year.
How do I find cheap flights from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
To find a cheap flight from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.), be flexible with your dates. Traveling outside of peak vacation months and booking a mid-week flight can help you save. Early morning and late night flights are often more affordable, too. Expedia allows you to compare flight times, airlines and routes all in one place to find low fares. You can also set up Price Tracking and receive alerts when fares go up or down.
What is the best airline to fly with from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The best airline to fly with from Boston, MA (BOS) to St. Louis, MO (STL) will differ from traveler to traveler. If you like to fly early, American Airlines offers early morning flights. If price is the most important factor, American Airlines typically offers the lowest fares. American Airlines offers the most daily flights from Boston to St. Louis, which is great if flexibility is what you value most. The best carrier for this journey could also be the one you have a loyalty membership with, as flying with that airline or another airline within the same alliance could help you collect points or enjoy lounge access.
What is the best time to fly from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
When flying from Boston, MA (BOS) to St. Louis, MO (STL), consider traveling in September or August. These months are not only the cheapest, with average return flight prices around $394, but they also provide a good mix of favorable weather and travel options. August is great for summer activities, while September offers a more relaxed atmosphere.*Prices based on flights available on Expedia in the last year.
How many flights per day from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
On average, there are around 5 nonstop flights per day from Logan Intl. (BOS) to Lambert-St. Louis Intl. (STL). For more options, look at flights that include layovers.
What is the earliest flight from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The earliest flight from Boston (Logan International) to St. Louis (Lambert-St. Louis International) usually departs at around 5:00 AM. This seasonal service is offered by American Airlines and Southern Airways Express, allowing you to arrive in St. Louis early and start your day. To compare early flights on Expedia, select the "Early Morning" and "Morning" filters in your search.
What are the most popular departure times for flights from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
The most popular departure times for flights from Boston (BOS) to St. Louis (STL) are in the early morning, from 6am to 9am. This time window accounts for about 27% of total traffic. Major carriers like American Airlines and Delta operate during this time, making it a great option for travelers looking to arrive in St. Louis early in the day.
How long does it take to fly from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
Direct flights from BOS to STL usually take about 3 hours 20 minutes, traveling roughly 1,044 miles. If you opt for a connecting flight, expect to add around 2 hours 30 minutes to your journey. Keep in mind that actual flight times can vary due to wind patterns, weather, and air traffic.
Can you fly business or first class from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
First class seats are offered on the BOS to STL route. First class cabins are available on:

  • Delta Air Lines
  • American Airlines
  • United Airlines
  • Spirit Airlines

How much is a business class flight from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
A direct, return business class ticket from Boston (BOS) to St. Louis (STL) typically costs between $1,061 - $1,574. A non-stop, one-way business class flight is usually around $532 - $1,032. You may also be able to find a cheaper business class journey between Boston to St. Prices often fluctuate based on seasonality and how early you book. You may also be able to find a cheaper business class journey between Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) if you opt for a connecting flight.*Prices based on flights available on Expedia in the last year.
How do I earn miles on a Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight with Expedia?
It's easy to earn miles on a Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight when you book with Expedia. Before you confirm your booking, simply select your frequent flyer program and enter your program number. As a member of One Key™, you can also earn OneKeyCash™* on top of your airline miles when you book with Expedia.*Excludes taxes and fees. OneKeyCash is not redeemable for cash and can only be used on Expedia and other participating brands.
What airports do you fly into for St. Louis from Logan Intl. (BOS)?
From Logan Intl. (BOS), you can fly into Lambert-St. Louis Intl. (STL) to reach St. Louis. Some flights may connect through major hubs like Portland Intl. (PDX), Baltimore Washington Intl. Thurgood Marshall (BWI), Nashville Intl. (BNA) before reaching St. Louis. Compare routes and airports on Expedia to find the best flight options for your travel plans.
Is it cheaper to buy a plane ticket from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) at the last minute?
Typically, booking a last minute flight from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) will be more expensive than booking in advance. As the departure date approaches, there are usually fewer seats available which can drive up the cost. However, if there's some wiggle room with your travel dates and times, you could bag a cheap last-minute fare.
Is it cheaper to book a Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight and hotel package?
Securing a Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) St Louis Vacation Packages is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your travels all in one place. Select from our extensive range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.)?
If you booked your Boston, MA (BOS-Logan Intl.) to St. Louis, MO (STL-Lambert-St. Louis Intl.) flight within the last 24 hours, you may be able to modify or cancel it without any fees. Depending on the airline and the type of ticket you have, additional charges may apply for changes beyond this timeframe. Airline policies and contact information can be found in your itinerary or confirmation email. Or, head to our Customer Service portal if you'd like more information.

Travel information

Origin airport
Logan Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Alaska Airlines, American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Roundtrip price
$228
Distance
1043 mi
Average flight time
1 hour 51 mins

Book with confidence

Boston to St. Louis Flights

The cheapest times to fly from Boston to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Boston to St. Louis are during the month of October. You can find some of the cheapest flights from Boston to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Boston to St. Louis

Sunday is one of the best days to book for cheap flights from Boston to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Boston to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Boston to St. Louis in 2026. You can also book with separate airlines for your outbound and return journeys, from $109 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Boston to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Boston to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Boston to St. Louis Flights

*Flight schedules are subject to change.

*Available to One Key members.

 

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