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St. Louis

$394+ Cheap flights from Porto (OPO) to St. Louis (STL)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 4/6. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — STL
Feb 25 — Mar 41
Tue 2/25
Tue 3/4
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 February 20, 2025.

Round-trip from

$762
(Lufthansa)

One-way from

$394
(Kiwi.com)
From Porto to Lambert-St Louis
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One-way flight 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 February 20, 2025.

This Lufthansa deal was found by Cheapflights users on 2/20. 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 Lufthansa is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/88:40 amOPO - STL
2 stops17h 10mMultiple Airlines
Wed 3/121:05 pmSTL - OPO
2 stops17h 35mMultiple Airlines
Deal found 2/20$762
This Gotogate deal was found by Cheapflights users on 2/20. 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 Gotogate is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 3/86:05 amOPO - STL
2 stops21h 44mLufthansa
Wed 3/121:05 pmSTL - OPO
2 stops21h 10mLufthansa
Deal found 2/20$763
This United Airlines deal was found by Cheapflights users on 2/19. 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.
Sun 4/66:00 amOPO - STL
2 stops36h 20mUnited Airlines
Sun 4/133:30 pmSTL - OPO
1 stop13h 45mUnited Airlines
Deal found 2/19$809
This American Airlines deal was found by Cheapflights users on 2/20. 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.
Sun 4/68:15 amOPO - STL
2 stops21h 18mAmerican Airlines
Wed 4/97:19 amSTL - OPO
2 stops18h 16mAmerican Airlines
Deal found 2/20$912
This British Airways deal was found by Cheapflights users on 2/20. 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 British Airways is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/69:20 pmOPO - STL
2 stops24h 51mBritish Airways
Thu 4/103:29 pmSTL - OPO
2 stops22h 56mBritish Airways
Deal found 2/20$995
This Air Canada deal was found by Cheapflights users on 2/20. 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 Air Canada is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/610:00 amOPO - STL
3 stops17h 48mAir Canada
Wed 4/93:30 pmSTL - OPO
2 stops19h 55mAir Canada
Deal found 2/20$1,655

Find flights from Porto to St. Louis within your budget

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 February 20, 2025.

Fly from

Porto

Fly to

St. Louis

Route

Depart

Return

Price

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sat 3/8

8:40 am-7:50 pm

2 stops17h 10m

Lambert-St Louis

Wed 3/12

1:05 pm-11:40 am

2 stops17h 35m

$762

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sat 3/8

6:05 am-9:49 pm

2 stops21h 44m

Lambert-St Louis

Wed 3/12

1:05 pm-3:15 pm

2 stops21h 10m

$763

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sun 4/6

6:00 am-12:20 pm

2 stops36h 20m

Lambert-St Louis

Sun 4/13

3:30 pm-11:15 am

1 stop13h 45m

$809

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sun 4/6

8:15 am-11:33 pm

2 stops21h 18m

Lambert-St Louis

Wed 4/9

7:19 am-7:35 am

2 stops18h 16m

$912

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sun 4/6

9:20 pm-4:11 pm

2 stops24h 51m

Lambert-St Louis

Thu 4/10

3:29 pm-8:25 pm

2 stops22h 56m

$995

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sun 4/6

10:00 am-9:48 pm

3 stops17h 48m

Lambert-St Louis

Wed 4/9

3:30 pm-5:25 pm

2 stops19h 55m

$1,655

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sun 4/6

10:55 am-11:46 pm

3 stops42h 51m

$394

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sat 5/17

4:35 pm-1:30 pm

1 stop26h 55m

$906

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/20

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.

Travel insights for flights from Porto to St. Louis

Get recent, data-driven insights about flights from Porto to St. Louis including ideal travel times, pricing trends, and more.

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 February 20, 2025.
United Airlines
7.4
Good
8,766 reviews

Crew

8.1

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.7

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

United Airlines
7.4
Good
8,766 reviews
United Airlines
7.4
Good
8,766 reviews

Crew

8.1

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.7

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

American Airlines
7.2
Good
10,000 reviews
United Airlines
7.4
Good
8,766 reviews

Crew

8.1

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.7

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

Air Canada
7.0
Good
8,748 reviews
United Airlines
7.4
Good
8,766 reviews

Crew

8.1

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.7

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

Lufthansa
6.7
Okay
6,984 reviews
United Airlines
7.4
Good
8,766 reviews

Crew

8.1

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.7

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

British Airways
6.6
Okay
6,763 reviews
United Airlines
7.4
Good
8,766 reviews

Crew

8.1

Overall

7.4

Boarding

7.7

Comfort

7.3

Entertainment

7.1

Food

6.7

Reviews

1 / 20

4.0
Okay

Patti,Feb 2025

FCO - EWR

The food was inedible! We are in the food business and aren’t sure who got this contract. But prisoners eat better. The food was so bad. I ate just a small amount and it made me nauseous. Everything is over microwaved too. And what is with the options? Vegan and vegetarian, but no keto or carnivore? I get that may be more expensive. But I’d gladly pay if it even was an option. But it’s not. There are many fresh options that could have been offered that don’t have to be heated too!

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

Traveling to a place near Porto?

Book flights to Porto if you plan to visit one of these locations
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Fairview Heights
Maryland Heights
Collinsville
Wentzville
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Alton
Farmington
Chesterfield

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