HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Portugal

$239+ 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 1/18. Fares are subject to change and may not be available on all flights or dates of travel.
STL — LIS
Dec 13 — Dec 201
Sat 12/13
Sat 12/20
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from St. Louis to Portugal with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheap 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 November 13, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$479
(United Airlines)

One-way from

$239
(Kiwi.com)

Popular in

June

Cheapest in

February

Average price

$761
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. 17% potential increase in price ($204 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($33 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in November 2025
Search Deals

Find 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 November 13, 2025.

This Expedia deal was found by Cheapflights users on 11/11. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/86:42 pmSTL - LIS
2 stops22h 48mLufthansa
Wed 12/245:00 amLIS - STL
1 stop14h 55mLufthansa
Deal found 11/11$488
This Delta deal was found by Cheapflights users on 11/13. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/317:10 amSTL - LIS
1 stop19h 30mDelta
Tue 1/135:00 amLIS - STL
2 stops21h 45mDelta
Deal found 11/13$496
This Delta deal was found by Cheapflights users on 11/11. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/317:00 amSTL - LIS
2 stops19h 00mDelta
Thu 1/155:00 amLIS - STL
2 stops21h 39mDelta
Deal found 11/11$500
This Air Canada deal was found by Cheapflights users on 11/11. 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.
Mon 12/84:05 pmSTL - LIS
1 stop11h 15mAir Canada
Wed 12/2411:00 amLIS - STL
1 stop34h 29mAir Canada
Deal found 11/11$504
This Finnair deal was found by Cheapflights users on 11/12. 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 Finnair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 12/1210:56 amSTL - LIS
1 stop15h 54mMultiple Airlines
Tue 12/1611:05 amLIS - STL
1 stop15h 33mMultiple Airlines
Deal found 11/12$506
This Air Canada deal was found by Cheapflights users on 11/11. 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 12/314:05 pmSTL - LIS
1 stop10h 50mAir Canada
Sat 1/1711:20 amLIS - STL
2 stops31h 09mAir Canada
Deal found 11/11$507
This Air Canada deal was found by Cheapflights users on 11/11. 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 12/314:05 pmSTL - LIS
1 stop10h 50mAir Canada
Fri 1/1611:20 amLIS - STL
1 stop34h 09mAir Canada
Deal found 11/11$508
This United Airlines deal was found by Cheapflights users on 11/11. 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.
Tue 11/188:25 amSTL - LIS
1 stop19h 50mUnited Airlines
Wed 2/411:20 amLIS - STL
2 stops35h 58mUnited Airlines
Deal found 11/11$538
This Cheapflightsfares deal was found by Cheapflights users on 11/11. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/186:43 pmSTL - LIS
2 stops22h 47mLufthansa
Wed 2/46:10 amLIS - STL
2 stops23h 49mLufthansa
Deal found 11/11$541
This United Airlines deal was found by Cheapflights users on 11/11. 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.
Thu 11/277:00 amSTL - OPO
1 stop20h 30mUnited Airlines
Wed 12/106:00 amOPO - STL
1 stop13h 55mUnited Airlines
Deal found 11/11$669
This KLM deal was found by Cheapflights users on 11/12. 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.
Fri 12/122:38 pmSTL - OPO
2 stops13h 52mKLM
Tue 12/169:55 amOPO - STL
2 stops16h 52mKLM
Deal found 11/12$876
This Mytrip deal was found by Cheapflights users on 11/12. 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.
Fri 12/124:05 pmSTL - OPO
3 stops34h 05mMultiple Airlines
Tue 12/1612:40 pmOPO - STL
3 stops29h 35mMultiple Airlines
Deal found 11/12$1,226

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 November 13, 2025.
Use the filters below to find and compare flights from St. Louis to Portugal that are best for you.

Fly from

St. Louis

Fly to

Portugal

Route

Depart

Return

Price

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Thu 1/8

7:00 am-9:20 am

2 stops20h 20m

Lisbon Humberto Delgado

Wed 1/21

5:00 am-1:55 pm

1 stop14h 55m

$479

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Tue 3/10

10:00 am-10:15 am

2 stops19h 15m

Lisbon Humberto Delgado

Wed 3/18

5:00 am-2:55 pm

1 stop14h 55m

$487

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Sat 3/7

8:00 am-8:55 am

2 stops18h 55m

Lisbon Humberto Delgado

Thu 3/19

5:00 am-12:21 pm

2 stops36h 21m

$493

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Sun 2/15

4:05 pm-9:20 am

1 stop11h 15m

Lisbon Humberto Delgado

Sun 2/22

5:00 am-10:00 pm

2 stops23h 00m

$494

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Tue 2/17

9:45 am-8:00 am

1 stop16h 15m

Lisbon Humberto Delgado

Wed 2/25

5:00 am-8:11 pm

2 stops21h 11m

$496

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Thu 2/19

6:30 am-8:55 am

1 stop20h 25m

Lisbon Humberto Delgado

Thu 2/26

5:00 am-8:11 pm

2 stops21h 11m

$496

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Mon 3/9

11:25 am-8:10 am

2 stops15h 45m

Lisbon Humberto Delgado

Thu 3/19

5:00 am-9:00 pm

2 stops21h 00m

$496

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Wed 12/31

7:10 am-8:40 am

1 stop19h 30m

Lisbon Humberto Delgado

Mon 1/19

10:00 am-8:06 pm

1 stop16h 06m

$499

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Fri 1/2

6:00 am-8:00 am

2 stops20h 00m

Lisbon Humberto Delgado

Thu 1/15

10:00 am-8:06 pm

1 stop16h 06m

$499

St. LouisLisbon

STL - LIS

STLLIS

Lambert-St Louis

Fri 1/2

6:00 am-8:00 am

2 stops20h 00m

Lisbon Humberto Delgado

Wed 1/14

11:25 am-8:53 am

2 stops27h 28m

$500

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/11

Showing 1-10 of 28 results
1
2
3

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 $512). Flying from St. Louis to Portugal in July is currently the most expensive (average of $897). 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.

