$387 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 8/15. 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$666
Porto
Porto2 stops$812
Lajes
Lajes2 stops$1,487
Lisbon
Lisbon2 stops$666
Porto
Porto2 stops$812
Lajes
Lajes2 stops$1,487

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 - Mon, Apr 27
American Airlines Logo
8:03 pm - 5:55 pm
STL
-
LIS
15h 52m
2 stops
American Airlines Logo
8:25 am - 7:33 pm
LIS
-
STL
17h 08m
2 stops
$666American Airlines
Mon, Apr 20 - Mon, Apr 27
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
$669American Airlines
Tue, Apr 21 - Wed, Apr 29
KLM Logo
12:23 pm - 10:55 am
STL
-
LIS
16h 32m
2 stops
KLM Logo
5:00 am - 4:42 pm
LIS
-
STL
17h 42m
2 stops
$674KLM
Tue, Apr 21 - Wed, Apr 29
British Airways Logo
12:59 pm - 9:05 am
STL
-
LIS
14h 06m
1 stop
British Airways Logo
7:20 am - 7:30 pm
LIS
-
STL
18h 10m
1 stop
$681British Airways
Tue, Apr 21 - Wed, Apr 29
Multiple Airlines Logo
2:33 pm - 11:50 am
STL
-
LIS
15h 17m
2 stops
Multiple Airlines Logo
7:20 am - 7:30 pm
LIS
-
STL
18h 10m
1 stop
$694Multiple Airlines
Sun, Apr 19 - Sun, Apr 26
Delta Logo
5:59 pm - 6:45 pm
STL
-
LIS
18h 46m
2 stops
Delta Logo
5:00 am - 11:13 pm
LIS
-
STL
24h 13m
2 stops
$725Delta
Sun, May 3 - Sun, May 10
Delta Logo
7:25 am - 8:50 am
STL
-
LIS
19h 25m
2 stops
Delta Logo
5:35 am - 4:55 pm
LIS
-
STL
17h 20m
2 stops
$727Delta
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 - 11:50 pm
OPO
-
STL
39h 25m
2 stops
$842United Airlines
Fri, Aug 7 - Wed, Aug 19
Air Canada Logo
2:40 pm - 7:00 am
STL
-
OPO
34h 20m
2 stops
Air Canada Logo
2:25 pm - 6:42 pm
OPO
-
STL
34h 17m
1 stop
$859Air Canada
Tue, May 5 - Tue, May 12
Air Canada Logo
1:05 pm - 12:50 pm
STL
-
TER
18h 45m
2 stops
Air Canada Logo
1:40 pm - 12:06 pm
TER
-
STL
51h 26m
2 stops
$1,570Air 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 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$387
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 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 8319 reviews
7.9Comfort
7.8Entertainment
8.1Boarding
8.5Crew
7.2Food
Airline reviews

Kayak botched up the booking, i had to call delta and fix. In the process Delta failed to honor my comfort plus seat assignment that i had previously.

2.0 MediocreSreekumar, Mar 2026
FLL - DTW
Read more Delta reviews

Kayak botched up the booking, i had to call delta and fix. In the process Delta failed to honor my comfort plus seat assignment that i had previously.

Entertainment is ok! Boarding and seat with zone is terrible. I paid for the seats but you didn’t give me what I paid for which is exit isles.

the crew cancel the morning service due to the weather. Then the flight got deverted to Nashville . we were on the ground for over two hours the only gave us water once... no food or any snacks.... the crew should have handled better and offered something to passengers.

My recent experience was excellent on Delta! I flew with Delta Comfort and I was really comfortable in my seat. I enjoyed the in-flight service. The flight attendants were so friendly and hospitable. I love the snack on the flight as well. This was my first time flying on Delta and I will definitely consider flying with them again.

My flight was cencaled due with the bad weather on Sunday the crew was poorly mistaken my luggage supposed depart with my flight instead I didn’t have my luggage for almost 3 days the website is poorly respond to my complain until I have someone to do it my connection smooth their not even respon or email me even the have my luggage

Delta needs to step its game up get a more reliable internet service. Internet service was non-existent for this flight.

Mechanical Delay of over an hour with multiple gate changes. Entertainment system down for rejuvenation.

This was a Latam operated flight. Seats seemed a bit narrow in business class. Older aircraft.

I had a flight cancel and had it rerouted. When the rerouted they put me at a window seat instead of an isle. It was hard sitting by the window because the couple with masks on were making out. I get motion sickness which is why I need to have the isle seat.

NEVER MADE THE FLIGHT BECAUSE DELTA SAID THEY CAN NOT

I will never fly ANA again. They lost one of my large pieces of checked luggage, the heaviest one with the most valuable items in it, and they said they will not send me an email unless they can't find it, even though the paper they gave me to track the status of my lost luggage requires a code from an email they are supposed to send me so I can do baggage tracing. They claim to be an international airline, but they also insist on calling a Japanese telephone number to confirm where to send the lost baggage if they find it. It is impossible to find an actual contact email address for customer support on their website, and their AI chatbot is unhelpful, directing you to a webpage that says it is for contact information but does not have any actual email addresses or phone numbers listed on it. My seat in economy did not recline at all, even though I was not sitting in an exit row nor the very back row. I had to sit in the fully upright position for over ten hours of international travel. Awful experience overall.

No seat back entertainment. And app had a hard time getting entertainment loaded.

ticket agent lady wás very helpful , she arranged wheel chair for my elderly mother

Didn't make the flight because the first leg of my flight was canceled and the next leg was already booked.

My flight was canceled a few hours before boarding. I was rebooked on Copa airlines and missed an important meeting .

Good quick flight on a small but comfortable plane. I'm 6'3 and had plenty of space.

Experience was great - no complaints. Took off on time, landed early. Got to the gate relatively quickly - took a little bit of extra time to deplane but nothing excessive.

Business class seats felt very cramped compared to other airlines.

Economy plus was so cramped I could not use my laptop. It was beyond bad.

OK, we were delayed and had to de plane and reboard.

A first class seat should fit a fat person, and this doesn't. The trays in the armrest are less functional than an ordinary tray in the back of the seat.

The flight attendant was friendly and efficient. The temperature was kept nice and cool. The plane was nice, but filthy. There were visible spills on my tray table. The gate agent was somewhat rude with her announcements and in speaking with other customers.

I appreciate that I finally got the seat I paid extra for this time. Thank you

I would have liked a pillow. The vegetarian wrap and oaten cake was good.

I would have liked vegetarian and gluten free options for evening dinner time flight. I would have like a pillow on the international overnight flight . The veg wrap and oaten desert on the international flight was good

The experience at checkin for my American Airlines flight from Sacramento to LAX was very good including the assistance I received in getting my bags checked in and boarding passes printed. Was pleasantly surprised the my bags were checked through all the way to my destination at Clark International Airport in Angeles, Philippines.

Absolutely terrible. Would never fly American again. 2 deplaned incidents and delayed by close to 24 hours. $12 meal voucher for first class passengers was an insult to the injury. Pathetic.

Terrible planning. And even worse gate agents. Absolutely rude behavior.

Half of the TSA checkpoints at PHL are closed. Also, there is no standby for first class passengers. You can only standby for coach. Very dated policy and inconsistent with peers.

Flight was scheduled at 11:26am but they keep Delaying until midnight. They waited at airport restless.

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.

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.

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