$334 Find Cheap Flights from St. Louis to Portugal - Compare and Save

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 10/12. 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$779
Porto
Porto1 stop$893
Lajes
Lajes2 stops$2,239
Lisbon
Lisbon1 stop$779
Porto
Porto1 stop$893
Lajes
Lajes2 stops$2,239

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

Wed, Nov 4 - Tue, Nov 10
United Airlines Logo
6:30 am - 8:10 am
STL
-
LIS
19h 40m
1 stop
United Airlines Logo
11:20 am - 4:40 pm
LIS
-
STL
35h 20m
2 stops
$779United Airlines
Wed, Nov 4 - Tue, Nov 10
United Airlines Logo
11:45 am - 8:10 am
STL
-
LIS
14h 25m
1 stop
United Airlines Logo
11:20 am - 4:40 pm
LIS
-
STL
35h 20m
2 stops
$780United Airlines
Mon, Nov 16 - Wed, Nov 18
Air Canada Logo
9:23 am - 9:50 am
STL
-
LIS
18h 27m
2 stops
Air Canada Logo
11:20 am - 2:18 pm
LIS
-
STL
32h 58m
2 stops
$783Air Canada
Wed, Nov 4 - Tue, Nov 10
United Airlines Logo
9:23 am - 8:10 am
STL
-
LIS
16h 47m
2 stops
United Airlines Logo
11:20 am - 4:40 pm
LIS
-
STL
35h 20m
2 stops
$784United Airlines
Sat, Nov 14 - Tue, Nov 24
Multiple Airlines Logo
5:20 pm - 8:10 am
STL
-
LIS
32h 50m
1 stop
Multiple Airlines Logo
11:20 am - 10:27 am
LIS
-
STL
29h 07m
2 stops
$785Multiple Airlines
Sat, Nov 14 - Tue, Nov 24
Multiple Airlines Logo
5:20 pm - 8:10 am
STL
-
LIS
32h 50m
1 stop
Multiple Airlines Logo
11:20 am - 12:20 pm
LIS
-
STL
31h 00m
2 stops
$786Multiple Airlines
Wed, Nov 4 - Tue, Nov 10
United Airlines Logo
7:30 am - 8:10 am
STL
-
LIS
18h 40m
1 stop
United Airlines Logo
5:00 am - 10:54 pm
LIS
-
STL
23h 54m
2 stops
$787United Airlines
Wed, Nov 4 - Tue, Nov 10
KLM Logo
11:51 am - 8:00 am
STL
-
LIS
14h 09m
2 stops
KLM Logo
5:00 am - 4:50 pm
LIS
-
STL
17h 50m
2 stops
$793KLM
Sun, Jul 12 - Tue, Jul 28
Air Canada Logo
12:10 pm - 6:50 am
STL
-
OPO
12h 40m
1 stop
Air Canada Logo
12:15 pm - 6:42 pm
OPO
-
STL
12h 27m
1 stop
$893Air Canada
Mon, Jul 6 - Tue, Jul 21
Delta Logo
6:10 pm - 3:25 pm
STL
-
OPO
15h 15m
2 stops
Delta Logo
5:00 am - 10:15 pm
OPO
-
STL
23h 15m
2 stops
$943Delta
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 10 weeks before departure.

Good to know

Low seasonFebruary
Cheapest flight$334
Best time to beat the crowds with an average 40% drop in price.
Most popular time to fly with an average 18% 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 8397 reviews
8.5Crew
7.2Food
8.1Boarding
7.8Entertainment
7.8Comfort
Airline reviews

Only beverages were offered to first class and I thought the flight attendant could have also served the Delta Comfort as well instead of sitting down and staring at her phone and walking past all of us to the back of the plane to charge her phone more. There was a complete lack of turbulence and was safe enough for flights attendant to walk around in the front of the plane, collect trash and serve a few people water and turn off the seat belt light. Also didn’t enforce people putting their seats into the upright position and allowed two passengers to remain reclined during landing. They seemed out to lunch completely. Usually my experience on Delta is much better.

4.0 OkayMichelle, Jun 2026
ATL - PIT
Read more Delta reviews

Only beverages were offered to first class and I thought the flight attendant could have also served the Delta Comfort as well instead of sitting down and staring at her phone and walking past all of us to the back of the plane to charge her phone more. There was a complete lack of turbulence and was safe enough for flights attendant to walk around in the front of the plane, collect trash and serve a few people water and turn off the seat belt light. Also didn’t enforce people putting their seats into the upright position and allowed two passengers to remain reclined during landing. They seemed out to lunch completely. Usually my experience on Delta is much better.

