$392 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 9/29. 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$729
Porto
Porto2 stops$913
Lajes
Lajes1 stop$1,593
Lisbon
Lisbon2 stops$729
Porto
Porto2 stops$913
Lajes
Lajes1 stop$1,593

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

Fri, May 1 - Sun, May 10
British Airways Logo
5:21 pm - 6:00 pm
STL
-
LIS
18h 39m
2 stops
British Airways Logo
7:20 am - 7:29 pm
LIS
-
STL
18h 09m
2 stops
$729British Airways
Mon, Aug 17 - Wed, Aug 26
Scandinavian Airlines Logo
3:42 pm - 8:40 pm
STL
-
LIS
22h 58m
2 stops
Scandinavian Airlines Logo
6:15 pm - 11:37 pm
LIS
-
STL
35h 22m
2 stops
$798Scandinavian Airlines
Mon, Apr 20 - Mon, Apr 27
Delta Logo
5:59 pm - 2:55 pm
STL
-
LIS
14h 56m
2 stops
Delta Logo
5:00 am - 11:13 pm
LIS
-
STL
24h 13m
2 stops
$819Delta
Mon, Aug 17 - Wed, Aug 26
United Airlines Logo
12:10 pm - 9:20 am
STL
-
LIS
15h 10m
1 stop
United Airlines Logo
11:25 am - 4:31 pm
LIS
-
STL
35h 06m
2 stops
$850United Airlines
Sat, May 9 - Sat, May 16
Delta Logo
11:25 am - 11:15 am
STL
-
LIS
17h 50m
2 stops
Delta Logo
5:00 am - 4:43 pm
LIS
-
STL
17h 43m
2 stops
$853Delta
Mon, Aug 17 - Wed, Aug 26
Air Canada Logo
12:10 pm - 9:20 am
STL
-
LIS
15h 10m
1 stop
Air Canada Logo
11:25 am - 6:42 pm
LIS
-
STL
13h 17m
1 stop
$864Air Canada
Sun, Aug 16 - Fri, Sep 11
Air Canada Logo
12:10 pm - 9:20 am
STL
-
LIS
15h 10m
1 stop
Air Canada Logo
1:00 pm - 2:00 pm
LIS
-
STL
31h 00m
1 stop
$869Air Canada
Thu, Oct 1 - Tue, Oct 13
Multiple Airlines Logo
1:30 pm - 10:30 am
STL
-
OPO
15h 00m
2 stops
Multiple Airlines Logo
6:15 am - 5:06 pm
OPO
-
STL
16h 51m
2 stops
$913Multiple Airlines
Sat, Apr 25 - Sat, May 2
Multiple Airlines Logo
5:59 pm - 3:25 pm
STL
-
OPO
15h 26m
2 stops
Multiple Airlines Logo
5:00 am - 4:42 pm
OPO
-
STL
17h 42m
2 stops
$1,003Multiple Airlines
Mon, Aug 31 - Sat, Sep 12
United Airlines Logo
4:52 pm - 9:45 am
STL
-
OPO
10h 53m
1 stop
United Airlines Logo
10:15 am - 3:38 pm
OPO
-
STL
35h 23m
2 stops
$1,025United Airlines
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 April, when tickets cost $587 (return) on average. On the other hand, the most expensive months are December and June, when the average cost of round-trip tickets is $2,683 and $1,284 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$392
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 Porto

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 8383 reviews
8.1Boarding
7.9Comfort
8.5Crew
7.8Entertainment
7.2Food
Airline reviews

We departed and landed early which was a nice surprise. The boarding process was slow.

10.0 ExcellentBrittany, Apr 2026
DAL - ATL
Read more Delta reviews

We departed and landed early which was a nice surprise. The boarding process was slow.

N Everything was perfect from boarding to assistance to baggage in Tampa

Subpar. The seating on the plane is almost unbearable. We are literally touching and/or sitting on each other which is totally unacceptable and shameful. Pilots and crew was very accommodating and friendly.

The boarding was organized and informative but the plane was tight meaning that you were sitting on one another and extremely uncomfortable. It’s disappointing that can’t have common seating comfort on the plane.

Loved the crew! Sucks that we went from 1 hour and 8 minute layover to a 3 hour layover. But weather sucks like that.

I was told that they needed to check my bag at the gate and to pick it up at the gate in Richmond. No big deal. I know they can't control the weather, but we flew around RIC for 45 minutes to avoid the storm and were 25 minutes late leaving as well. Once we landed, we were told to go to baggage claim to pick up our luggage. I went to bathroom, paid for parking, and went to the assigned baggage claim location. United flight people came down with us as well. They got their luggage immediately. Next, South West people came down about 10 minutes later. They got their luggage next. We finally got our luggage around 30 minutes in waiting. Was not a wonderful experience. No reflection on Delta, but the ground crew was lousy at best.

Everything could have benn better. Short fly, no food, no entertainment and no wifi.

Flight delayed. Air broken. Cabin was hot enough to pass out. Delta shuttle’s becoming worse and worse.

my mom urmila patel needed a wheelchair which was not available on the curbside. she needed to walk almost 50 meters inside (at the risk of falling) and then had to wait in line to get a wheelchair (this is not ok). Once obtained she had to seat in it for 30-45 minutes for someone to take her in thru the checkin process (which was fairly smooth and easy). the lady who helped her with her checkin process was very courteous and helpful

On the return flight, flight attendant Britt went out of her way to inform passengers that several of us had tight connections.

