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STL - OPO

$524 Find cheap flights from St. Louis to Porto

This is the cheapest round-trip flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Porto departing on 11/3. 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
Thu 7/11
Thu 7/18

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 44,212,782 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
3:45 pm - 11:40 amSTL-OPO
13h 55m1 stop
6:00 am - 9:53 amOPO-STL
33h 53m2 stops
$524United Airlines
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Sun, Nov 3 - Fri, Nov 15
12:58 pm - 3:25 pmSTL-OPO
20h 27m2 stops
6:00 am - 9:53 amOPO-STL
33h 53m2 stops
$528United Airlines
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Mon, Nov 4 - Fri, Nov 15
3:45 pm - 11:40 amSTL-OPO
13h 55m1 stop
6:00 am - 1:55 pmOPO-STL
13h 55m1 stop
$529Lufthansa
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Sun, Nov 3 - Fri, Nov 15
10:30 am - 11:45 amSTL-OPO
19h 15m2 stops
8:20 am - 8:09 amOPO-STL
29h 49m3 stops
$538American Airlines
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Mon, Nov 4 - Tue, Nov 12
10:30 am - 7:40 amSTL-OPO
15h 10m2 stops
8:20 am - 9:15 amOPO-STL
30h 55m2 stops
$539American Airlines
Find Deal
Mon, Nov 4 - Tue, Nov 12
10:30 am - 7:40 amSTL-OPO
15h 10m2 stops
8:40 pm - 9:31 pmOPO-STL
30h 51m2 stops
$544Iberia
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Tue, Nov 5 - Mon, Nov 11
11:51 am - 10:50 amSTL-OPO
16h 59m2 stops
5:00 am - 11:35 pmOPO-STL
24h 35m2 stops
$550Delta
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Sun, Nov 3 - Wed, Nov 13
10:00 am - 10:50 amSTL-OPO
18h 50m2 stops
5:00 am - 9:31 pmOPO-STL
22h 31m2 stops
$570Delta
Find Deal
Sun, Nov 3 - Tue, Nov 12
4:45 pm - 11:40 amSTL-OPO
13h 55m1 stop
6:00 am - 1:55 pmOPO-STL
13h 55m1 stop
$579Lufthansa
Find Deal
Fri, Nov 1 - Fri, Nov 15
2:54 pm - 11:45 amSTL-OPO
15h 51m2 stops
8:20 am - 9:31 pmOPO-STL
19h 11m2 stops
$726Iberia
Find Deal
Sat, Nov 2 - Tue, Nov 12

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.

What is the cheapest month to fly from St. Louis to Porto?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for flights from St. Louis to Porto, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.
The cheapest month for flights from St. Louis to Porto is February, where tickets cost $631 on average. On the other hand, the most expensive months are June and May, where the average cost of tickets is $1,619 and $1,493 respectively.

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 Delta for $546. United Airlines proposed a round-trip connection from $524 and Lufthansa from $529.

Good to know

Low season

November

High season

June

Cheapest flight

$524
Best time to beat the crowds with an average 22% drop in price.
Most popular time to fly with an average 48% 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 $546 for a one-way ticket and $524 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?

    SkyTeam, Star Alliance, and oneworld are the airline alliances operating flights between St. Louis and Porto, with SkyTeam 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 $1,224 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 10629 reviews
8.1Crew
7.7Boarding
7.1Entertainment
6.7Food
7.2Comfort
Airline reviews

The entertainment wasn’t playing in the app or online.

4.0 OkayJohn, Jun 2024SFO - DCA
Read more about United Airlines reviews

The entertainment wasn’t playing in the app or online.

Lady was a bit rude during boarding and I was being nice to her.

Why does it have to be painful to fly long distances?

It is a modern tragedy that any airline expects you to travel for 14 hours in such discomfort and that the only way to add comfort is exorbitant prices. I was in pain by the time we landed. Shameful.

Original plane sidelined. Had to wait an hour for replacement.

Crew was very cooperative and professional. Passenger's first checked in bag should be free.

No real agent onsite helping you for missing luggage there. Not like the other airline next to UA desk, they have staff attending in their desk assisting answer/helping luggage issue, even after midnight.

Horrible, the flights kept delaying, so it is obvious that we won't be able to make it to the next connection. No easier/real agent on site to help you figure this out. UA agent on other counters refuse to assist you and direct us to use the QR code/call customer service. So inefficient and poor. While technology seems convenient, but it's not the best interest/experience for customers need help while there is active issue need assistance.

Food is very bad and entertint not too many options ... flight attendet service is not good

After the morning frenzy of 35 min wait through CLT security at 4;30 AM, it was nice to have a smooth pleasant boarding experience. This 6:30 AM flight was not full. We were able to get seated swiftly and took off promptly. Nice touch they distributed the old fashioned headsets with 8 mm jacks. Snacks were decent and arrival was uneventful.

As an advantage member I found the experience very positive

The flight from Amsterdam to Dallas was great, ok food, good service, great entertainment. But Dallas to SF was very tiring because of two hour delay inside the airplane waiting for AA paper work in 99 degrees in the sun. We had no oxygen and the pilot had to ask everyone to blast the AC because it was getting too hot inside the cabin.

We left our child’s tablet on our seat 12 B on the plane and we can’t get a hold of anyone to try to get help locating the tablet.

My flight was cancelled after a 7 hour delay. I am awaiting a refund.

Disappointing. Had to pay 70 euros for one checked bag. Transatlantic flight was cramped, not very comfortable

Ability to select seating would be nice. We were family of three and they had us seated back to back and one of us on the other side of the plane??? That is pretty goofy. Especially when tickets were placed two months in advance.

We had a seat that would not function. No Wifi or inflight entertainment was available. Food was very poor. Attendants were very accommodating and apologized for the problems.

My son and I are 193 cm tall. We had reserved and paid for seats with extra leg room towards the front of the cabin. The day of the flight, we learned that Iberia had changed aircraft. We were assigned regular seats way back in the cabin. When we landed from our first leg we spoke with agents at the gate and we were told that they couldn’t improve our seats because the flight was full.

Our flight was delayed by 2-hrs but I understand it was beyond the scope of the crew members

I am quite satisfied. The flight was on time and landed early. Staff was friendly.

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 stopsDelta
22h 02mSTL-OPO
$546
9/28Sat
1 stopUnited Airlines
10h 15mSTL-OPO
$629
7/24Wed
3 stops
21h 06mSTL-OPO
$749
7/24Wed
1 stopLufthansa
13h 55mSTL-OPO
$793

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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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