$342 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 3/20. 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$500
Porto
Porto2 stops$500
Lajes
Lajes2 stops$1,565
Lisbon
Lisbon2 stops$500
Porto
Porto2 stops$500
Lajes
Lajes2 stops$1,565

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

Mon, Apr 20 - Fri, May 1
United Airlines Logo
10:00 am - 10:30 am
STL
-
LIS
18h 30m
2 stops
United Airlines Logo
5:05 am - 10:59 pm
LIS
-
STL
23h 54m
2 stops
$500United Airlines
Sat, Apr 11 - Wed, Apr 22
Iberia Logo
8:02 pm - 11:45 am
STL
-
OPO
33h 43m
2 stops
Iberia Logo
8:20 am - 10:17 pm
OPO
-
STL
19h 57m
2 stops
$500Iberia
Wed, Apr 15 - Wed, Apr 22
Iberia Logo
12:25 pm - 11:45 am
STL
-
OPO
17h 20m
2 stops
Iberia Logo
8:20 am - 10:17 pm
OPO
-
STL
19h 57m
2 stops
$501Iberia
Tue, Mar 10 - Tue, Mar 17
Delta Logo
3:05 pm - 5:30 pm
STL
-
LIS
21h 25m
2 stops
Delta Logo
5:00 am - 8:42 pm
LIS
-
STL
20h 42m
2 stops
$503Delta
Sun, Apr 19 - Tue, Apr 28
British Airways Logo
6:11 pm - 11:05 pm
STL
-
LIS
22h 54m
2 stops
British Airways Logo
6:45 pm - 7:30 pm
LIS
-
STL
30h 45m
1 stop
$506British Airways
Mon, Apr 20 - Fri, May 8
Delta Logo
5:35 pm - 6:45 pm
STL
-
LIS
19h 10m
2 stops
Delta Logo
5:00 am - 11:59 pm
LIS
-
STL
24h 59m
2 stops
$507Delta
Tue, Apr 14 - Tue, Apr 21
Delta Logo
12:45 pm - 8:00 am
STL
-
LIS
13h 15m
1 stop
Delta Logo
10:00 am - 7:26 pm
LIS
-
STL
15h 26m
1 stop
$508Delta
Mon, Apr 20 - Sun, May 10
Finnair Logo
5:21 pm - 11:25 pm
STL
-
LIS
24h 04m
2 stops
Finnair Logo
6:35 am - 10:19 pm
LIS
-
STL
21h 44m
2 stops
$509Finnair
Thu, Feb 26 - Sun, Mar 1
Lufthansa Logo
11:39 am - 2:45 pm
STL
-
OPO
21h 06m
2 stops
Lufthansa Logo
6:00 am - 1:55 pm
OPO
-
STL
13h 55m
1 stop
$748Lufthansa
Wed, Mar 18 - Wed, Mar 25
Lufthansa Logo
11:28 am - 1:15 pm
STL
-
OPO
20h 47m
2 stops
Lufthansa Logo
12:35 pm - 11:51 pm
OPO
-
STL
16h 16m
1 stop
$821Lufthansa
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 January, when tickets cost $617 (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$342
Best time to beat the crowds with an average 40% drop in price.
Most popular time to fly with an average 15% 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 8193 reviews
8.5Crew
7.2Food
8.1Boarding
7.9Comfort
7.8Entertainment
Airline reviews

Excellent!!! Aeromexico is a great airline. What was not that good is the service provided by Kayak. It is never clear and not easy to manage.

10.0 ExcellentEdgar Otto Enrique, Feb 2026
BOS - MEX
Read more Delta reviews

Excellent!!! Aeromexico is a great airline. What was not that good is the service provided by Kayak. It is never clear and not easy to manage.

Flight delay was frustrating, also you cannot checkin online without delta app, web browser check-in throw errors

The gate agent was most helpful in getting me on to fly standby. I greatly appreciate it.

bulkhead seat had very little legroom - even in bsiness class.

The plane was an older model, so it wasn’t as comfortable as others. The flight attendants were not helpful during onboarding. It was a full flight so there was chaos finding space for baggage.

Sorry I didn't realize I was writing a review for each leg. Please see my previous review - it applies to the entire flight, not just a single leg.

This is the first time I've been disappointed with Delta. I was called by Delta to see if I would volunteer to change flights since my original flight home was overbooked. I accepted. The modified booking only provided me a 35 minute layover - when you subtract the fact that boarding closes for a flight 15 minutes early, that gave me 20 minutes to run for one end of the airport to the other. I barely made it. On the 2.5 hour flight to Tampa, the crew repeatedly let us know over the intercom that they cannot serve drinks or snacks due to safety/turbulence. I would have accepted this reason if they did not CONTINUALLY SERVE DRINKS AND COOKED FOOD to First class. If safety is the excuse then the entire plane should be strapped in for safety. On top of this the air conditioning vents were not working correctly and the plane was uncomfortably warm. I love Delta and am a loyal Delta traveler, and I have never had an experience like this. I don't know if there's a disconnect between availability among third-party sites like KAYAK and the airlines or what, but when overbooking causes issues like this for travelers it should be reviewed and changes to the booking process should be made. I blame BOTH KAYAK and Delta for this terrible experience.

boarded at 5:30 pm, pushed away from gate at 6pm ... takeoff was not until ~6:45pm; disappointing

Smooth boarding, pleasant and professional lady checking us in. Crew service was excellent, again pleasant, but professional. Nice touch-down on landing! Thank you Delta. 💗

Originally, I was booked in economy. I paid several hundred additional dollars to upgrade to first class. Then I paid several more hundred dollars to change my flight to a slightly earlier flight. I asked if the changed flight would also seat me in first class, and I was told that it would. When I boarded the plane, however, I was seated in economy. So, I paid $500-600 more than I paid for my original ticket for an upgrade and a changed flight - received the changed flight (which was nice), but did not receive the upgrade. So, I was not completely satisfied.

