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Portugal

$414+ Cheap flights from St. Louis (STL) to Portugal

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 4/14. Fares are subject to change and may not be available on all flights or dates of travel.
STL — LIS
Apr 28 — May 51
Tue 4/28
Tue 5/5
1 adult, Economy
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Cheap flight deals from St. Louis to Portugal

Cheapest flights from St. Louis to Portugal
Explore the most affordable flight options available from St. Louis to Portugal. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 29, 2026.

This Iberia deal was found by Cheapflights users on 3/24. 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.
Sun 4/269:40 pm
STL
-
LIS
1 stop19h 25m
Multiple Airlines
Wed 5/66:35 am
LIS
-
STL
2 stops18h 58m
Multiple Airlines
Deal found 3/24$662
This American Airlines deal was found by Cheapflights users on 3/24. 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 4/268:03 pm
STL
-
LIS
2 stops15h 42m
American Airlines
Wed 5/66:35 am
LIS
-
STL
2 stops18h 58m
American Airlines
Deal found 3/24$666
This Air Canada deal was found by Cheapflights users on 3/24. 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.
Wed 11/44:15 pm
STL
-
LIS
2 stops16h 20m
Multiple Airlines
Tue 11/105:00 am
LIS
-
STL
2 stops40h 30m
Multiple Airlines
Deal found 3/24$676
This United Airlines deal was found by Cheapflights users on 3/24. 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.
Wed 11/43:50 pm
STL
-
LIS
1 stop17h 00m
United Airlines
Tue 11/1010:15 am
LIS
-
STL
1 stop12h 25m
United Airlines
Deal found 3/24$692
This United Airlines deal was found by Cheapflights users on 3/28. 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.
Mon 10/268:25 am
STL
-
LIS
1 stop20h 50m
United Airlines
Thu 11/55:00 am
LIS
-
STL
2 stops16h 30m
United Airlines
Deal found 3/28$713
This KLM deal was found by Cheapflights users on 3/27. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 11/44:13 pm
STL
-
LIS
1 stop10h 47m
KLM
Tue 11/105:00 am
LIS
-
STL
2 stops18h 06m
KLM
Deal found 3/27$716
This KLM deal was found by Cheapflights users on 3/27. 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 KLM is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/34:13 pm
STL
-
LIS
1 stop10h 47m
KLM
Mon 11/911:25 am
LIS
-
STL
2 stops18h 14m
KLM
Deal found 3/27$717
This oojo deal was found by Cheapflights users on 3/27. 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 oojo is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/281:00 pm
STL
-
LIS
1 stop15h 05m
British Airways
Thu 11/511:05 am
LIS
-
STL
1 stop15h 50m
British Airways
Deal found 3/27$722
This CheapOair deal was found by Cheapflights users on 3/25. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/265:21 pm
STL
-
LIS
2 stops23h 44m
British Airways
Sat 5/26:55 pm
LIS
-
STL
2 stops27h 46m
British Airways
Deal found 3/25$723
This United Airlines deal was found by Cheapflights users on 3/27. 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.
Mon 12/71:27 pm
STL
-
OPO
2 stops16h 13m
United Airlines
Fri 12/1112:30 pm
OPO
-
STL
2 stops26h 07m
United Airlines
Deal found 3/27$765
This United Airlines deal was found by Cheapflights users on 3/26. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/46:49 pm
STL
-
OPO
2 stops30h 11m
United Airlines
Wed 10/212:25 pm
OPO
-
STL
2 stops39h 02m
United Airlines
Deal found 3/26$837
This American Airlines deal was found by Cheapflights users on 3/29. 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 10/42:45 pm
STL
-
OPO
2 stops19h 15m
American Airlines
Wed 10/218:20 am
OPO
-
STL
2 stops15h 44m
American Airlines
Deal found 3/29$852

Find flight deals from St. Louis to Portugal

Keep the following information in mind while searching for St. Louis to Portugal flight deals. Data was last updated March 29, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$662
(Iberia)

One-way from

$414
(Justfly.com)

Popular in

December

Cheapest in

April

Average price

$789
Provider with most accurate pricing for Lambert-St Louis-Lisbon Humberto Delgado flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-Lisbon Humberto Delgado flights.
Search Deals
From Lambert-St Louis to Portugal
Search Deals
One-way flight from Lambert-St Louis to Portugal
Search Deals
Highest demand for flights based on searches. 22% potential increase in price ($309 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 16% potential price decrease ($149 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Portugal 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 March 29, 2026.
Use the filters below to find and compare flights from St. Louis to Portugal that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Thu 4/16

