STL - BUE

$431 Find Cheap Flights from St. Louis to Buenos Aires

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Buenos Aires departing on 2/20. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Buenos Aires

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Buenos Aires, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Buenos Aires, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$1,026
United Airlines
Mon 1/19Mon 1/26
STL - EZE • 1 stop
Cheapest one-way
$431
Multiple Airlines
Fri 2/20
STL - AEP • 3 stops
When to travel
September
Cheapest • 17% price drop
December
Most popular
Good to know
Good to know
+1
+1
Good to know
Good to know
+1
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KAYAK searches 100s of sites at once to find you the best travel deals.
We hope you love your trip to Buenos Aires!
Flight Deals
Booking Insights
Flight Deals

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

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Buenos Aires that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from St. Louis to Buenos Aires

Mon, Jan 19 - Mon, Jan 26
United Airlines Logo
4:35 pm - 9:20 amSTL-EZE
13h 45m1 stop
United Airlines Logo
10:05 pm - 9:22 amEZE-STL
14h 17m1 stop
$1,026United Airlines
Find Deal
Sun, Mar 8 - Tue, Mar 17
LATAM Airlines Logo
4:00 pm - 9:35 amSTL-EZE
15h 35m2 stops
LATAM Airlines Logo
8:00 am - 9:04 amEZE-STL
27h 04m2 stops
$1,048LATAM Airlines
Find Deal
Sun, Mar 8 - Tue, Mar 17
LATAM Airlines Logo
7:05 pm - 5:00 pmSTL-AEP
19h 55m2 stops
LATAM Airlines Logo
5:15 pm - 11:50 amAEP-STL
20h 35m2 stops
$1,058LATAM Airlines
Find Deal
Sun, Mar 8 - Tue, Mar 17
LATAM Airlines Logo
6:00 am - 7:20 amSTL-EZE
23h 20m1 stop
LATAM Airlines Logo
8:55 pm - 9:04 amEZE-STL
14h 09m1 stop
$1,058LATAM Airlines
Find Deal
Sat, Jan 17 - Sun, Jan 25
LATAM Airlines Logo
5:00 pm - 6:40 pmSTL-AEP
22h 40m2 stops
LATAM Airlines Logo
3:40 pm - 11:04 amAEP-STL
22h 24m2 stops
$1,098LATAM Airlines
Find Deal
Sat, Jan 17 - Sun, Jan 25
LATAM Airlines Logo
12:00 pm - 10:15 amSTL-EZE
19h 15m2 stops
LATAM Airlines Logo
11:00 am - 11:37 pmEZE-STL
15h 37m2 stops
$1,102LATAM Airlines
Find Deal
Sat, Jan 17 - Sun, Jan 25
American Airlines Logo
10:00 am - 7:10 amSTL-EZE
18h 10m1 stop
American Airlines Logo
10:25 pm - 4:14 pmEZE-STL
20h 49m1 stop
$1,106American Airlines
Find Deal
Sun, Feb 1 - Sat, Feb 7
United Airlines Logo
6:40 pm - 7:20 amSTL-EZE
33h 40m2 stops
United Airlines Logo
10:05 pm - 9:22 amEZE-STL
14h 17m1 stop
$1,146United Airlines
Find Deal
Sun, Feb 1 - Sat, Feb 7
LATAM Airlines Logo
3:45 pm - 9:00 amSTL-EZE
14h 15m1 stop
LATAM Airlines Logo
8:55 pm - 11:54 amEZE-STL
17h 59m1 stop
$1,174LATAM Airlines
Find Deal
Thu, Dec 11 - Sat, Dec 20
Multiple Airlines Logo
2:47 pm - 4:35 amSTL-EZE
34h 48m3 stops
Multiple Airlines Logo
5:35 am - 10:56 amEZE-STL
32h 21m3 stops
$1,182Multiple Airlines
Find Deal
Booking Insights

KAYAK's insights & trends for St. Louis to Buenos Aires flights

Get data-powered insights and trends into flights from St. Louis to Buenos Aires to help you find the cheapest flights, the best time to fly and much more.

How much is a round-trip flight from St. Louis to Buenos Aires?

This analysis is based on the cheapest round-trip price found on KAYAK in the last 12 months by searching for a flight from St. Louis to Buenos Aires departing in January.

What’s the cheapest day of the week to fly from St. Louis to Buenos Aires?

The average price of all round-trip flights from St. Louis to Buenos Aires clicked on KAYAK for each day over the last 12 months.

