$663 Cheap Flights from St. Louis (STL) to Buenos Aires (AEP)

View $663 flight on Thu, Oct 1, 2026Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Buenos Aires (AEP-Aeroparque Jorge Newbery)

Cheap Flights from St. Louis to Buenos Aires (STL-AEP)

Prices were available within the past 7 days and start at $663 for one-way flights and $966 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

LATAM Airlines Group
Tue, Mar 10 - Wed, Mar 25
STL
St. Louis
AEP
Buenos Aires
$966 Roundtrip, found 3 days ago
$966
Roundtrip
found 3 days ago
Select LATAM Airlines Group flight, departing Tue, Mar 10 from St. Louis to Buenos Aires, returning Wed, Mar 25, priced at $966 found 3 days ago
LATAM Airlines Group
Tue, Mar 10 - Wed, Mar 25
STL
St. Louis
AEP
Buenos Aires
$973 Roundtrip, found 3 days ago
$973
Roundtrip
found 3 days ago
Select LATAM Airlines Group flight, departing Tue, Mar 10 from St. Louis to Buenos Aires, returning Wed, Mar 25, priced at $973 found 3 days ago
LATAM Airlines Group
Mon, Jul 13 - Thu, Jul 30
STL
St. Louis
AEP
Buenos Aires
$1,056 Roundtrip, found 1 day ago
$1,056
Roundtrip
found 1 day ago
Select LATAM Airlines Group flight, departing Mon, Jul 13 from St. Louis to Buenos Aires, returning Thu, Jul 30, priced at $1,056 found 1 day ago
Delta
Sun, May 3 - Sun, May 24
STL
St. Louis
AEP
Buenos Aires
$1,091 Roundtrip, found 4 days ago
$1,091
Roundtrip
found 4 days ago
Select Delta flight, departing Sun, May 3 from St. Louis to Buenos Aires, returning Sun, May 24, priced at $1,091 found 4 days ago
LATAM Airlines Group
Thu, Mar 5 - Fri, Mar 20
STL
St. Louis
AEP
Buenos Aires
$1,096 Roundtrip, found 1 day ago
$1,096
Roundtrip
found 1 day ago
Select LATAM Airlines Group flight, departing Thu, Mar 5 from St. Louis to Buenos Aires, returning Fri, Mar 20, priced at $1,096 found 1 day ago
LATAM Airlines Group
Sun, May 24 - Sun, May 31
STL
St. Louis
AEP
Buenos Aires
$1,104 Roundtrip, found 5 days ago
$1,104
Roundtrip
found 5 days ago
Select LATAM Airlines Group flight, departing Sun, May 24 from St. Louis to Buenos Aires, returning Sun, May 31, priced at $1,104 found 5 days ago
LATAM Airlines Group
Wed, Mar 18 - Sun, Mar 22
STL
St. Louis
AEP
Buenos Aires
$1,132 Roundtrip, found 2 days ago
$1,132
Roundtrip
found 2 days ago
Select LATAM Airlines Group flight, departing Wed, Mar 18 from St. Louis to Buenos Aires, returning Sun, Mar 22, priced at $1,132 found 2 days ago
LATAM Airlines Group
Tue, Mar 10 - Wed, Mar 25
STL
St. Louis
AEP
Buenos Aires
$1,136 Roundtrip, found 3 days ago
$1,136
Roundtrip
found 3 days ago
Select LATAM Airlines Group flight, departing Tue, Mar 10 from St. Louis to Buenos Aires, returning Wed, Mar 25, priced at $1,136 found 3 days ago
LATAM Airlines Group
Thu, Apr 23 - Mon, Apr 27
STL
St. Louis
AEP
Buenos Aires
$1,140 Roundtrip, found 3 days ago
$1,140
Roundtrip
found 3 days ago
Select LATAM Airlines Group flight, departing Thu, Apr 23 from St. Louis to Buenos Aires, returning Mon, Apr 27, priced at $1,140 found 3 days ago
Air Canada
Sat, May 2 - Sat, May 16
STL
St. Louis
AEP
Buenos Aires
$1,834 Roundtrip, found 5 hours ago
$1,834
Roundtrip
found 5 hours ago
Select Air Canada flight, departing Sat, May 2 from St. Louis to Buenos Aires, returning Sat, May 16, priced at $1,834 found 5 hours ago

Alternative airports near Buenos Aires

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

Select flight to Ministro Pistarini Intl. EZE. Cheapest option available. Average driving time to city center is 25 minutes. Flights from $1,533
EZE
Ministro Pistarini Intl.
Cheapest
Average driving time to city center25 min
Flights from $1,533

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP) cost?
Secure a cheap one-way flight from $663 or cheap return flight from $966 from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight deals on this route.
What is the cheapest month to fly from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP)?
The cheapest month to fly from STL to AEP is March, when there's less demand. Off-peak season is often when airlines offer better prices between these airports.
What is the cheapest airline that flies from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP)?
Expedia's filter tool lets you easily compare different airlines, travel time and fares all in one place. Select your preferences, then sort by "Price (lowest to highest)" to find out which carrier offers the cheapest STL to AEP flight.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP)?
Nonstop flights from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP) aren't available daily, so you'll have to take a flight with a layover. Explore your options with Expedia's filter tool. Enter your dates and click on either "1 Stop" or "2+ Stops."
What day of the week has the most flights from STL to AEP?
You'll generally find Tuesday the quietest day for flights, while Fridays are often the busiest.* However this can vary from season to season and during peak travel times or public holidays.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP)?
To avoid possible delays on the Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP) route, aim to fly before 3 PM. Flights after this time have a 22% higher chance of cancellation.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP) last-minute?
Booking your flight from STL to AEP right before your journey is typically more expensive. However, if there's some wiggle room with your travel dates and times, you could land a cheap last-minute fare.
Is it cheaper to book a STL to AEP flight and hotel package?
Compared with arranging hotels and flights separately, booking a STL to AEP flight and hotel package with Expedia could result in significant savings. Better yet, having it all in one place will take the stress out of travel planning. Just pick your flights and select from our wide range of hotels, then customize your trip with other add-ons like activities and car rentals.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Aeroparque Jorge Newbery Airport (AEP)?
It's usually possible to reschedule or cancel your STL to AEP flight. However, if the booking was made more than 24 hours ago, additional fees may apply. Refer to your airline's policies in your itinerary to see what changes are allowed and whether any costs are involved. You'll also find more information on our Customer Service portal.

Travel information

Origin airport
Lambert-St. Louis Intl.
Destination airport
Aeroparque Jorge Newbery
Airlines serving
Air Canada, LATAM Airlines Group
Roundtrip price
$965
Distance
5461 mi

Book with confidence

St. Louis to Buenos Aires Flights

The cheapest times to fly from St. Louis to Buenos Aires

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 St. Louis to Buenos Aires are during the month of March. You can find some of the cheapest flights from St. Louis to Buenos Aires with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to Buenos Aires

Sunday is one of the best days to book for cheap flights from St. Louis to Buenos Aires: 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 St. Louis to Buenos Aires

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 St. Louis to Buenos Aires in 2026. You can also book with separate airlines for your outbound and return journeys, from $663 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 St. Louis to Buenos Aires 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 St. Louis to Buenos Aires 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.

 

St. Louis to Buenos Aires Flights

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*Available to One Key members.