What is the cheapest time of day to fly from STL to PT?

Find hourly flight availability from St. Louis to Portugal. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 13, 2025.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 33% on flights from St. Louis to Portugal by exploring options for tickets at noon.

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 November 13, 2025.
Read through reviews of airlines operating flights from St. Louis to Portugal, such as United Airlines, American Airlines, and Air Canada. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
United Airlines
7.4
Good
9,017 reviews

Overall

7.4

Boarding

7.7

Entertainment

7.1

Food

6.6

Comfort

7.3

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
United Airlines
7.4
Good
9,017 reviews
United Airlines
7.4
Good
9,017 reviews

Overall

7.4

Boarding

7.7

Entertainment

7.1

Food

6.6

Comfort

7.3

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
American Airlines
7.2
Good
11,051 reviews
United Airlines
7.4
Good
9,017 reviews

Overall

7.4

Boarding

7.7

Entertainment

7.1

Food

6.6

Comfort

7.3

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Air Canada
7.1
Good
10,448 reviews
United Airlines
7.4
Good
9,017 reviews

Overall

7.4

Boarding

7.7

Entertainment

7.1

Food

6.6

Comfort

7.3

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Iberia
7.0
Good
3,012 reviews
United Airlines
7.4
Good
9,017 reviews

Overall

7.4

Boarding

7.7

Entertainment

7.1

Food

6.6

Comfort

7.3

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000
Lufthansa
6.8
Okay
7,572 reviews
United Airlines
7.4
Good
9,017 reviews

Overall

7.4

Boarding

7.7

Entertainment

7.1

Food

6.6

Comfort

7.3

Crew

8.1

Reviews

1 / 20
2.0
Mediocre

Sebrena,Oct 2025

IAH - RSW

The worst that I have ever experienced in my life so bad if it was free I'm not ever going to use your Airline again I dont believe ..... very disappointed 😞 😔0000000000000

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?

    United Airlines can get you from St. Louis to Portugal in just under 20h 20m. Your travel time can differ by up to . The distance from St. Louis to Portugal is about 4212 mi.

  • 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 $512). Flying from St. Louis to Portugal in July is currently the most expensive (average of $897). 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

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for St. Louis to Portugal

See prices for flight routes from nearby airports that may be better suited for you.
St. Louis to Heathrow flights
Kansas City to Leonardo da Vinci/Fiumicino flights
Kansas City to Dublin flights
Kansas City to Heathrow flights
Kansas City to Frankfurt flights
St. Louis to Frankfurt flights
St. Louis to Dublin flights
St. Louis to Gatwick flights
Kansas City to Charles de Gaulle flights
St. Louis to Charles de Gaulle flights
St. Louis to Leonardo da Vinci/Fiumicino flights
Kansas City to Madrid flights
Kansas City to Gatwick flights
St. Louis to Athens flights
St. Louis to Edinburgh flights
St. Louis to Zurich flights
St. Louis to Orly flights
St. Louis to London City flights
St. Louis to Istanbul flights
St. Louis to Barcelona-El Prat flights
Kansas City to Vicenza flights
Kansas City to Barcelona-El Prat flights
St. Louis to Lisbon flights
St. Louis to Bruxelles-National flights
St. Louis to Sarajevo flights
St. Louis to Madrid flights
St. Louis to Amsterdam flights
St. Louis to Sabiha Gokcen flights
Kansas City to Amsterdam flights
St. Louis to Vicenza flights
Kansas City to Orly flights
Kansas City to Keflavik Intl flights
Kansas City to London City flights
Kansas City to Prague flights
Kansas City to Malpensa flights
Kansas City to Frederic Chopin flights
Kansas City to Lisbon flights
St. Louis to Stansted flights
Kansas City to Edinburgh flights
Kansas City to Linate flights
Springfield to Heathrow flights
Springfield to Frankfurt flights
Kansas City to Athens flights
Kansas City to Istanbul flights
Springfield to Istanbul flights
St. Louis to Cork flights
St. Louis to Oslo Gardermoen flights
Kansas City to Oslo Gardermoen flights
Kansas City to Copenhagen flights
St. Louis to Keflavik Intl flights

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 November 13, 2025.
AirlineCheapestAverageFlexibilityOn-time
LufthansaCheapest$549Average$1,077FlexibilityNo cancel feeOn-time76%
IberiaCheapest$593Average$761FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$605Average$1,075FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$660Average$1,167FlexibilityNo cancel feeOn-time71%
British AirwaysCheapest$667Average$847FlexibilityNo cancel feeOn-time70%
DeltaCheapest$680Average$884FlexibilityNo cancel feeOn-timeN/A
Air CanadaCheapest$823Average$1,106FlexibilityNo cancel feeOn-time67%

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.