Long story short, it was one of the better flight experiences I've had in some time when compared with other airlines.

Flight was great! This flight from Atlanta was even better than when I paid for Comfort from SNA to Atlanta.

Connection flights should be spaced out farther because too close I missed my connection.

Definitely a southern flavor. Cordiality was evident even though no drinks or snacks were served.

On time! There were plenty of airport employees who were able to keep us moving in the right direction. The crew on the plane were professional.

Left /arrived on time. Decent seat space. Like the wifi/plugs and entertainment. Windows and tray table were kinda gross. Attendants didn't start snack service til 40mins before landing. Two rows before us, captain came on to say there's turbulence and recalled staff to seats. So, no drink/snack. Later, attendants didn't stop to see if we had trash nor even look our way. Felt invisible! Almost all pilot announcements were not only unintelligible, but so quiet. We had no idea what she said.

Average seat comfort, a drink and chips were provided, early boarding because we checked a carryon at the gate was nice. Ticket pricing shenanigans, including fees to pick a seat, check a bag, and get food onboard - evidence the industry is reinvigorating last century’s strategies- destroys the experience before one ever arrives at the airport. It’s difficult to recognize any value or sustain loyalty in the end-to-end process making air travel more drudgery than pleasure.

Gate agent was unhelpful for handicapped boarding. Flight attendant seemed untrained.

No service flight that took 5 hrs and a stop at an unscheduled airport. Crew and pilots did their jobs

I paid for a confirmed upgraded aisle seat and was moved to a center seat in the back of the plane at the last minute.

Smooth travel. Immediate update prior flight delay so I can arrange myself properly without too rush.

Everything was the best it could be. Crew found me with pre- ordered food. Excellent experience!

Improve the food offerings and cabin seating. My wife would prefer to fly another airline, even with a connection for a more comfortable trip. A 737-8 should not be scheduled for a 6 hour segment, which turned into 7.5 hours due to the origin ground delay.

Packed flight, which makes it tough on crew and boarding staff (and the customers of course). But this was great boarding, clear instructions, etc. Traveling on the weekends are always fraught with danger as you have families and less frequent flyers thus more confusion. But this flight went as planned.

Destroyed my suitcase. Tired of talking about it. Cancelling my unite mileage plus account.

Read the fine print. This was my flight home. I booked my flight for the quickest way home. Had a carry-on and a personal item. Same as my outbound flight. Apparently I needed to pre-pay extra for my carry-on. When I checked in, I was told that I had to check it. I said I’ll pay for it, and was told that this wasn’t an option anymore. They said I still had to pay $50 to check my carry-on. I told them I’ll pay whatever to just carry it in as intended. I was not allowed, so eventually I paid $50 to check my carry-on under a plane that was half full, with overhead compartments that were even less full. My white carry-on suitcase was practically destroyed getting from Idaho falls to Denver to Orange County. The low price air fair was a bait and switch. Got me to the gate, made me pay extra, then didn’t even allow me to pay for a carry on. Not to mention that I paid the $8 for WiFi that didn’t work. All to get my suitcase destroyed. I don’t think I’m going to even keep my Untied mileage plus membership and card. Apparently, membership does not have its privileges for this one.

The flight was delayed, they didn’t even have water for the toilets or for drinks

Even through the flight was delayed due to storms near IAH The flight was great! The crew was so hospitable and professional

I flew from Santa Fe to Denver to catch a flight to London and the transfer of my luggage on arrival at Denver to the London flight worked perfectly. The crew on the ground and on board for the London flight were so friendly and efficient.

The flight attendants were extremely sourly and borderline rude. I did not feel appreciated as an AA customer once.

The flight back to Dallas was delayed, which has happened to me several times with American Airlines. There was no announcement, no update sent out, no compensation offered for the inconvenience.

It wa sort of on time; the cab was left with some trash

Our flight from JFK to Madrid was delayed. We had to go from one side of the Madrid airport (Terminal 4s to the far end of terminal 4 - Gate K98) to our gate in less than 30 minutes. Put passport control and security/baggage check and that’s very hard unless you’re Usain Bolt. I called Iberia Airlines and the telephone customer service told me that I was going to have to pay to re-book. Luckily the help desk in the airport (who was dealing with dozens of people from the same JFK-Madrid flight) did not charge us extra to reschedule to a flight 8 hours later. They also gave us a voucher for breakfast and lunch. Glad the actual person at the airport had some actual sense.

As always, most AA flights that we fly are almost ALWAYS delayed and that too multiple times. Very frustrating

Boarding was smooth and seamless and the flight was without incident.

