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St. Louis

$976+ Cheap flights from Porto (OPO) to St. Louis (STL)

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 5/31. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — STL
abr. 22 — abr. 291
mar. 4/22
mar. 4/29
1 adult, Economy
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Cheap flight deals from Porto to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from Porto (OPO) to St. Louis (STL). 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 abril 17, 2025.

Round-trip from

$976
(United Airlines)
From Porto to Lambert-St Louis
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Find flight deals from Porto to St. Louis

Cheapest flights from Porto to St. Louis
Explore the most affordable flight options available from Porto to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on abril 17, 2025.

This United Airlines deal was found by Cheapflights users on 4/16. 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.
sáb. 5/316:00 amOPO - STL
2 stops19h 37mUnited Airlines
sáb. 6/71:30 pmSTL - OPO
1 stop14h 05mUnited Airlines
Deal found 4/16$976
This Mytrip deal was found by Cheapflights users on 4/16. 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 Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 5/316:15 amOPO - STL
3 stops34h 30mMultiple Airlines
sáb. 6/77:30 amSTL - OPO
2 stops20h 05mMultiple Airlines
Deal found 4/16$1,082

Cheapflights Fare Finder

Customize your flight search to find flights from Porto to St. Louis 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 abril 17, 2025.
Use the filters below to find and compare flights from Porto to St. Louis that are best for you.

Fly from

Porto

Fly to

St. Louis

Route

Depart

Return

Price

PortoSt. Louis

OPO - STL

OPOSTL

Porto

sáb. 5/31

6:00 am-7:37 pm

2 stops19h 37m

Lambert-St Louis

sáb. 6/7

1:30 pm-9:35 am

1 stop14h 05m

$976

PortoSt. Louis

OPO - STL

OPOSTL

Porto

sáb. 5/31

6:15 am-10:45 am

3 stops34h 30m

Lambert-St Louis

sáb. 6/7

7:30 am-9:35 am

2 stops20h 05m

$1,082

Flights are sorted by cheapest round-trip flights first.

Deals found on 4/16

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

Have a flexible travel schedule? Discover the best time to fly to St. Louis from Porto 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.

Cheapflights Insights

Everything you need to know about your flight from Porto to St. Louis

Rainfall in St. Louis by month

Plan your trip to St. Louis by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in St. Louis ranges from 2.2 - 4.7 inches per month. May is typically the wettest month, when rainfall can reach 4.7 in. February is typically the driest time to visit St. Louis when rainfall is around 2.2 in.

Temperature in St. Louis by month

Plan your trip to St. Louis by taking into account the average temperature totals by month.

If weather is an important factor for your trip to St. Louis, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 80.6 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 32.0 F).

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to St. Louis. Reviews last updated abril 17, 2025.
United Airlines
7.4
Good
8,667 reviews

Boarding

7.7

Comfort

7.3

Crew

8.1

Entertainment

7.0

Food

6.6

Overall

7.4

Reviews

1 / 20
4.0
Okay

Thomas,Apr 2025

TPE - SFO

The boarding experience was okay. The dietary food choices were limited, the midway snacks were hard and dry. The seat was uncomfortable - stiff seat cushion, seat back kept springing back to the upright position, narrow seat width. Love the app and the ability to track my luggage. Flight crew was efficient.
United Airlines
7.4
Good
8,667 reviews
United Airlines
7.4
Good
8,667 reviews

Boarding

7.7

Comfort

7.3

Crew

8.1

Entertainment

7.0

Food

6.6

Overall

7.4

Reviews

1 / 20
4.0
Okay

Thomas,Apr 2025

TPE - SFO

The boarding experience was okay. The dietary food choices were limited, the midway snacks were hard and dry. The seat was uncomfortable - stiff seat cushion, seat back kept springing back to the upright position, narrow seat width. Love the app and the ability to track my luggage. Flight crew was efficient.

Related info for your journey

Find useful and relevant information for your journey from Porto to St. Louis. 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 Porto to St. Louis that include hotel bookings?

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

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

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

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

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

  • What is the cheapest month to book a flight from Porto to St. Louis?

    Currently, August is the cheapest month in which you can book a flight from Porto to St. Louis (average of $311). Flying from Porto to St. Louis in March is currently the most expensive (average of $356). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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