Flight left on time, arrived early, pleasant staff provided water, coffee, etc. access to bathrooms was reasonable and were well maintained. blankets were available, lots of entertainment options. LUGGAGE SERVICE WAS GREAT. I got my one checked bag quickly and was able to make a bus connection for a 2 hour bus ride saving me from waiting another 1.5 hours.

The boarding process was straightforward. One pertinent observation regarding all boarding procedures is that if an individual requires assistance or possesses a special status and is part of preboarding, it is advisable to limit the number of passengers who can preboard with them, rather than the entire, sometimes large, companion groups. The seats are uncomfortable, and the entertainment options are significantly inferior compared to other airlines. During the snack service, I requested an additional bag of snacks, but my request was denied. Initially, the flight attendant agreed to my request.becoming a strange accurate moment. The flight duration was four hours.

The flight was officially delayed 3 times, and was actually later than that. Combined, it was a 3 hour delay, but there was no recognition (miles, voucher, etc). The crew seemed stressed. The captain sounded nervous in his announcements. The flight itself was smooth and uneventful.

United didn’t even try to hold the flight for me. They knew I had a tight connection and when I arrived at the gate less than 10 mins after final boarding the flight had already gone. The gate agent wasn’t even notified that I was on my way. She was told I wasn’t at the airport

Great until we got to FRA. The next trip leg we were put in Business Class where seats had minimal padding!!!! They were awful and United Airlines needs to have their Lufthansa partner up their game or I won’t fly with them again!!

I had a good time. However, I paid for the wifi and it was in and out the whole flight.

one staffer was frustrated (it happen); the flight was late and the pilot mentioned they'll make amend but the snacks were the same, other than that the aircraft was clean and everything went smooth, no complaints

The wheelchair service is useless. They live you in different spots, not tell you anything just wait. I waited 30 minutes in Frankfurt when decided to walk the 25 minutes distance. In Budapest nobody came.

It was perfect! I've never flown with United before, but I definitely will in the future

I had a cancelled flight because of technical issues going to my destination, and a delayed flight coming home. All told it wasn’t a total bust.

there are no options s for snack besides cookies would ve nice to have a salty option n

We did not have enough time to make our connecting flight. As a result, we were put onto a different airline for our second leg. The different airline was NOT comparable to British Airlines, and our arrival was significantly delayed. The actual flight on BA was amazing.

We left at 1030 am pacific from LA and supposed to land at 7 pm Eastern in NY. They made a detour, stopped in Philadelphia and didn’t land till 1130 PM Eastern!!! Worst flight experience with no pilot communication with no explanation as to what was going on. Everyone was very frustrated to say the least.

Going non stop to lax like I paid for. Not stopping in MCI for gas. Too long of delays

Human interaction. Thought there would be more service-even a smile would have been nice.

It was canceled at the last minute. While I was literally at the airport. Messed my entire trip up.

Seat was VERY uncomfortable. Flight was delayed and then boarded slowly. The crew was super helpful with boarding and supporting maximizing the luggage in the overhead.

Crew at the gate was very crabby and not at all polite. The plane was very hot the entire flight. And the seat cushion was very worn out.

Incoming flight was delayed, delaying boarding. It then took 30 mins to take off. Took 20 mins to get to a gate because they changed the gate last minute, crew weren’t ready so there was no one staffed to work the jet bridge. Boarding was so disorganized as is usual with American because everyone just stands around the gate regardless of boarding group.

I cancelled my ticket less than 24 hours deadline but I didn’t get refunded.

I bought a ticket from Kayak. When I got to the airport, the was no ticket. I had to pay 5X to get to my destination. No response received from Kayak. I will NEVER use them again.

My wallet was stolen while I was sleeping on the plane.

Good boarding but extremely cold temperature in both flights (60 F!).

The whole plane smelled and felt old. The seats were very uncomfortable. Multiple delays. Extra fees.

Very rude gate attendants in San Francisco who didn’t let me bring my little carry on (smaller than usual size) and after boarding I realized that there still were a lot of overhead compartment space (like a full section available in some spots). That made me lose 30 minutes at my destination at 1am and it could have broken something fragile that I had in it

The most uncomfortable flight I’ve ever been on. I’m only 5,4” and barely had enough room to exist, couldn’t even fully relax my shoulders. Not sure why they bother with snacks. Half a coke and a single cookie?? Wow. Purchasable food looked gross too. Remember when airlines used to treat you like a human being?

Departed Palm Springs over an hour late because there’s only one gate, and it has always delayed by the arriving and departing flight to Toronto and the arriving flight from Vancouver.

I checked a bag and there was only one agent to assist all customers with any issues.

I want to thank Carlos at the Miami AC desk - he was amazing and went over and above to help us out. Thank you Carlos and all the best to you!!! You made our faith in AC feel great! Sincerely, David Cubitt

Flight was canceled due to mechanical issues. After a considerable wait in the queue, Air Canada customer service was very helpful to get us on another flight. I am disappointed to report our rescheduled flight is for three days from now. Three days of extra expenses and inconvenience is unacceptable.

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.

Terrible. Both flights were significantly delayed, no luggage, made me check my small bag when many, many others had much larger carry-ons, not even a bottle of water . . . I will not fly Discover Airlines again.

I was deceived on the Kayak site expecting a ticket, but instead finding a "standby" reservation. When I tried to change the ticket, I paid almost twice the price of the original ticket. Then, the airline refused to give me the reserved seat I had chosen and paid for. I think I deserve a refund for this leg of my trip because I was doubly charged and did not receive what I had paid for. I put in a complaint with Lufthansa because the ticket was sold originally sold as a flight they listed. Someone here needs to take responsibility.

Excellent service; they helped me reschedule so I can fly in an earlier flight

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

Information on your arrival and departure airports