What is the cheapest airline that flies from Lambert-St Louis to Portugal?

United Airlines, British Airways, and Lufthansa are the most popular carriers operating from Lambert-St Louis to Portugal

What airlines fly to Portugal?

United Airlines, Air Canada and Lufthansa are the top three most popular airlines that fly to Portugal from St. Louis according to our data. United Airlines is the first choice among our users, with 53% of people opting to fly with this airline when traveling to Portugal. Keep in mind that there are 6 different airlines that fly to Portugal on a routine basis, so you have a few additional options to choose from.

When did momondo last update prices for flights from Lambert-St Louis Airport to Portugal?

Prices for flights from Lambert-St Louis Airport to Portugal are refreshed on a daily basis.

How many operators does momondo search for flights from Lambert-St Louis Airport to Portugal?

The number of operators available for flights from Lambert-St Louis Airport to Portugal is 6 as of November 2026.

How old do you have to be to fly from Lambert-St Louis Airport to Portugal?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to Portugal.

What documentation or ID do you need to fly to Portugal?

The travel and health documents you'll need for your trip to Portugal may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Portugal. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$354 Cheap Flights from St. Louis to Portugal in 2026/27

Discover deals from 900+ travel sites with momondo.

Find the cheapest flights from St. Louis to Portugal

Round-trip

One-way

Last minute

Cheap round-trip flights

Enter your travel dates to find the best prices.

