$362 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 1/12. 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.
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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 5 days
Lisbon
Lisbon1 stop$705
Porto
Porto1 stop$745
Lajes
Lajes2 stops$2,714
Lisbon
Lisbon1 stop$705
Porto
Porto1 stop$745
Lajes
Lajes2 stops$2,714
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 February, when tickets cost $520 (return) on average. On the other hand, the most expensive months are December and September, when the average cost of round-trip tickets is $1,776 and $1,304 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 season

February

Cheapest flight

$362
Best time to beat the crowds with an average 35% drop in price.
Most popular time to fly with an average 8% 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.
7.4
United AirlinesOverall score based on 10106 reviews
6.7Food
7.1Entertainment
7.7Boarding
8.1Crew
7.3Comfort
Airline reviews

The flight to America was freezing. The overnight flight back to the UK was boiling hot and the cabin stank of toilet or occasionally perfume, even though I was several rows back from either bathroom. Food was tiny portions. Two small pieces of tough and dry beef in random gravy with pretend mashed potato raking up most of it. Very little veg. Salad was ok. Wooden cutlery broke within minutes of using. Lots of old films for entertainment. Some new ones. Generally a bit rubbish.

2.0 MediocreK, Aug 2026
Read more United Airlines reviews

The flight to America was freezing. The overnight flight back to the UK was boiling hot and the cabin stank of toilet or occasionally perfume, even though I was several rows back from either bathroom. Food was tiny portions. Two small pieces of tough and dry beef in random gravy with pretend mashed potato raking up most of it. Very little veg. Salad was ok. Wooden cutlery broke within minutes of using. Lots of old films for entertainment. Some new ones. Generally a bit rubbish.

I almost missed my connection in Chicago due to having to wait on a gate to be open I am assuming. Having to run from E terminal to C terminal and I barely made it there before they closed the door. This may not be the actual airline's fault it's crazy how there is so little time between flight especially when they are placed so far apart in the airport.

Our flight was great with an unexpected upgrade. However, four days into our travel we are still without a piece of luggage. The bag tracker has not been accurate, the airline is not communicating with me or the luggage delivery service and no one is willing to take responsibility or guarantee any kind of support or reimbursement. Unfortunately, we do not have the option to easily shop to replace items as we are currently on a cruise. I have been very disappointed by United Airlines response.

Fine not above and beyond as I had a connection that was delayed due to maintenance

HORRIBLE, my initial flight was cancelled, they made me pay $200 extra dollars and that got cancelled as well! After 6 cancellations I decided to get a refund because I needed to get home to my babies. Out of $1000+ dollars they offered me only $40 in refund! Totally unacceptable! The flight that they cancelled I was able to fly it on another airline. I had to spend $400 on one way tickets just to get home! I’m still getting the runaround.

Flight was delayed. De-icing took a while. When we landed had to wait for another plane to vacate our gate. Just an overall bad experience.

Flight was delayed only slightly before takeoff due to traffic control. However, the flight arrived early to ORD. Good flight. United has been very reliable for me.

Overall a very poor experience - booked premium economy tickets but due to last minute flight delays , all my itinery went for a toss and had to fly economy class with no access to lounge or any compensation by united airlines to make up for the flight delays . i had expected better experience than that from united.

Onboarding - it would be great to see on the screen what group they were boarding. It was very confusing on who was boarding (even though they called it out) they were not clear and the space to board was strange.

Older plane. Food was really bad, almost not worth the effort. Huge difference with European based airlines.

My luggage was not sent with us. Not sure if this is Envoy Air responsibility but that was a very BAD experience

American delayed the flight for a crew rest period. The delay occurred late in the evening - the earliest i can find is 10:20 pm. With a 6 am flight anyone on the flight would have already have been asleep (unless you are insane, a vampire or on drugs) and at least for me i was already on the way to the airport at 445 am the next morning when i discovered they delayed the flight until 9 am. Given the incoming flight was in the air at 6 pm the evening before this should have been figured out a lot more timely that was there only crew to use. Just frustrating given there is no consideration for customer experience anymore in flying.

Good crew and flight was on time. It’s a small plane with limited overhead luggage space. They said the overhead space was full and I had to check my bag. There was still space when I got on. Waiting for my checked luggage added 30 minutes to my trip. Not the end of the world but also not great.

Trip delayed for 2 hours because of rain. We boarded and have to get down the flight and reboard again.

No enough space plus only allowing one laggage instead of two like other airlines.

