$414 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 4/14. 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
Lisbon1 stop$662
Porto
Porto2 stops$842
Lisbon
Lisbon1 stop$662
Porto
Porto2 stops$842

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

Sun, Apr 26 - Wed, May 6
Multiple Airlines Logo
9:40 pm - 11:05 pm
STL
-
LIS
19h 25m
1 stop
Multiple Airlines Logo
6:35 am - 7:33 pm
LIS
-
STL
18h 58m
2 stops
$662Multiple Airlines
Sun, Apr 26 - Wed, May 6
American Airlines Logo
8:03 pm - 5:45 pm
STL
-
LIS
15h 42m
2 stops
American Airlines Logo
6:35 am - 7:33 pm
LIS
-
STL
18h 58m
2 stops
$666American Airlines
Thu, Apr 23 - Thu, May 7
British Airways Logo
1:29 pm - 6:10 pm
STL
-
LIS
22h 41m
2 stops
British Airways Logo
11:05 am - 7:29 pm
LIS
-
STL
14h 24m
1 stop
$699British Airways
Thu, Apr 23 - Thu, May 7
British Airways Logo
1:29 pm - 6:10 pm
STL
-
LIS
22h 41m
2 stops
British Airways Logo
11:05 am - 10:19 pm
LIS
-
STL
17h 14m
2 stops
$717British Airways
Wed, Apr 15 - Tue, Apr 21
American Airlines Logo
6:29 am - 9:05 am
STL
-
LIS
20h 36m
1 stop
American Airlines Logo
8:25 am - 7:33 pm
LIS
-
STL
17h 08m
2 stops
$719American Airlines
Fri, Aug 7 - Wed, Aug 19
United Airlines Logo
8:35 pm - 7:00 am
STL
-
OPO
28h 25m
2 stops
United Airlines Logo
2:25 pm - 8:39 pm
OPO
-
STL
36h 14m
2 stops
$842United Airlines
Thu, May 7 - Tue, May 12
Delta Logo
7:01 pm - 10:00 pm
STL
-
OPO
20h 59m
2 stops
Delta Logo
5:00 am - 4:46 pm
OPO
-
STL
17h 46m
2 stops
$908Delta
Fri, Aug 7 - Wed, Aug 19
United Airlines Logo
12:23 pm - 6:55 am
STL
-
OPO
12h 32m
1 stop
United Airlines Logo
2:25 pm - 11:00 pm
OPO
-
STL
14h 35m
2 stops
$952United Airlines
Thu, Apr 16 - Thu, Apr 23
Delta Logo
1:46 pm - 3:25 pm
STL
-
OPO
19h 39m
2 stops
Delta Logo
5:00 am - 8:44 pm
OPO
-
STL
21h 44m
2 stops
$953Delta
Thu, Apr 16 - Thu, Apr 23
Lufthansa Logo
11:37 am - 11:15 am
STL
-
OPO
17h 38m
2 stops
Lufthansa Logo
4:35 pm - 1:25 pm
OPO
-
STL
26h 50m
1 stop
$966Lufthansa
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 $592 (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 $1,288 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$414
Best time to beat the crowds with an average 37% drop in price.
Most popular time to fly with an average 19% 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 8357 reviews
7.8Entertainment
8.1Boarding
8.5Crew
7.9Comfort
7.2Food
Airline reviews

The flight was delayed 90 minutes The Gate was wrong The Restroom on Aircraft was not clean There was a half used water bottle in my seat

2.0 MediocreJames, Mar 2026
BOS - LGA
Read more Delta reviews

The flight was delayed 90 minutes The Gate was wrong The Restroom on Aircraft was not clean There was a half used water bottle in my seat

Delta is always a wonderful experience. A clean plane and the crew is really friendly.

Too many people are taking up space in the overhead bins with their extra piece of luggage. Since they cannot fit their backpacks or extra luggage piece under the seat in front of them, they store it in the overheads and thus taking up room for other passengers. It wasn’t only one or two persons; more like 12 or 13 passengers.

Excellent service, I love the soft blush pink mood lighting on the 767-400ER during meal service. The overhead gasper vents on the 767-400ER were also very strong with a lot of airflow to keep me comfortable on my flight.

This was the worse experience. They delayed our flight twice and we still had to find another flight to get home sooner which was alos delayed. Also, the flight attendant named Ginny on DL9890 leaving at 4:13pm on 3/23/26 was extremely rude.

I love Delta the flight attendants were personable and the flight arrived 1/2 earlier thanks expected. All a plus. The gate agent was a bit flustered but even with that I still had a good experience. Her supervisor assisted me.

Got to fly my favorite plane, the Boeing 767-400ER, to Milan. The soft blush pink mood lighting during meal service was very beautiful and gorgeous. The service was top-notch, and our flights were on time. I highly recommend Delta.

I am still at the Airport! Delayed Delayed and Delyaed

I took seat 15A in anticipation of window seat, there is no window.