4:39 pm - 9:30 amSTL Lambert-St Louis-OPO Porto

10h 51m1 stop Newark

6:00 am - 1:45 pmOPO Porto-STL Lambert-St Louis

13h 45m1 stop Frankfurt am Main

$718United Airlines

Tue, Feb 23 - Fri, Feb 26

4:39 pm - 9:30 amSTL Lambert-St Louis-OPO Porto

10h 51m1 stop Newark

6:00 am - 1:45 pmOPO Porto-STL Lambert-St Louis

13h 45m1 stop Frankfurt am Main

$719United Airlines

Tue, Feb 23 - Fri, Feb 26

4:05 pm - 9:20 amSTL Lambert-St Louis-LIS Lisbon Humberto Delgado

11h 15m1 stop Toronto Pearson Intl

5:00 am - 1:45 pmLIS Lisbon Humberto Delgado-STL Lambert-St Louis

14h 45m1 stop Frankfurt am Main

$731Multiple Airlines

Mon, Dec 7 - Wed, Dec 23

10:06 am - 9:00 amSTL Lambert-St Louis-LIS Lisbon Humberto Delgado

16h 54m2 stops Atlanta Hartsfield-Jackson Boston Logan Intl

11:15 am - 8:43 pmLIS Lisbon Humberto Delgado-STL Lambert-St Louis

39h 28m2 stops Boston Logan Intl Detroit Metropolitan Wayne County

$736Virgin Atlantic

Mon, Dec 7 - Wed, Dec 23

9:20 am - 10:40 amSTL Lambert-St Louis-LIS Lisbon Humberto Delgado

19h 20m2 stops Chicago O'Hare Intl Montreal Pierre Elliott Trudeau Intl

10:55 am - 9:23 pmLIS Lisbon Humberto Delgado-STL Lambert-St Louis

40h 28m2 stops Montreal Pierre Elliott Trudeau Intl Chicago O'Hare Intl

$797Air Canada

Mon, Feb 22 - Fri, Feb 26

4:05 pm - 9:20 amSTL Lambert-St Louis-LIS Lisbon Humberto Delgado

11h 15m1 stop Toronto Pearson Intl

12:50 pm - 5:34 pmLIS Lisbon Humberto Delgado-STL Lambert-St Louis

34h 44m2 stops Montreal Pierre Elliott Trudeau Intl Chicago O'Hare Intl

$818Air Canada

Mon, Nov 30 - Tue, Mar 2

11:00 am - 1:30 pmSTL Lambert-St Louis-LIS Lisbon Humberto Delgado

20h 30m2 stops Newark Munich Franz Josef Strauss

5:00 am - 1:45 pmLIS Lisbon Humberto Delgado-STL Lambert-St Louis

14h 45m1 stop Frankfurt am Main

$818Lufthansa

Fri, Jan 29 - Wed, Feb 3

11:00 am - 1:30 pmSTL Lambert-St Louis-LIS Lisbon Humberto Delgado

20h 30m2 stops Newark Munich Franz Josef Strauss

5:00 am - 9:49 pmLIS Lisbon Humberto Delgado-STL Lambert-St Louis

22h 49m2 stops Frankfurt am Main Newark

$823Lufthansa

Fri, Jan 29 - Wed, Feb 3

7:00 am - 8:00 amSTL Lambert-St Louis-LIS Lisbon Humberto Delgado

19h 00m1 stop New York LaGuardia

10:00 am - 9:21 pmLIS Lisbon Humberto Delgado-STL Lambert-St Louis

17h 21m1 stop New York John F Kennedy Intl

$835Delta

Sun, Nov 29 - Thu, Mar 4

7:00 am - 8:00 amSTL Lambert-St Louis-LIS Lisbon Humberto Delgado

19h 00m1 stop New York LaGuardia

10:00 am - 9:21 pmLIS Lisbon Humberto Delgado-STL Lambert-St Louis

17h 21m1 stop New York John F Kennedy Intl

$835Delta

Sun, Nov 29 - Tue, Mar 2

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Air Canada flights from St. Louis to Portugal

