$434 Find Cheap Flights from St. Louis to Portugal

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 Portugal departing on 7/28. 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
1 adult, Economy, 0 bags

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Cheap Flights from St. Louis to Portugal

Cheapest round-trip prices found by our users on KAYAK in the last 72 hours
Lisbon
Lisbon2 stops$802
Porto
Porto1 stop$829
Lisbon
Lisbon2 stops$802
Porto
Porto1 stop$829

Book Cheap St. Louis to Portugal Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Portugal 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 for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from St. Louis to Portugal

Thu, Oct 15 - Thu, Oct 22
Delta Logo
2:18 pm - 2:55 pm
STL
-
LIS
18h 37m
2 stops
Delta Logo
5:35 am - 8:37 pm
LIS
-
STL
21h 02m
2 stops
$802Delta
Thu, Oct 15 - Thu, Oct 22
Multiple Airlines Logo
6:51 pm - 4:05 pm
STL
-
LIS
15h 14m
2 stops
Multiple Airlines Logo
12:30 pm - 11:41 pm
LIS
-
STL
17h 11m
2 stops
$803Multiple Airlines
Thu, Oct 15 - Thu, Oct 22
Delta Logo
5:30 pm - 6:45 pm
STL
-
LIS
19h 15m
2 stops
Delta Logo
5:35 am - 8:37 pm
LIS
-
STL
21h 02m
2 stops
$807Delta
Thu, Oct 15 - Thu, Oct 22
Multiple Airlines Logo
6:51 pm - 4:05 pm
STL
-
LIS
15h 14m
2 stops
Multiple Airlines Logo
11:05 am - 11:41 pm
LIS
-
STL
18h 36m
1 stop
$809Multiple Airlines
Thu, Oct 15 - Thu, Oct 22
Finnair Logo
12:43 pm - 11:25 pm
STL
-
LIS
28h 42m
2 stops
Finnair Logo
6:35 am - 11:25 pm
LIS
-
STL
22h 50m
2 stops
$810Finnair
Sun, Oct 4 - Wed, Oct 21
United Airlines Logo
7:30 am - 9:45 am
STL
-
OPO
20h 15m
1 stop
United Airlines Logo
12:45 pm - 4:26 pm
OPO
-
STL
33h 41m
2 stops
$829United Airlines
Tue, Oct 6 - Tue, Oct 20
United Airlines Logo
7:30 am - 7:00 am
STL
-
OPO
17h 30m
2 stops
United Airlines Logo
12:15 pm - 2:18 pm
OPO
-
STL
32h 03m
2 stops
$832United Airlines
Mon, Oct 5 - Tue, Oct 20
United Airlines Logo
9:23 am - 9:45 am
STL
-
OPO
18h 22m
2 stops
United Airlines Logo
12:15 pm - 2:18 pm
OPO
-
STL
32h 03m
2 stops
$833United Airlines
Thu, Oct 15 - Fri, Oct 23
Delta Logo
5:30 pm - 6:45 pm
STL
-
LIS
19h 15m
2 stops
Delta Logo
5:00 am - 5:06 pm
LIS
-
STL
18h 06m
2 stops
$836Delta
Sat, Oct 10 - Fri, Nov 13
Air Canada Logo
6:49 pm - 9:20 am
STL
-
LIS
32h 31m
2 stops
Air Canada Logo
11:20 am - 2:18 pm
LIS
-
STL
32h 58m
2 stops
$857Air Canada
Booking Insights

KAYAK's insights & trends for St. Louis to Portugal flights

Get data-powered insights and trends into flights from St. Louis to Portugal 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 Portugal?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to Portugal, 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 Portugal is March, when tickets cost $458 (return) on average. On the other hand, the most expensive months are June and July, when the average cost of round-trip tickets is $791 and $754 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from St. Louis to Portugal, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from St. Louis to Portugal, you should book around 1 week before departure. For the absolute cheapest price, our data suggests you should book 1 week before departure.

