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STL - OPO

$529 Find cheap flights from St. Louis to Porto

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Porto departing on 7/24. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
0 bags
Tue 5/28
Tue 6/4

Search hundreds of travel sites at once for deals on flights to Porto

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Porto, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from St. Louis to Porto, as well as popular online travel agencies
In the last 7 days travelers have searched 43,623,357 times on KAYAK, and here is why:

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Cheap flight deals from St. Louis to Porto (STL-OPO)

Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Porto that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices and deals for you by selecting your travel dates.
Choose your dates
5:05 pm - 3:40 pmSTL-OPO
16h 35m2 stops
9:15 am - 11:39 pmOPO-STL
20h 24m2 stops
$764KLM
Find Deal
Tue, Aug 20 - Tue, Aug 27
10:45 am - 11:40 amSTL-OPO
18h 55m2 stops
12:25 pm - 9:31 pmOPO-STL
38h 06m2 stops
$853American Airlines
Find Deal
Tue, Oct 1 - Wed, Oct 30
2:05 pm - 3:30 pmSTL-OPO
19h 25m2 stops
11:25 am - 1:08 pmOPO-STL
31h 43m2 stops
$897Delta
Find Deal
Sun, Sep 8 - Tue, Sep 24
6:00 pm - 3:40 pmSTL-OPO
15h 40m2 stops
11:25 am - 1:08 pmOPO-STL
31h 43m2 stops
$910Delta
Find Deal
Mon, Sep 9 - Thu, Sep 19
8:50 am - 9:45 amSTL-OPO
18h 55m2 stops
6:00 am - 2:55 pmOPO-STL
13h 55m1 stop
$922United Airlines
Find Deal
Tue, Oct 1 - Wed, Oct 30
6:02 am - 9:45 amSTL-OPO
21h 43m1 stop
6:00 am - 2:55 pmOPO-STL
13h 55m1 stop
Tue, Oct 1 - Wed, Oct 30
4:20 pm - 3:55 pmSTL-OPO
17h 35m2 stops
8:35 pm - 8:15 pmOPO-STL
29h 40m2 stops
$1,033Iberia
Find Deal
Tue, Sep 10 - Wed, Sep 25
2:35 pm - 12:30 amSTL-OPO
27h 55m3 stops
6:20 pm - 10:14 pmOPO-STL
33h 54m3 stops
$1,037
Find Deal
Tue, Aug 20 - Tue, Aug 27
4:20 pm - 3:55 pmSTL-OPO
17h 35m2 stops
8:15 am - 5:14 pmOPO-STL
14h 59m2 stops
$1,142Iberia
Find Deal
Fri, Sep 6 - Sun, Sep 22
9:08 am - 6:55 amSTL-OPO
15h 47m2 stops
9:00 am - 4:07 pmOPO-STL
13h 07m1 stop
$1,152United Airlines
Find Deal
Mon, Jul 1 - Wed, Jul 10

Flights from St. Louis to Porto - Travel Insights & Trends

Get data-powered insights and trends into flights from St. Louis to Porto to help you find the cheapest flights, the best time to fly and much more.

Which airlines provide the cheapest flights from St. Louis to Porto?

The cheapest price for the route for each airline clicked by KAYAK users in the last 72 hours.
In the last 72 hours, the cheapest one-way ticket from St. Louis to Porto found on KAYAK was with United Airlines for $529. KLM proposed a round-trip connection from $764 and American Airlines from $853.

Good to know

Low season

February

High season

September

Cheapest flight

$529
Best time to beat the crowds with an average 48% drop in price.
Most popular time to fly with an average 10% increase in price.
Flight from St. Louis to Porto

When to book flights from St. Louis to Porto

Are your dates flexible? Find out the best times to travel from St. Louis to Porto based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from St. Louis to Porto

  • What is the cheapest flight from St. Louis to Porto?

    In the last 3 days, the lowest price for a flight from St. Louis to Porto was $529 for a one-way ticket and $764 for a round-trip.

  • Do I need a passport to fly between St. Louis and Porto?

    Yes, you’ll need a passport to travel to Porto from St. Louis.

  • Which airports will I be using when flying from St. Louis to Porto?

    St. Louis and Porto are both served by 1 main airport. You will leave St. Louis from Lambert-St Louis and will be arriving at Porto.

  • Which aircraft models fly most regularly from St. Louis to Porto?

    We unfortunately don’t have that data for this specific route.

  • Which airline alliances offer flights from St. Louis to Porto?

    Star Alliance, SkyTeam, and oneworld are the airline alliances operating flights between St. Louis and Porto, with Star Alliance being the most commonly used for this route.

  • Which is the best airline for flights from St. Louis to Porto, United Airlines or Iberia?

    The two airlines most popular with KAYAK users for flights from St. Louis to Porto are United Airlines and Iberia. With an average price for the route of $1,231 and an overall rating of 7.4, United Airlines is the most popular choice. Iberia is also a great choice for the route, with an average price of $1,001 and an overall rating of 7.1.