The first class flight attendant was awful to everyone. Very rude; no customer service. She should not be working in first class.

the entire flight felt off. The crew seemed uninterested and disengaged. The food service was really bad - overcooked, bland, weird food service. They actually woke us up to serve chicken wraps in the middle of the night, after dinner and before breakfast. Made no sense. Ultimately, I was glad they did though, because the breakfast had been held for so long it was inedible. Eggs, potatoes, sausage - all disgusting. We were asked to "honor" the lavatories for premium customers and stay in our own cabin: this was also strange. So people in economy didn't pay enough to use the closest toilet to them??? It's a toilet. All in all, not the experience I have come to expect from United Airlines. The return flight from Paris to SFO was better, btw.

Smooth and easy boarding, comfortable for the entire 5 hour flight, and the seat back entertainment was great! I appreciated all the features, from location info and maps, movies, the ability to connect with Bluetooth headphones, and good selection of movies. Food was good, normal airline snacks (I didn’t purchase anything)

Overall, the flight was good. Lounge access should be with all business class tickets.

They promise free wi-fi prior to boarding and then once on board you are informed you have to purchase wifi even after being a mileagePlus member.

I've been flying American mostly, and it's been very frustrating. This united flight makes me realize maybe the issue isn't flying, but the airline. United was a significantly better experience. The plane was more comfortable, with a normal amount of leg room (vs the ridiculous reductions AA has made), more comfortable seats, screens to watch movies. It was a much better experience!

Awful. No counter attendants. No dinner offered due to delays.

Horrible service no Wi-Fi connection on both leg of the flight and they are refusing to fix bad service

3 hour delay…. Nearly 2 hours sitting on tarmac. Do better, United. Or at least have the sense to not say “we hope you enjoyed your flight with us” upon disembarking.

Flights were on time. Free Wifi on plane. Everything was well organized.

During landing. 2 crew members passed 3 times by my lane and didn't notice that people in front of us had their site to the furthermore reclined... That was uncomfortable and could have been dangerous.

The flight itself was excellent but the gate attendant made me check my carryon since she said it was an inch too big. I’ve had no problems with this carryon on recent flights on Qantas, Delta, Austrian, Southwest Airlines even though the overhead bins are the same size. there were other carryons in the bins that also looked larger than mine and there was room left in the bins for more. When I picked up my carryon from baggage claim one of the wheels had broken off.

The flight changed gates multiple times and flight had to be delayed multiple times

We called Kayak for a change due to the TSA situation in Atlanta. What we got was a canceled return flight (in error) and we had to find the mistake. Not happy with Kayak who blamed it on AA.

Tv screens and movie selection v good. Friendly staff. They were really worried about max capacity and room for carryons. That is never fun but i had no problem finding space when I boarded.

I was in last row so that is never great bc the person in front of me leaned his seat all the way back into me.

Delayed for mechanical and no updates on what was happening and how long the delay might be.

My flight from LGA was cancelled and my rebooked flight from JFK was delayed numerous times. I will now be getting home after 2am.

Flight was delayed half hour before boarding, but when I checked flight aware the plane that would Pick us up had a delay of more than an hour. AA should let us know in advance to avoid waiting several hours in the airport

On the return flight, arriving in Denver we sat on the tarmac in Denver for over 20 minutes.

Typical AA - late by 90+ mn. Gate changed twice... Changed the departure time 6 times No explanation, no communication on reasons for delay I travel with AA twice a year... and it is consistently very poor.. I will continue to use AA only when i have to.

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.

Extremely disappointing. My original Denver–Vancouver–Bangkok itinerary was cancelled due to a crewing issue. I was not proactively supported and had to drive back home after already reaching the airport. Communication was poor throughout, and attempts to contact customer service resulted in being on hold for nearly three hours without reaching anyone. Instead of being rebooked on the same direct routing the following day, I was rerouted onto a much longer itinerary via multiple cities and airlines, which resulted in arriving approximately 30 hours later than scheduled. At Denver airport, there was no visible Air Canada representative available to properly assist. Ground staff offered no real support beyond directing passengers to a phone number. There was no clear communication, no ownership, and no meaningful customer care during a major disruption. The final journey involved three flights instead of the original two, significantly increasing travel time and stress. Overall, the handling of the cancellation and lack of customer support was unacceptable. What could have been better? Clear communication during the cancellation Accessible customer service (phone support that actually answers) Proper in-person assistance at the airport Rebooking onto a comparable routing rather than a significantly longer one

Great setup on both flights except the last flight we got condensed dripping all over me in the last 20 mins of the flight

The last 3 hours it was freezing cold in row 56. Multiple people had their winter coats on and were utilizing the blankets provided by the airline. I also did not have easy access to figure out how to book my food allergy and advance for my meals. Most of everything I received was something I couldn't eat. This needs to be made more accessible. Also, I'm 5'10 which is the average height of the American male. I flew from Philadelphia to Toronto and then to Tokyo and the seats were absolutely unbearable. For that long of a flight it is impossible to get comfortable when doing anything. Flights need to have more space and stop prioritizing costs over people.

Again, we were rerouted all the way to Zurich and had a longer journey than expected.

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

I had a good comfortable seat. There was nearly an hour delay. There was an accident with the champagne, but I was well compensated. These things happen sometimes.

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

Information on your arrival and departure airports