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

Prices for flights from Porto Airport to Lambert-St Louis Airport refresh daily.

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

The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Porto Airport to Lambert-St Louis Airport.

What documentation or ID do you need to fly to Lambert-St Louis Airport?

The necessary travel and health documents for your Lambert-St Louis Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

$859 Cheap Flights from Porto to St. Louis in 2025/26

1 adult

0 bags

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6:00 am - 9:13 pm

OPO

STL

21h 13m2 stops

11:20 am - 2:55 pm

STL

OPO

21h 35m2 stops

$859United Airlines

Thu, Jan 22 - Mon, Jan 26

6:00 am - 9:13 pm

OPO

STL

21h 13m2 stops

11:20 am - 11:40 am

STL

OPO

18h 20m2 stops

$860United Airlines

Thu, Jan 22 - Mon, Jan 26

6:00 am - 9:13 pm

OPO

STL

21h 13m2 stops

11:20 am - 2:55 pm

STL

OPO

21h 35m2 stops

$861United Airlines

Thu, Jan 22 - Mon, Jan 26

United Airlines flights from Porto to St. Louis

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

United Airlines

Jan 22

OPO6:00 amPorto

21h 13m

2 stops

STL9:13 pmLambert-St Louis

Jan 26

STL11:20 amLambert-St Louis

21h 35m

2 stops

OPO2:55 pmPorto

$859

Find similar

United Airlines

Jan 22

OPO6:00 amPorto

21h 13m

2 stops

STL9:13 pmLambert-St Louis

Jan 26

STL11:20 amLambert-St Louis

18h 20m

2 stops

OPO11:40 amPorto

$860

Find similar

United Airlines

Jan 22

OPO6:00 amPorto

21h 13m

2 stops

STL9:13 pmLambert-St Louis

Jan 26

STL11:20 amLambert-St Louis

21h 35m

2 stops

OPO2:55 pmPorto

$861

Find similar

Fly from

Fly to

Route

Depart

Return

Price

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Thu 1/22

6:00 am-9:13 pm

2 stops21h 13m

Lambert-St Louis

Mon 1/26

11:20 am-2:55 pm

2 stops21h 35m

$859

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Thu 1/22

6:00 am-9:13 pm

2 stops21h 13m

Lambert-St Louis

Mon 1/26

11:20 am-11:40 am

2 stops18h 20m

$860

PortoSt. Louis

OPO - STL

OPOSTL

Porto

Thu 1/22

6:00 am-9:13 pm

2 stops21h 13m

Lambert-St Louis

Mon 1/26

11:20 am-2:55 pm

2 stops21h 35m

$861

Flights are sorted by cheapest round-trip flights first.

Sorted by cheapest first

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

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

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

You could potentially save up to 28% on your flight if you consider stops on a Porto to St. Louis flight.

When to book flights from Porto to St. Louis

Are you open to changing your travel dates? Check out the ideal times to fly from Porto to St. Louis according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Porto to St. Louis (OPO to STL) flight deals and tips

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

Fastest flight time	21h 13m
Direct flights	None

The fastest flight from Porto to St. Louis takes 21h 13m

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

Search flight deals

How far is Porto to Lambert-St Louis by plane?
There are 4156.0 mi between Porto and Lambert-St Louis. A reasonable flight in good conditions will take 21h 13m.
When did momondo last update prices for flights from Porto Airport to Lambert-St Louis Airport?
Prices for flights from Porto Airport to Lambert-St Louis Airport refresh daily.
How old do you have to be to fly from Porto Airport to Lambert-St Louis Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Porto Airport to Lambert-St Louis Airport.
What documentation or ID do you need to fly to Lambert-St Louis Airport?
The necessary travel and health documents for your Lambert-St Louis Airport trip may vary depending on your travel plans and individual circumstances. Generally, you should have various documents, such as a national ID card or driver's license and a passport that is valid for six months beyond your scheduled arrival date. We recommend seeking advice from your airline or a trusted third party, such as IATA.

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Why use momondo?

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

It is quick and easy to find Porto to St. Louis 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 St. Louis that suits you.

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

Yes. All flights to St. Louis from Porto on momondo can be compared and filtered by various policies on offer, including flexible booking.

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

momondo helps you find the best flight between Porto and St. Louis by providing filters to narrow your choice of flights to those matching your criteria. You can select flights based on numerous factors such as price, departure and landing times, airport and airline.

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

Of course. momondo tracks the price of Porto to St. Louis flights. All you need is a valid email address and we will do the rest; it is that quick and easy.