Our best Air Canada deals on St. Louis to Portugal flight tickets

Air Canada

Feb 22

STL9:20 amLambert-St Louis

19h 20m

2 stops

LIS10:40 amLisbon Humberto Delgado

Feb 26

LIS10:55 amLisbon Humberto Delgado

40h 28m

2 stops

STL9:23 pmLambert-St Louis

$797

Air Canada

Nov 29

STL6:50 pmLambert-St Louis

33h 50m

2 stops

LIS10:40 amLisbon Humberto Delgado

Mar 4

LIS8:55 amLisbon Humberto Delgado

35h 22m

2 stops

STL2:17 pmLambert-St Louis

$818

Air Canada

Dec 1

STL4:05 pmLambert-St Louis

32h 50m

2 stops

LIS6:55 amLisbon Humberto Delgado

Mar 4

LIS8:55 amLisbon Humberto Delgado

35h 22m

2 stops

STL2:17 pmLambert-St Louis

$822

United Airlines flights from St. Louis to Portugal

Our best United Airlines deals on St. Louis to Portugal flight tickets

United Airlines

Feb 23

STL4:39 pmLambert-St Louis

10h 51m

1 stop

OPO9:30 amPorto

Feb 26

OPO6:00 amPorto

13h 45m

1 stop

STL1:45 pmLambert-St Louis

$718

United Airlines

Feb 23

STL4:39 pmLambert-St Louis

10h 51m

1 stop

OPO9:30 amPorto

Feb 26

OPO6:00 amPorto

13h 45m

1 stop

STL1:45 pmLambert-St Louis

$719

United Airlines

Feb 23

STL1:08 pmLambert-St Louis

14h 22m

2 stops

OPO9:30 amPorto

Feb 26

OPO6:00 amPorto

13h 45m

1 stop

STL1:45 pmLambert-St Louis

$723

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Quickest round-trip

St. LouisPorto

STL Lambert-St Louis - OPO Porto

STLOPO

Lambert-St Louis

Tue 2/23

4:39 pm-9:30 am

1 stop10h 51m

Porto

Fri 2/26

6:00 am-1:45 pm

1 stop13h 45m

$718

St. LouisPorto

STL Lambert-St Louis - OPO Porto

STLOPO

Lambert-St Louis

Tue 2/23

4:39 pm-9:30 am

1 stop10h 51m

Porto

Fri 2/26

6:00 am-1:45 pm

1 stop13h 45m

$719

St. LouisLisbon

STL Lambert-St Louis - LIS Lisbon Humberto Delgado

STLLIS

Lambert-St Louis

Mon 12/7

4:05 pm-9:20 am

1 stop11h 15m

Lisbon Humberto Delgado

Wed 12/23

5:00 am-1:45 pm

1 stop14h 45m

$731

St. LouisLisbon

STL Lambert-St Louis - LIS Lisbon Humberto Delgado

STLLIS

Lambert-St Louis

Mon 12/7

10:06 am-9:00 am

2 stops16h 54m

Lisbon Humberto Delgado

Wed 12/23

11:15 am-8:43 pm

2 stops39h 28m

$736

St. LouisLisbon

STL Lambert-St Louis - LIS Lisbon Humberto Delgado

STLLIS

Lambert-St Louis

Mon 2/22

9:20 am-10:40 am

2 stops19h 20m

Lisbon Humberto Delgado

Fri 2/26

10:55 am-9:23 pm

2 stops40h 28m

$797

St. LouisLisbon

STL Lambert-St Louis - LIS Lisbon Humberto Delgado

STLLIS

Lambert-St Louis

Mon 11/30

4:05 pm-9:20 am

1 stop11h 15m

Lisbon Humberto Delgado

Tue 3/2

12:50 pm-5:34 pm

2 stops34h 44m

$818

St. LouisLisbon

STL Lambert-St Louis - LIS Lisbon Humberto Delgado

STLLIS

Lambert-St Louis

Fri 1/29

11:00 am-1:30 pm

2 stops20h 30m

Lisbon Humberto Delgado

Wed 2/3

5:00 am-1:45 pm

1 stop14h 45m

$818

St. LouisLisbon

STL Lambert-St Louis - LIS Lisbon Humberto Delgado

STLLIS

Lambert-St Louis

Fri 1/29

11:00 am-1:30 pm

2 stops20h 30m

Lisbon Humberto Delgado

Wed 2/3

5:00 am-9:49 pm

2 stops22h 49m

$823

St. LouisLisbon

STL Lambert-St Louis - LIS Lisbon Humberto Delgado

STLLIS

Lambert-St Louis

Sun 11/29

7:00 am-8:00 am

1 stop19h 00m

Lisbon Humberto Delgado

Thu 3/4

10:00 am-9:21 pm

1 stop17h 21m

$835

St. LouisLisbon

STL Lambert-St Louis - LIS Lisbon Humberto Delgado

STLLIS

Lambert-St Louis

Sun 11/29

7:00 am-8:00 am

1 stop19h 00m

Lisbon Humberto Delgado

Tue 3/2

10:00 am-9:21 pm

1 stop17h 21m

$835

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from St. Louis to Portugal

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

What is the cheapest month to fly to Portugal?

The cheapest month to fly to Portugal from St. Louis is in February. Flight prices, which tend to average around $520, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of February, then book flights to Portugal from St. Louis during April instead. Flights to Portugal in April, while not as cheap as those in February, still average around $609.

How far in advance should I book a flight from St. Louis to Portugal?

You are more likely to see cheaper flights to Portugal from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Portugal for around $1,142 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Portugal from St. Louis for as low as $594 on momondo.

Can stopping save me money on St. Louis to Portugal flights?

You could potentially save up to 25% on your flight if you consider stops on a St. Louis to Portugal flight.

Cheap St. Louis to Portugal flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Portugal

Best Price Found	$354
Fastest flight time	10h 51m
Direct flights	None

The best one-way flight to Portugal from St. Louis in the past 72 hours is $354. The best round-trip flight deal from St. Louis to Portugal found on momondo in the last 72 hours is $718.

The fastest flight from St. Louis to Portugal takes 10h 51m

There are no direct flights from St. Louis to Portugal. There are no popular flight routes from St. Louis to Portugal.

