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Porto Alegre

$1,123+ Cheap flights from St. Louis (STL) to Porto Alegre (POA)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 1/5. Fares are subject to change and may not be available on all flights or dates of travel.
STL — POA
Aug 19 — Aug 261
Tue 8/19
Tue 8/26
1 adult, Economy
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Cheap flight deals from St. Louis to Porto Alegre

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Porto Alegre (POA). 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 14, 2025.

Round-trip from

$1,123
(Expedia)
From Lambert-St Louis to Porto Alegre Salgado Filho
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Find flight deals from St. Louis to Porto Alegre

Cheapest flights from St. Louis to Porto Alegre
Explore the most affordable flight options available from St. Louis to Porto Alegre. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 14, 2025.

This United Airlines deal was found by Cheapflights users on 8/14. 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.
Sat 9/273:23 pmSTL - POA
2 stops21h 07mUnited Airlines
Sat 10/1111:30 amPOA - STL
2 stops28h 57mUnited Airlines
Deal found 8/14$1,262
This American Airlines deal was found by Cheapflights users on 8/14. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/279:57 amSTL - POA
3 stops22h 28mAmerican Airlines
Sat 10/115:15 pmPOA - STL
2 stops26h 13mAmerican Airlines
Deal found 8/14$2,810

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Porto Alegre 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 14, 2025.
Use the filters below to find and compare flights from St. Louis to Porto Alegre that are best for you.

Fly from

St. Louis

Fly to

Porto Alegre

Route

Depart

Return

Price

St. LouisPorto Alegre

STL - POA

STLPOA

Lambert-St Louis

Mon 1/5

10:00 am-6:45 pm

2 stops29h 45m

Porto Alegre Salgado Filho

Sat 1/17

7:45 am-11:40 pm

2 stops18h 55m

$1,123

St. LouisPorto Alegre

STL - POA

STLPOA

Lambert-St Louis

Sat 9/27

3:23 pm-2:30 pm

2 stops21h 07m

Porto Alegre Salgado Filho

Sat 10/11

11:30 am-2:27 pm

2 stops28h 57m

$1,262

St. LouisPorto Alegre

STL - POA

STLPOA

Lambert-St Louis

Mon 1/5

10:00 am-6:45 pm

2 stops29h 45m

Porto Alegre Salgado Filho

Fri 1/16

4:30 am-11:44 am

2 stops34h 14m

$1,472

St. LouisPorto Alegre

STL - POA

STLPOA

Lambert-St Louis

Mon 1/5

4:05 pm-4:30 pm

2 stops21h 25m

Porto Alegre Salgado Filho

Sat 1/17

5:55 pm-12:20 pm

3 stops21h 25m

$2,057

St. LouisPorto Alegre

STL - POA

STLPOA

Lambert-St Louis

Sat 9/27

9:57 am-10:25 am

3 stops22h 28m

Porto Alegre Salgado Filho

Sat 10/11

5:15 pm-5:28 pm

2 stops26h 13m

$2,810

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/12

Best time to book a flight from St. Louis to Porto Alegre

Have a flexible travel schedule? Discover the best time to fly to Porto Alegre from St. Louis with our price prediction graph.
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.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Porto Alegre. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • Can I find deals for flights from St. Louis to Porto Alegre that include hotel bookings?

    Yes. In addition to deals on St. Louis to Porto Alegre flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Porto Alegre?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Porto Alegre.

  • Can I find deals for business class flights from St. Louis to Porto Alegre?

    Yes. Cheapflights offers flight deals from St. Louis to Porto Alegre by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

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