Good to know

Low seasonFebruary
Cheapest flight$434
Best time to beat the crowds with an average 39% drop in price.
Most popular time to fly with an average 17% increase in price.
Flight from St. Louis to Lisbon

FAQs - booking Portugal flights

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

    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 Portugal.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from St. Louis to Portugal 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 Portugal?

    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 from St. Louis to Portugal with an airline and back with another airline.

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

    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 from St. Louis to Portugal up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top 5 airlines serving from St. Louis to Portugal

 
Need help choosing which airline to fly with from St. Louis to Portugal? 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.
7.9
DeltaOverall score based on 8467 reviews
8.1Boarding
7.8Entertainment
7.9Comfort
8.5Crew
7.2Food
Airline reviews

The agent at check in and at the gate were less than thrilled to be at work. I'm not a fan of Kayak's placement on the plane. I got put in the middle seat and none of my preferences were used.

4.0 OkayBradley, Apr 2026
RDU - ATL
Read more Delta reviews

The agent at check in and at the gate were less than thrilled to be at work. I'm not a fan of Kayak's placement on the plane. I got put in the middle seat and none of my preferences were used.

In ATL they have two sets of departure screens. Follow what is on your airline's departure board - the ATL Airport Authority departure board had completely incorrect details about the gate assignment for my flight, which would have made me miss boarding.

Flight was delayed it was hot while sitting on the plane, one engine was working on the plane until they had to do some jimmy rigging down the runway in order for the other engine to charge up. It was ridiculous

The flight was very good and the staff was very friendly and helpful!

The only thing I would say is we tried to get on a standby earlier flight, but with our fair we couldn’t. That seems senseless to leave with open seats..

Very easy to use and convenient, you can perform any action within the same portal

In a world of delays, Delta was on time both ways! Boarding was fast and efficient. Staff was friendly. AND wifi worked.

WiFi didn’t work. Flight delayed 3 hours Crew members were illiterate Seat lean back did not work.

Flight was delayed, we could have been notified earlier and in a consistent manner. App was not refreshing for another passenger to get the latest flight status. We could have stayed and waited at the hotel instead of waiting at the airport had we known the flight was going to delayed for more than 5 hours. The toilet is too tight, and needs to be cleaned more frequently (every hour). The entertainment screen froze, the touch screen not responding to touch. We were upgraded to comfort, it is more comfortable than regular economy seats.

Everything was great. The only issue is unfixable. Seats are too small. 😁🤪

Booked through Kayak Business, had a seat in middle and towards back due to booking rate, not comfortable.

Was great in general, try to respect time and excuses when slight changes have been made, appreciated!

A long delay. Don't travel late in the day.

Super friendly with lots of drink options an entertainment. Friendly crew.

Standard flight with a drinks and a snack- overall very quick flight. The flight attendants were very strict, bordered on rude.

Outstanding service, efficient & friendly crew, flight was safe, comfortable & on time

United Airline crews were very friendly and very attentive. 12 hours flight was gone like in a shorter one.

Delayed - weather wasn't bad at either end. Also sat on tarmac in ORD.

Food was surprisingly delicious. Space in the seat is horrible when the seating front is reclined. Movie offerings were terrible. Crew was friendly and helpful.

They told us yesterday APR21st that they were cleaning the plane and we got delayed. After that they said they didn't had any crew for the flight so they cancelled the flight till next day.

I would like a refund for the extra cost the seat I paid for. An oversized person sat next to me and I couldn’t fit on my seat and had to move to another seat.

Boarding gate at LAX was too crowded—two gates next to one another

The flight was delayed about an hour for a maintenance specialist to approve the maintenance repair

This flight was delayed but it worked in my favor because my Atlanta to Dallas flight was delayed.

This was a hard flight. 3 delays out of OKC (1 on the Tarmac). Delay in Atlanta coming to Dallas. total travel time was the equivalent of driving from OKC to Atlanta.

Like: flights are on time, good boarding process Can improve: planes are old, improve entertainment and make space more comfortable

Had to wait for a gate for a long time, then waited on the run way for a long time before leaving. The actual flights part was good.