Search flight deals

Frequently asked questions about flying from St. Louis to Portugal

When did momondo last update prices for flights from Lambert-St Louis Airport to Portugal?
Prices for flights from Lambert-St Louis Airport to Portugal are refreshed on a daily basis.
How many operators does momondo search for flights from Lambert-St Louis Airport to Portugal?
The number of operators available for flights from Lambert-St Louis Airport to Portugal is 6 as of November 2026.
How old do you have to be to fly from Lambert-St Louis Airport to Portugal?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to Portugal.
What documentation or ID do you need to fly to Portugal?
The travel and health documents you'll need for your trip to Portugal may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Portugal. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

Best airlines flying from St. Louis to Portugal

Compare and see reviews for airlines that fly from St. Louis to Portugal with momondo

Airline	Rating	Free Cancellation	Price
Lufthansa	PriceFrom $493	Free Cancellation	Rating 6.8 8,294 reviews	Search Lufthansa flights
American Airlines	PriceFrom $502	Free Cancellation	Rating 7.0 12,224 reviews	Search American Airlines flights
Delta	PriceFrom $558	Free Cancellation	Rating 7.8 8,708 reviews	Search Delta flights
British Airways	PriceFrom $574	Free Cancellation	Rating 6.7 8,280 reviews	Search British Airways flights
United Airlines	PriceFrom $588	Free Cancellation	Rating 7.3 10,478 reviews	Search United Airlines flights
Air Canada	PriceFrom $649	Free Cancellation	Rating 7.1 11,888 reviews	Search Air Canada flights

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Portugal?

It is quick and easy to find St. Louis to Portugal flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Portugal that suits you.

Can I find flights from St. Louis to Portugal with flexible booking policies on momondo?

Yes. momondo allows you to filter the results for St. Louis to Portugal flights to just show those with flexible booking policies.

How can momondo help me find flights from St. Louis to Portugal?

Once you have performed a search for St. Louis to Portugal flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.

I’m not ready to book a flight from St. Louis to Portugal right now. Can momondo alert me if prices change?

If you are not ready to book a flight from St. Louis to Portugal now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Portugal and let you know when they change.

An easier way to manage your Portugal trip

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Popular cities

Other flights from St. Louis

Other flights to Portugal

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Cabin classes

Complete your trip

Feeling lucky

Popular cities in Portugal

Flights to Lisbonfrom $358

Flights to Portofrom $516

Flights to Funchalfrom $524

Flights to Farofrom $553

Flights to Ponta Delgadafrom $439

Flights to Lajesfrom $310

Flights to Hortafrom $433

Flights to Pico Islandfrom $585

Flights to Porto Santofrom $889

Flights to Velasfrom $693

Cheap flights from St. Louis to Portugal from $354

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Portugal departing on 3/13. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.

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Air Canada flights from St. Louis to Portugal

Our best Air Canada deals on St. Louis to Portugal flight tickets

United Airlines flights from St. Louis to Portugal

Our best United Airlines deals on St. Louis to Portugal flight tickets

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See travel insights to Portugal from

How to get the cheapest flight ticket from St. Louis to Portugal

What is the cheapest month to fly to Portugal?

How far in advance should I book a flight from St. Louis to Portugal?

Can stopping save me money on St. Louis to Portugal flights?

What is the cheapest airline that flies from Lambert-St Louis to Portugal?

What airlines fly to Portugal?

Cheap St. Louis to Portugal flight deals and tips

Best Price Found

Fastest flight time

Direct flights

Frequently asked questions about flying from St. Louis to Portugal

Best airlines flying from St. Louis to Portugal

Compare and see reviews for airlines that fly from St. Louis to Portugal with momondo

Why use momondo?

An easier way to manage your Portugal trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Portugal

Popular cities in Portugal

Popular flights according to clicks in the last 7 days on momondo

St. Louis flight routes

According to popular flight searches on momondo this year

Portugal flight routes

According to popular flight searches on momondo this year

Fly your favorite airline to Portugal

Airlines are sorted and displayed according to clicks in the past 7 days on momondo

Cabin classes currently available on flights to Portugal

List of cabin classes available on flights landing in Portugal. Availability may vary depending on flight origin and airline.

Complete your trip to Portugal

Explore popular destinations other users love

According to popular flight searches on momondo this year