Your flight ticket price will generally be cheaper if you fly to Buenos Aires on a Tuesday and more expensive on a Wednesday. On your return trip to St. Louis, you should consider flying back on a Monday, and avoid Sundays for better deals.

What is the cheapest month to fly from St. Louis to Buenos Aires?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to Buenos Aires, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from St. Louis to Buenos Aires is September, where tickets cost $1,056 (return) on average. On the other hand, the most expensive months are August and January, where the average cost of round-trip tickets is $1,423 and $1,406 respectively.

Good to know

Low seasonFebruary
Cheapest flight$431
Best time to beat the crowds but there is an average 4% increase in price.
Most popular time to fly with an average 4% increase in price.
Flight from St. Louis to Buenos Aires

When to book flights from St. Louis to Buenos Aires

Are your dates flexible? Find out the best times to travel from St. Louis to Buenos Aires based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from St. Louis to Buenos Aires

  • What is the cheapest flight from St. Louis to Buenos Aires?

    In the last 3 days, the lowest price for a flight from St. Louis to Buenos Aires was $431 for a one-way ticket and $1,026 for a round-trip.

  • Do I need a passport to fly between St. Louis and Buenos Aires?

    A passport is required to fly from St. Louis to Buenos Aires.

  • Which airports will I be using when flying from St. Louis to Buenos Aires?

    St. Louis is served by only 1 airport and there are 2 airports in Buenos Aires. You will leave St. Louis from Lambert-St Louis and you will be arriving in Buenos Aires at one of these airports: Buenos Aires Jorge Newbery or Buenos Aires Ministro Pistarini.

  • Which aircraft models fly most regularly from St. Louis to Buenos Aires?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from St. Louis to Buenos Aires?

    Star Alliance, oneworld, and SkyTeam are the airline alliances operating flights between St. Louis and Buenos Aires, with Star Alliance being the most commonly used for this route.

  • Which is the best airline for flights from St. Louis to Buenos Aires, Delta or LATAM Airlines?

    The two airlines most popular with KAYAK users for flights from St. Louis to Buenos Aires are Delta and LATAM Airlines. With an average price for the route of $1,267 and an overall rating of 7.9, Delta is the most popular choice. LATAM Airlines is also a great choice for the route, with an average price of $1,105 and an overall rating of 7.5.

  • How does KAYAK find such low prices on flights from St. Louis to Buenos Aires?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from St. Louis to Buenos Aires.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from St. Louis to Buenos Aires?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Buenos Aires from St. Louis is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from St. Louis to Buenos Aires?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Buenos Aires with an airline and back to St. Louis with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from St. Louis to Buenos Aires?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Buenos Aires from St. Louis up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 4 airlines serving from St. Louis to Buenos Aires

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to Buenos Aires. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from St. Louis to Buenos Aires? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
DeltaOverall score based on 8002 reviews
7.9Entertainment
7.3Food
8.1Boarding
8.5Crew
7.9Comfort
Airline reviews

Great. Seamless. Check in agent at kiosk international was amazing and extremely helpful.

10.0 ExcellentWilliam, Nov 2025ATL - SJO
Read more Delta reviews

Great. Seamless. Check in agent at kiosk international was amazing and extremely helpful.

Our flight from SFO to MSP was right on time on 11/15/2025. No delays. As we approached MSP at about 8 pm, we circled in the air until 8:40 pm so I don't call that efficient for MSP. I think the captain should announce the delay and why. (as if we all don't know that we are just circling around the area, slowing down, speeding up, slowing down.) Thank you. Marilyn Fischer

Service in business class was not impressive. I ordered coffee with dinner and then watched other people get 2 refills before I got my 1 cup of coffee, and only after I pressed the attendant button overhead. Furthermore, the seats in the forward cabin need maintenance on this 737-800: the upholstery is detaching from the seat frame, at least on the backs of seats 1C, 1D.

Plenty of leg room, temperature was great and staff was excellent. Would do it more often.

The ticket agents in West Palm Beach on Friday afternoon Nov. 7th were incredible in getting us on an earlier plane to Atlanta during the government shutdown. Had the taken our original flight we would have missed our connection. She did this on her own, We didn't even have to ask, and she did it all with a smile and showing genuine concern that we would be taken care of. We are very grateful and thankful. We fly often, and now we will be sure to fly Delta.