  • How does KAYAK find such low prices on flights from St. Louis to Porto?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from St. Louis to Porto.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from St. Louis to Porto?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Porto from St. Louis is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from St. Louis to Porto?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Porto with an airline and back to St. Louis with another airline. Booking your flights between St. Louis and OPO can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from St. Louis to Porto?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Porto from St. Louis up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

See more FAQs

Top airlines flying from St. Louis to Porto

 
See real verified KAYAK customer reviews for airlines flying from St. Louis to Porto. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from St. Louis to Porto? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.4
United AirlinesOverall score based on 11228 reviews
8.1crew
6.7food
7.2comfort
7.7boarding
7.1entertainment
Airline reviews

There was a group of school age passengers that were very loud and unruly with their chaperones were no where to be found.

2.0 MediocreShawne, Apr 2024IAH - MCO
Read more about United Airlines reviews

There was a group of school age passengers that were very loud and unruly with their chaperones were no where to be found.

Boarding was unorganized. They expected passengers to ask people to move their assigned seat they paid for in order to sit together. The seats even in comfort are smaller than other airlines and the flight attendants appeared not to be well prepared

The WiFi didn’t work and the seats are too close together. Very uncomfortable.

I was told we'd have a hot breakfast option in first class, so I chose not get a hot breakfast. It was a very strange meal, but the fresh fruit was very good quality. Service was excellent from ORD to ELP. No service from MBS to ORD, not even water. However, when flying American from FNT to ORD, which is a shorter flight, they at least pass out snacks and offer water.

Last minute gate change nearly caused us to miss our flight. Change was not announced or displayed in the main board at the old gate. Terrible communication. When we landed we had to wait 20 minutes because there was another plane at the assigned gate. Not the crew’s fault, but adding 20 minutes to a 45 minute flight sucked.

Nothing beats ANA customer service on my opinion. Maybe because of their Japanese culture (and food). Arigatō

So so. Terrible aircraft choice for that leg of the flight.

Due to one crew member not showing up to work, our flight was significantly delayed causing us to miss our connecting flight in Houston to Mississippi causing us to be delayed by more than 6 hours and missing our event all together. Very disappointing. All because ONE crew member called in sick. United did grant us a $15 meal voucher, which was a small but appreciated concession that I wasn’t able to use because I ordered my lunch and paid for it before applying the concession, and the staff said it was too late to use it. Ugh! We also had a TWO delay coming back from Mississippi, but that was on American Airlines and it was due to weather, so not their fault. Anyway, not at all impressed with United’s handling of our flight and the HUGE disappointment of missing our important family event for our 90 year old mother. All that money and all that stress and emotions for nothing. Having to wait the hour to bring an employee from LAX seemed like something that should not have happened. Why don’t you have a local back-up? Santa Ana is not a little airport in a rural area.

Flight delayed from Cape Town to Washington then got diverted to miami and in miami we had to fend for ourselves , im still trying to get to Shreveport now

delay several times and wait extra long to board. no entertainment service because there are problem for some rows. always encounter some delays for the last flight of the day.

good service from crew. Before the would have an option between cookies or nuts as snacks.. Now, there are only cookies. too bad. People who can not have sugar don't have a choice.

Iberia personnel on the ground is so rude. I would think twice in the future before booking another Iberia flight

I’m hoping for WiFi included. Everything else was very good

All corners have been cut and it’s a cheap experience that no longer is distinguished from most other cheap airlines

An average flight experience. For our transatlantic portion, they provided a main meal and two snacks. However, the food was not very tasty and the drinks far too small and infrequent for such a long flight. The regrettable part of the flight was that the toilets were extremely filthy. I feel this is unacceptable.

Rude security cunts. However the lady that issued my boarding ticket when I was flying back from New York was lovely & helpful!!

Appalling! The flight was delayed by 3.5 hours and the American Airlines staff at the airport where nit very helpful. Once boarded, the flight crew were unhelpful, the food was poor and the aircraft was tatty.

I called prior to flying to confirm our baggage allowance which was 5 bags. On our outbound flight thee were no problems. On the return flight we were charged for each bag totaling $400! We are working with customer service to resolve the issue.

Late boarding. Delayed departure leading to rushed connection at Madrid Barajas. Not necessarily Iberia's fault but delay loading cargo didn't help.

Everything was great, except the food, which could have been flavorful.

Book cheap flights from St. Louis to Porto

Recent one-way flight deals

 
Only flying one-way? Below are some of the best one-way flight deals from St. Louis to Porto found on KAYAK in the last 72 hours.
7/24Wed
2 stopsUnited Airlines
18h 35mSTL-OPO
$529
7/24Wed
1 stopLufthansa
25h 20mSTL-OPO
$833

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St. Louis - Porto Flights

Departure:

St. Louis (STL)United States

Destination:

Porto (OPO)Portugal

Return flight deals:

Porto - St. Louis

Cabin classes:

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