1:29 pm-9:05 am

1 stop13h 36m

Lisbon Humberto Delgado

Thu 4/23

6:35 am-6:04 pm

2 stops17h 29m

$775

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Thu 4/16

12:27 pm-11:25 pm

2 stops28h 58m

Lisbon Humberto Delgado

Thu 4/23

6:35 am-10:17 pm

2 stops21h 42m

$816

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Sun 4/19

8:15 pm-9:20 am

2 stops31h 05m

Lisbon Humberto Delgado

Sun 4/26

5:05 am-11:11 pm

2 stops24h 06m

$822

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Sat 4/18

5:35 pm-6:45 pm

2 stops19h 10m

Lisbon Humberto Delgado

Sat 4/25

5:35 am-8:44 pm

2 stops21h 09m

$907

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Mon 5/11

5:36 pm-2:55 pm

2 stops15h 19m

Lisbon Humberto Delgado

Fri 5/22

10:00 am-5:05 pm

1 stop13h 05m

$926

St. LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Thu 4/16

1:46 pm-3:25 pm

2 stops19h 39m

Porto

Thu 4/23

5:00 am-8:44 pm

2 stops21h 44m

$953

St. LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Thu 4/16

11:37 am-11:15 am

2 stops17h 38m

Porto

Thu 4/23

4:35 pm-1:25 pm

1 stop26h 50m

$966

St. LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 5/10

6:45 am-10:40 am

2 stops21h 55m

Porto

Sun 5/17

5:00 am-9:09 pm

2 stops22h 09m

$970

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Tue 9/8

7:01 am-9:20 am

2 stops20h 19m

Lisbon Humberto Delgado

Wed 10/7

11:25 am-6:41 pm

1 stop13h 16m

$1,016

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Sat 8/29

5:32 pm-11:00 am

2 stops35h 28m

Lisbon Humberto Delgado

Wed 9/9

11:25 am-6:41 pm

1 stop13h 16m

$1,017

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/29

Showing 1-10 of 40 resultsSorted by cheapest first
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Best time to book a flight from St. Louis to Portugal

Have a flexible travel schedule? Discover the best time to fly to Portugal 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.

Cheapflights Insights

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

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

Currently, February is the cheapest month in which you can book a flight from St. Louis to Portugal (average of $469). Flying from St. Louis to Portugal in July is currently the most expensive (average of $839). 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.

Reviews of airlines servicing Portugal

Get insights into the airlines that provide service to Portugal. 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 Portugal. Reviews last updated March 29, 2026.
Read through reviews of airlines operating flights from St. Louis to Portugal, such as Delta,United Airlines, andAmerican Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
7.9
Good
8,359 reviews

Comfort

7.9

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Delta
7.9
Good
8,359 reviews
Delta
7.9
Good
8,359 reviews

Comfort

7.9

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
United Airlines
7.4
Good
9,509 reviews
Delta
7.9
Good
8,359 reviews

Comfort

7.9

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
American Airlines
7.1
Good
11,520 reviews
Delta
7.9
Good
8,359 reviews

Comfort

7.9

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Air Canada
7.1
Good
10,856 reviews
Delta
7.9
Good
8,359 reviews

Comfort

7.9

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.
Lufthansa
6.8
Okay
7,872 reviews
Delta
7.9
Good
8,359 reviews

Comfort

7.9

Crew

8.5

Overall

7.9

Entertainment

7.8

Boarding

8.1

Food

7.2

Reviews

1 / 20
6.0
Good

Jim,Nov 2025

AVL - ATL

The exit row seats without a seat in front are great for leg room but don’t have a fold out entertainment console so you’re forced to use the screen several feet in front of you (there is, at least, a remote). Best to bring a tablet loaded with entertainment or a book.

Related info for your journey

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

  • What airport do you fly from for flights from St. Louis to Portugal?

    Lambert-St Louis (STL), located 12.7 mi from the city center, is the airport you fly out of when you book flights from St. Louis to Portugal.

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

    Finnair, United Airlines, and KLM can get you from St. Louis to Portugal in just under 15h 26m. Your travel time can differ by up to 15h 39m. The distance from St. Louis to Portugal is about 4154 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines to fly from St. Louis to Portugal one-way?

    For one-way options, check prices for Lufthansa. According to our data, you can fly for as low as $342. Users have also found prices from $384 and $391 on Air Canada and United Airlines, respectively.

  • What are the most popular routes from St. Louis to Portugal?

    When deciding which route to take from St. Louis to Portugal consider Lambert-St Louis - Lisbon Humberto Delgado, Lambert-St Louis - Porto or Lambert-St Louis - Lajes as they are the most popular.

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

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

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

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

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

    Yes. Cheapflights offers flight deals from St. Louis to Portugal 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 St. Louis to Portugal?

    Currently, February is the cheapest month in which you can book a flight from St. Louis to Portugal (average of $469). Flying from St. Louis to Portugal in July is currently the most expensive (average of $839). 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

Browse thousands of different options on Cheapflights for your next trip

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Top 7 airlines flying from St. Louis to Portugal

Discover the top 7 airlines that operate flights from St. Louis to Portugal. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated March 29, 2026.
AirlineCheapestAverageFlexibilityOn-time
American AirlinesCheapest$505Average$1,180FlexibilityNo cancel feeOn-time71%
LufthansaCheapest$520Average$1,014FlexibilityNo cancel feeOn-time76%
DeltaCheapest$558Average$653FlexibilityNo cancel feeOn-timeN/A
IberiaCheapest$571Average$754FlexibilityNo cancel feeOn-time77%
British AirwaysCheapest$574Average$733FlexibilityNo cancel feeOn-time70%
United AirlinesCheapest$610Average$1,056FlexibilityNo cancel feeOn-time69%
Air CanadaCheapest$675Average$1,042FlexibilityNo cancel feeOn-time67%

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