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St. Louis

$523+ 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 4/22. Fares are subject to change and may not be available on all flights or dates of travel.
OPO — STL
Dec 26 — Jan 21
Fri 12/26
Fri 1/2
1 adult, Economy
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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 November 26, 2025.

This American Airlines deal was found by Cheapflights users on 11/26. 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.
Fri 12/512:25 pmOPO - STL
2 stops31h 59mAmerican Airlines
Sat 12/137:35 pmSTL - OPO
2 stops38h 25mAmerican Airlines
Deal found 11/26$730
This American Airlines deal was found by Cheapflights users on 11/26. 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.
Wed 12/38:40 pmOPO - STL
2 stops19h 57mAmerican Airlines
Sat 12/137:35 pmSTL - OPO
2 stops34h 10mAmerican Airlines
Deal found 11/26$736
This American Airlines deal was found by Cheapflights users on 11/26. 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.
Wed 12/38:40 pmOPO - STL
2 stops18h 10mAmerican Airlines
Fri 12/124:36 pmSTL - OPO
2 stops37h 09mAmerican Airlines
Deal found 11/26$743
This American Airlines deal was found by Cheapflights users on 11/26. 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.
Fri 12/512:25 pmOPO - STL
2 stops31h 59mAmerican Airlines
Tue 12/164:36 pmSTL - OPO
2 stops33h 04mAmerican Airlines
Deal found 11/26$762
This American Airlines deal was found by Cheapflights users on 11/26. 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.
Wed 12/38:40 pmOPO - STL
2 stops18h 10mAmerican Airlines
Tue 12/164:36 pmSTL - OPO
2 stops33h 04mAmerican Airlines
Deal found 11/26$770
This Iberia deal was found by Cheapflights users on 11/26. 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 Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/88:40 pmOPO - STL
2 stops32h 07mIberia
Sun 12/142:54 pmSTL - OPO
2 stops38h 51mIberia
Deal found 11/26$771
This Iberia deal was found by Cheapflights users on 11/26. 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 Iberia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/412:25 pmOPO - STL
2 stops38h 13mIberia
Sun 12/142:54 pmSTL - OPO
2 stops38h 51mIberia
Deal found 11/26$774
This British Airways deal was found by Cheapflights users on 11/26. 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.
Wed 12/36:35 pmOPO - STL
2 stops51h 59mBritish Airways
Fri 12/1211:50 amSTL - OPO
2 stops25h 10mBritish Airways
Deal found 11/26$778
This British Airways deal was found by Cheapflights users on 11/26. 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.
Sat 12/67:50 pmOPO - STL
2 stops31h 38mBritish Airways
Sat 12/132:09 pmSTL - OPO
2 stops23h 06mBritish Airways
Deal found 11/26$781

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 November 26, 2025.

Round-trip from

$729
(American Airlines)

One-way from

$523
(British Airways)
From Porto to Lambert-St Louis
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One-way flight from Porto to Lambert-St Louis
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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 November 26, 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

Wed 1/14

12:30 pm-4:03 pm

2 stops57h 33m

Lambert-St Louis

Sun 1/18

3:50 pm-11:40 am

1 stop13h 50m

$838

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sat 12/6

6:00 am-5:29 pm

2 stops17h 29m

Lambert-St Louis

Mon 12/15

2:38 pm-10:30 am

2 stops13h 52m

$840

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Wed 1/14

11:15 am-8:43 pm

2 stops39h 28m

Lambert-St Louis

Sun 1/18

6:35 am-10:30 am

2 stops21h 55m

$845

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sun 12/7

8:20 am-2:49 pm

2 stops36h 29m

Lambert-St Louis

Sat 12/13

7:35 pm-4:00 pm

2 stops38h 25m

$855

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Mon 12/8

8:20 am-11:14 am

2 stops32h 54m

Lambert-St Louis

Sat 12/13

4:49 pm-11:45 am

2 stops36h 56m

$879

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Wed 4/22

8:20 am-11:24 pm

2 stops21h 04m

$523

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Sat 4/25

12:25 pm-7:30 pm

2 stops37h 05m

$545

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Fri 4/24

12:25 pm-11:24 pm

2 stops16h 59m

$550

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Thu 4/23

8:20 am-11:24 pm

2 stops21h 04m

$550

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Mon 4/20

8:20 am-9:48 pm

2 stops19h 28m

$550

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/24

Showing 1-10 of 17 results
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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.

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.

  • How long is the flight from Porto to St. Louis?

    Airlines like Lufthansa and KLM fly from Porto to St. Louis in about 17h 29m. The time it takes to get you to your destination can typically vary by up to 40h 04m. There are 4154 mi between Porto and St. Louis. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • 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.

See more FAQs

Traveling to a place near St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Edwardsville
O'Fallon
Fairview Heights
Maryland Heights
Collinsville
Swansea
Eureka
Glencoe
St. Peters
Chesterfield
Alton
Farmington
Festus

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