Very disappointing given gate agent behavior. Filed a formal complaint with United.

Do not like the size of the overhead bin. I think staff should monitor the size of suitcases that are being carried on by passengers to ensure they meet the size requirement.

Crew was great (professional, attentive, prompt). Snacks for 4 hrs flight is deplorable.

Flight delayed. WiFi connectivity very poor if not existant. Last minute arrival forced me to run to catch my connection.

Both of my flights arrived early and check in process was smooth

Terrible. No customer service, no food, no drinks on a 6 hour premier economy booking.

Short flight, but no drink/snack service. The flights both going and coming were delayed.

Much better than Spirit. I was please by the easy fast check in and boarding

Check-in and in-flight staff were better than average. The seat was a fair size but too hard and not enough padding. The cushion/pillow provided is poor (thin and seems to be disposable ,it provides no effective cushioning or support). Food was OK-ish but no choice of inflight snacks and no easy place to get drinks other than water (I could ask for juice by intruding into the staff area at the back of the plane) Entertainment was very good actually. Overall better than I expected from a US-based airline (sorry!) but compared to ANA or Singapore it was so-so. (I live in Japan so they are my comparative airlines)

Everything was on time Will use united again for sure

The flight was fine, once we got underway. It was more than hour delayed

Beverage service was not good. Also just one service in 5 hr 30 min flight. No ask fir water ir anything beside one time beverage service.

Waited for oxygen tanks for 30 minutes after boarding was complete.

The seats are too uncomfortable for anyone over 5ft 8in. I'm 5'10" with a back and hip issue and I was in pai for the full duration of the flight.

The flight was on time/early, attentive crew, and everything overall went smoothly. Disappointed that WIFI was not working for the flight.

One day, I do so hope for a gluten free snack! Seems like with the rest of the world FINALLY figuring out what gluten free is, American Airlines would too. Fingers crossed!!

The flight was significantly delayed for 6.5 hours because of snow. There was no communication once the plane returned to the gate regarding when the flight would resume. Other flights were departing while our flight was being unloaded for reasons unknown. Our flight also seemed out of the queue regarding further deicing, refueling, and waiting to Taxi to the runway.

Flight was on time and the meal and service were good.

The accessible bathroom should be visible to people in Economy class.

Flight was delayed for 2 hours, then last minute the change to on time. The satélite location is far and a nightmare to get to.

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.

Was delayed at every point/ connection. Luggages missing for 5days. Had no medications for diabetes and high B/p. when bags where finally delivered on the 30th, the insulin and ozempic were no longer patent, as the ice pack had since dissolved and the authenticity of the med is now questionable, since they must be refrigerated. Please have them refund my bag fees. I should sue them for all the inconveniences caused to me.

The plane was delayed substantially due to a mechanical problem, that being said, the airline was very fair with providing a meal coupon for us. I would rather arrive late on a mechanically sound plane than the alternative. The food served in the plane was just awful, however and I recommend a new catering company.

I waiting for 2 hrs to retrieve my luggage. Didn't get home till 3am.

The flight left late and I didn’t get a glass of bubbly upon boarding (which I’m used to when booking business class on other flights), but otherwise it was a pleasant flight with lovely, helpful crew members and I enjoyed my meal.

Flight cancellations, delays, mass confusion and disorganization! That’s Air Canada for you, nothing new. I would have chosen a different airline if it were an option, and Air Canada continues to prove they don’t care about their customers.

everything was fine. but paying for 1 piece of check-in luggage and denying passengers to board with carry-on luggage which by air line's standards does not fit is not acceptable. when one travels for a longer time one needs to have some essentials

Couldn't fit knees, only 1 toilet working, didn't get anything to drink cause the stewards were not able to get to us

Flight was canceled for a reason they knew hours before but did not mention. Next the gate chnage from 37 to 38 at least 10 times. Ridiculous.

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.

Service and food were excellent. Incredibly friendly and competent staff. Flight was delayed over and hour and I had to run between terminals to get my connecting flight.

Missed it by a couple minutes and couldn’t find an alternative flight so had to spend the night in DC and after much shuffling from 1 airline to another managed to get a United to Frankfurt.

There were only 2 toilets and one of them did not work in business class. We are not allowed to cross classes so had to wait in line to use the toilets!! The entertainment touch display was finicky and did not work all the time.

We missed our flight. There was not enough time built into the layover to get through immigration, customs, bagclaim, bag rechecking, and the long trip to another terminal and gate. Kayak really screwed up. We took the bus up to Wisconsin and then were picked up in Brookfield by private car. It was lucky we didnt miss the last bus out.

I tried both on line and by calling the Customer Service line to arrange for a special meal as i have food intolerances. I was under the impression from your service representative that I was successful. I was not. I cannot eat spicy foods and get very ill if i eat bell peppers. I could not eat either menu choice and no special meal was actually ordered. ( your representative tried to order it for a flight that did not have meal service!!! - found this out later). Your wonderful cabin crew managed to put together a fruit, salad, roll and cheese tray for me so I had something to eat. WHY WOULD YOU SERVE SPICY FOOD, WITH NO MILDER OPTION,ON AN INTERNATIONAL FLIGHT???

Crew was professional and great, flight was clean. However food was pathetic. I ordered a Hindu meal assuming no meat but they served chicken. Need to be very specific- Hindu meal should be categorize as Vegetarian - no meat or egg. Or it should be specific that we are serving meat.

Late flight Delays Poor service Poor staff Worst airline ever

Ground staff and cabin crew were excellent. Flight was perfectly on time. Zero issues.

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

Information on your arrival and departure airports