The airplane was an old model, the overhead didn’t have enough room for people’s items and made boarding and boarding disappointing and stressful. Crew allowed passengers to bring more than the permitted baggage sizes.

Flying in the United States with the major airlines has become so underwhelming. A 2-3hr flight in most other parts of the world with the major carriers of the area comes with newer, CLEANER aircraft and significantly better in flight service in terms of both staff attitude and a actual meal service.

On time departure and early arrival. Flight attendant very nice.

shittiest airline in the hemisphere. To improve - start thinking you're flying people, not cattle

Easy boarding, inflight refreshments came on time and comfortable seat

It was good that our flight left early. It was a nice smooth flight and landing.

All good……but luggage didn’t make it on the airplane. Had to wait 3 days. Was a bummer.

Small suitcase used for carryon the last time was refused by boarding crew this time. Appears to be at the discretion and mood of the person on the day. Flight was only half booked, there would have been no problem with space.

It was a problem because there was a delay where we sat before taking off from newark,then when landed in Toronto we sat on tarmac and they wouldn't let us out for a long period of time. When we finally were released to the airport in Toronto the attendant scanned our boarding pass that we were here for our connection to Brazil. We ran all the way to the gate and they said at the gate the door is shut so we can not let you on the plane. We explained that we were checked in by the attendant when we arrived at Toronto airport to go to Brazil and they should not have shut the door. We were ignored at the gate

Flight home was delayed multiple times, did not get home until 2am

the check-in lady at ORD was extremely rude and unprofessional. very disappointed as it was supposed to be a celebration for my wife's birthday and it really put a damper on things. if i wanted to be treated like trash, i would have flown Economy! (as opposed to business class)

My original flight was cancelled and then rebooked four hours later on a recovery flight, but I was checked in as stanby and had no seats so as a family of four we were concerned about not being seated altogether. Our flight then got delayed by another 1.5 hours and when seats were assigned at the gate, three of the four of us were together and we could get my wife closer, they offered no assistance.

Rude flight attendants with poor service. Worst first class experience I’ve ever had.

I upgraded to the business class cabin. It was the poorest business class I have ever experienced. No access to any business lounge in Tampa airport. Seats are not comfortable. I had a window seat and had to step/crawl over the next seat. Food was mediocre and service below average for business class. Bathroom location was ridiculous. No place to wait. I cannot believe I paid this kind of money and will never fly Lufthansa Discover again. They really should reimburse me somehow.

Boarding was disorganized. The door to one to the toilets wouldn’t lock. The plane was shockingly cramped, and clearly used for domestic flights due to the menus for items to sell domestic travelers. United should be ashamed of its small seats, tiny unclean toilets, and money grubbing stance toward services, compared to Lufthansa, Emirates, and most international carriers United is awful.

Was never allowed on and not refunded the full amount of the ticket plus charged a $300 processing fee.

Terrible. Lost our luggage for 4 days. Did not advise passengers there was a strike in Barcelona Airport and had zero personnel on hand at airport to advise passengers on where to go to file claims. We had to fend for ourselves. No assistance at all other than an online claims submission process that we had to find out about on our own.

Lufthansa cancelled our flight from Los Angeles to Naples Italy on March 10 for scheduled flight on March 12 Very stressful experience trying to arrange alternatives. Will never fly again with Lufthansa

Everything could have been better. What needed to be wrong with United went wrong

The staff was bit rude when I asked for an extra drink after one beer, asked for one wine glass.

Very good, i got two seats for myself, and was comfortable with the blanket i got

I hated the FRA Airport. Confusing signage, including the path to Immigration and Security It seems that the airport grew haphazardly over the years. I have been through multiple WW Hubs with much better experiences.

Economy Priority seats are extremely uncomfortable. There is no way to escape the boxed in feeling, particularely because the distance between to rows are too short, the hard edge of the front row is keeping legs confined. There is no elevated place to put your feet. I am of average, European size.

Everything you need to know for your flight from St. Louis to Portugal

Information on your arrival and departure airports