For an long range economy flight I feel more space and more meal options need to be offered for flights over 5 hours

Our flight was repeatedly delayed for maintenance problems: scheduled for 9.30am, eventually delayed to 7pm! Very very inconvenient! AA should have provided a substitute plane much earlier.. On the other hand, Customer Service crew in Charlotte helped us to reach NY (LGA) by late afternoon. Thank you Patricia!! The actual flight was quick and very comfortable. As always a. excellent, professional crew. [no food on a a short hop).

Take-off delayed an hour because of a missing flight officer, so,arrived in Charlotte lates causing many passengers to miss connections. Otherwise a very good flight, safe and comfortable, with an excellent professional crew.

Little time between flight from Dallas to flight to Gainesville. We chose this one, 43 minutes between, because the price for a connection with at least an hour between, was so much higher. Had to ask passengers on the Dallas flight to please allow us to deplane ahead of them. The economy passengers allowed this. We had to walk very fast to the next gate, 35 gates away. Thankfully all in the same terminal. Getting to the small Gainesville plane was a little confusing as you enter an area that is boarding many small planes at the same time. We stood in the wrong line for about 15 seconds before realizing it was not our Gainesville flight. Since I had boarded at this gate in the past, I knew to check the signs carefully so we weren’t lost. The first class seat experience was wonderful. I really enjoyed the upgrade. We were offered an alcohol drink as soon as we sat down. I got something different but it was a great gesture especially since we really had to hurry to make the flight. We had packed expecting we might miss this connection, but made it. Our luggage didn’t miss the flight. American Airlines delivered our bags to our home the next day. That was very convenient!

It was a short flight so, everything went smoothly and we got to where we needed to be safely.

Didn’t make it on the flight. Delayed then had to be rebooked, which in turn had me waiting at the airport for another 8 hours before next flight

No TV on the flight. The charging outlet was not working. No food, even a sandwich. The served orange was poor quality.

Selected seats 5 months prior to date. Had email confirmation and seats were not honoured. Family did not sit together

Loved and was pleasantly surprised by the food!! Request Lufthansa to help transiting passengers at Munich (confusion whether to go thru passport control or not).

The flight was comfortable and the staff were helpful and friendly. However, we did not know we were flying PAL until we arrived in Canada, so it was a bit disconcerting. In addition, which port we were leaving from was confusing.

They did not let us board because one member needed a transit visa, which was not evident at the time of ticket purchase.

I was charge a baggage checking fee $68!! I volunteered to check my duffle bag which usually goes under my seat!

I did not like anything because the flight was cancelled yesterday and I did not get to arrive on time in Toronto as I was rebooked with another airline. This caused me to be really stressed out as I am an individual with back injury and to be forced to stay longer in an airport to accommodate a change of airline and the transfers associated with it Due to this I am probably not going to book through your website to eliminate this potentially chaos in the future

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

They messed up my seat so I didn’t get the one I paid for

Put me on standby; flight was late; missed my connecting flight; disaster

Flight attendants were fine, seats a bit hard but I use a cushion for extra support. The only issue was it was a bit too cool and I needed to ask for and received and extra blanket. I survived!!!

Very few things and/or people are excellent. It was very good.

Extremely uncomfortable seats. Experience was like a Frontier Airlines flight. Would not fly it again.

Very, very tight legroom. They must’ve jammed in an additional few rows of seat seating. Denver to Munich was the least legroom I’ve ever had on any flight, let alone a multi hour international journey. I will not take that flight again.

In my first flight with Air Canada we sat in the plane for 4:00pm to 6:30pm. Finally we were asked to get off the plane and we were told the flight was cancelled after 7:00pm There was o clear explanation of what was the problem. I was booked without my permission on a Delta Flight at 7:30pm that was leaving at 8:00pm and I still had to go get my luggage(my final destination was Rome with one stop in Toronto. The luggage claim for Canada was closed so had to return to finally get it on the luggage belt.. Of course I missed the Delta flight and all the next day flights were booked. I also lost what I paid for my stay in Rome because I did nt cancel in time. A complete nightmare.

Good food, overall very comfy. The flight was full so obviously not optimal, but it is what it is.

Perfect airline, super friendly, great service, tasty food. Would fly again.

Parents with permanently crying baby on board. Neither parents nor crew did anything to calm the baby. The food was extremely disappointing. Seafood stew was very, very small! Not even appetizer size! Seat had a gap in the back. Had to use a pillow to fill it.

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

Information on your arrival and departure airports