Flight delayed then cancelled. Misplaced luggage. Still do not have. Rented car 1100 mile drive. I had to buy some overnight Hotels clothes toiletries gas food at my expense. Still not home. Not sure where luggage is. Over 4 hours on hold to Felta

I truly love flying with Delta. They have always treated me with the upmost respect

Our flight attendant in FIRST CLASS was one of the worst I’ve ever had. She was not at all pleasant, nor particularly good at her service.

Everything went well and was good. Nothing exceptional, but no complaints either. Cheap seats are pretty comfortable.

Staff were friendly and happy. Delta could make sure passengers that don't have the app know of changes. Without Kayak I would not have known about the change of gate or the delay. Kayak was faster to notify me.

Latam may be the worst airline in the world, far worse than even the lowest of low cost airlines in the USA. I wasted hours trying to PAY THEM TO CHECK A BAG! Then they misled me at the terminal, sent me through the wrong security line, the list goes on and on... Just absolutely terrible in every way. Avoid at all costs.

The plane broke down at the Lima stopover and they offered to put me on a flight the be t day but I had to be back in LA that morning and so I had to buy another ticket from Avianca and United for $2k I asked LATAM for compensation and received none. Very bad experience

Really bad experience – delayed for 6 hours without any notice, no food or drinks provided, and stuck in the horrible Cartagena airport.

The flight was late. Please do not delay next time.

I couldn't travel, now I can't get a refund and to change the date I have to pay an absurd fine.

My biggest complaint is the comfort. I am not tall and there was no legroom. It was very uncomfortable. During my transfer in Sao Paola, the flight was slightly delayed so boarding was confusing because there were no instructions in English.

I never got this flight. You sent me to Chile!!! And from Chile I got the other flight to São Paulo... I've arrived 7h latter than I was supposed to arrive because of Delta delays.

Because the flight was late, we lost the connection to Brazil. You, Delta delayed, and you Delta anticipated the door closing in 15 min from Miami to GRU. Why? It caused a lot of stress! I almost could not see my mother in law alive because of your delay.

Boarding was done by woman who insisted on strict standing in line policy; food was ok; entertainment minimal

Wider seats, better seat cushions, (I felt like there was a board I was sitting on). I had the chicken to eat but It neither tasted nor looked like chicken. The fruit was good.

Very thoughtful flight attendant offered me water immediately since I had run to make my connection.

Door to door, the crew and staff were amazing. It was a stressful travel day with delays, but they were focused on customers and doing what they could to get us to our destinations.

Even though we were delayed, we were able to make our connection

Seats in waiting area and on plane hard as rock. Fast internet on the flight was great! Crew was kind.

Starlink wifi on the Embraer E175 is an excellent experience. I was able to connect and work from IAD all the way to approach into BTV.

Older aircraft, no meal, only food was for purchase. Not impressed United.

United needs to step up their game. Delayed flight leaving Seattle, San Francisco. Older aircraft, not very comfortable.

Always wish for more healthy, gluten free options. We have to bring our own.

Having a long layover, I was very appreciative of the ability to stand by for an earlier flight. Other airlines like Delta have refused this to me in the past, just to be mean (because my ticket class wasn't high enough). United went out of their way to help me get to my destination early, which I really appreciated given that it was the third leg of a 24+ hour journey for me.

Other than a way way too cold cabinets for the entire flight, all was great

We were told the flight was delayed 5 times, then it was moved to the next day.

More choices on snacks. Built-in video screen to enjoy entertainment choices.

we landed at cmh ten minutes early but had to sit on tarmac for twenty minutes because a plane was at our gate despite the fact that 3 other gates were open.

The experience with American Airlines was good, although the Philippines Airlines flight was much better (better seats, better food, better entertainment options, overall better). Again, the MIA to LAX flight was fine, but nothing in comparison to the comfort and accommodations of the Philippines Airlines flight from LAX to MNL.

I have a gluten allergy so did have any food

I have a gluten allergy so didn't have any food

Loved the crew . Absolutely no complaints. Except for luggage lost

Everything was good The connects, with no blame to crew. Or pilots. I understand they are short staffed. Everything went well for me. I'll be using you guys again in May if not sooner.

this plane was really old, had exit row seats and tray was in arm of seat so super uncomfortable to use. another seat they could t even use the tray it was broke. seat i. front of me had duct tape on it cause seat was ripped open... this plane should either be updated or retired.

We were very rushed by a staff member at the gate when transferring from American Airlines to Fijian. Then the plane stayed put for ages anyhow! The plane was delayed and my bag sent to San Francisco instead of Fiji

Everything you need to know for your flight from St. Louis to Buenos Aires

Information on your arrival and departure airports