Cheap flights from St. Louis to Buenos Aires from $926
This is the cheapest round-trip flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Buenos Aires departing on 9/3. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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United Airlines flights from St. Louis to Buenos Aires
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How to get the cheapest flight ticket from St. Louis to Buenos Aires
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Buenos Aires?
The cheapest month to fly to Buenos Aires from St. Louis is in August. Flight prices, which tend to average around $1,039, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of August, then book flights to Buenos Aires from St. Louis during September instead. Flights to Buenos Aires in September, while not as cheap as those in August, still average around $1,123.
What is the cheapest day to depart on your flight to Buenos Aires?
On average, the least expensive day to fly to Buenos Aires from St. Louis is on a Tuesday. momondo users have found tickets for Tuesday departures for as low as $1,163. However, this price may fluctuate depending on the airline, the season, and holidays. Be sure to avoid booking your departure on a Friday as prices are generally higher than usual. According to our data, the average ticket price to Buenos Aires on Friday is $1,386.
When to book flights from St. Louis to Buenos Aires
Cheap St. Louis to Buenos Aires (STL to BUE) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Buenos Aires
How far is Lambert-St Louis to Buenos Aires by plane?
The straight-line distance from Lambert-St Louis to Buenos Aires is 5450.9 mi. Typically, this will take 12h 40m by plane in normal conditions.
When did momondo last update prices for flights from Lambert-St Louis Airport to Buenos Aires?
Prices for flights from Lambert-St Louis Airport to Buenos Aires are refreshed on a daily basis.
How many operators does momondo search for flights from Lambert-St Louis Airport to Buenos Aires?
As of May 2025, there are 3 operators available to choose from for flights from Lambert-St Louis Airport to Buenos Aires.
How old do you have to be to fly from Lambert-St Louis Airport to Buenos Aires?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Lambert-St Louis Airport to Buenos Aires.
What documentation or ID do you need to fly to Buenos Aires?
The travel and health documents required for your trip to Buenos Aires can vary based on your itinerary and personal situation. As a rule, consider having multiple documents such as a national ID card or driver’s license, and a passport valid for six-months after you plan to arrive at Buenos Aires. We always recommend checking with your airline or a trusted third party such as IATA to get advice.
What is the most popular airline from St. Louis to Buenos Aires?
Based on momondo bookings for this flight route, the most popular airline on flight routes from St. Louis to Buenos Aires is Delta (55% of total bookings). The next most popular airlines are United Airlines (22%), LATAM Airlines (13%), and American Airlines (10%).
Best airlines flying from St. Louis to Buenos Aires
Compare and see reviews for airlines that fly from St. Louis to Buenos Aires with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $1,023 | Free Cancellation | Rating 8.0 7,934 reviews | |||
| PriceFrom $1,025 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $1,053 | Free Cancellation | Rating 7.4 8,696 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from St. Louis to Buenos Aires?
To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Buenos Aires from St. Louis.
Can I find flights from St. Louis to Buenos Aires with flexible booking policies on momondo?
Yes. All flights to Buenos Aires from St. Louis on momondo can be compared and filtered by various policies on offer, including flexible booking.
How can momondo help me find flights from St. Louis to Buenos Aires?
Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Buenos Aires from St. Louis.
I’m not ready to book a flight from St. Louis to Buenos Aires right now. Can momondo alert me if prices change?
Yes momondo offers price alerts on flights to Buenos Aires from St. Louis. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.