Qatar airways ,boarding arrangements at Hamid international airport could been better

Two flight changes before the scheduled flight. On the day of the flight, the flight was delayed, which caused the connecting flight to be missed. Then, I was directed to another airport (CUN) and traveled to Tulum. American gave a $12 voucher for lunch. The least expensive item on the menu at a Mexican restaurant was $9.99. Driving to Tulum was a bad auto crash, and traffic was delayed two-plus hours. The bottom line is that we should have been at the hotel at noon, but it ended up at 11:30 PM.

Miami lounges were overcrowded and we were unable to get in. We only had a short time. But the banks are too tight in all American hubs

Overall boarding and debarking is a joke. I dont even bring luggage anymore on trips because you can never allow them to be place then in the overhead bin or you have to pay or you check them which is even worse having to wait for your luggage on the tarmac.

First time flying internationally with AA and probably my last. Not military friendly at all. Didn't allow free checked bag for military family members (dependents) on orders like other airlines. We were charged $100 for baggage weight overage (5 lbs!)even though we had military orders allowing us extra.. Didn’t allow military members to board early. Inefficient and long wait time to board. Seats are smaller and more uncomfortable than other airlines.. no drink service for over 7 hrs of flight! After initial meal was served, the crew never offered a snack or drinks until the breakfast's was served 1 1/2 hrs before landing. Overall expensive and poor experience for the entire flight.

Boarded on time and arrived early. Overall quick flight. Snack and beverage offered.

Boarding and times were all good. Food was as expected and enough. Comfort for a 6’ tall male 200 lbs (somewhat average sized) was terrible. It was just SO much more money to upgrade to premium economy. It’s a 777 so seating is 3-4-3 and is really crammed. What are you going to do? The only real downside is not being able to sleep so your first day in Europe is a write off. I suppose if you need that first day then pay the extra $500 to get premium economy and maybe you can sleep and wake up with some energy?

Good but I don’t received my bags yet is been 5days still no update

Flight cancelled. Major disruption to our travel. Do not use Air Canada from KC. To few flights.

Friendlier staff who are nice to the elderly who need assistance

Service was great. Flight was delayed an hour which made our connection very tight and stressful. But we fortunately made it.

There was a mistake with the first name we only discovered at security. Air canada was unable to correct it to match then passport since it was booked through an agency. The agency could not correct it either since they need at least two hours to do that. We could not fly and lost a bunch of money. Learned my lesson about kayak.

Fresh fuit or veg snacks would be so great, but there are two good restaurants in Denver airport. Try Etais UDIS or Freshens DIA for nutritious delicious pita sandwiches/ donairs and crepes in Freshens.

I appreciate the fact that the flight took off and landed on time What I didn’t like they never offer a snack eg nuts/cookies/chips

Air Canada seems to be understaffed which caused delays at every point of the flight—delays at departure, delays in the air (circling), delay after landing, delays at the gate before disembarking. Horrible experience. And my son, who departed Toronto today, experienced delays because the passport scanning system was down and was told that he would not be able to board his flight. Toronto airport is a mess!!!!

Very bad 3 times change the gate and too much delay...

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

Before the flight I received an email from LH that our seat were changed to other comparable seats. At boarding however we found our reassigned “comparable” seats were directly by the toilet. They sure were no “comparable “ seats and we were quite disappointed!

Poor communication from airline, didn't start boarding until 15 minutes after we were supposed to be in the air and there was no communication from anyone about a delay except the screens showing we were "on-time" and already "boarding" which finally updated 5 minutes after we were supposed to be in the air to "delayed".

The flight was delayed more than 1.5 hours. Phone calls to united did not satisfy our need to get to Chicago to met family for fight to europe. I was told the flight was booked thru luftansa and united could not make adjustments. When call luftansa they were unaware of the significant delay on the united flight out of mci. They would not authorize a flight change. We went to the airport, as if we would be flying as scheduled, United checked us in, as if our flight would leave as scheduled. We took our bag to be checked to the baggage drop and the agent their confirmed our flight was significantly delayed. She worked for 30 min to get us on another flight. We ended up flying to Denver then to Munich. The rest of the family that flew to Chicago for our meet up and flight to Europe ended up flying to Munich alone. We meet up in Munich for our last leg to luxembourg. In luxembourg we learned on bag was scheduled on our delayed flight. The flight was canceled and we did not receive the bag in lux. We filed a lost back claim. Now 3 days later we STILL do not have the bag. It is apparently in luxembourg and they maybe tried to deliver, however the names on the door of the air b&b do not match the name on the baggage claim so the French speaking delivery person called no one could understand him so he took the bag and left. My brother, traveling with me under a different reservation , has been without essentials for 3 days. One or all of us has stayed "home" each day waiting on the bag. Today was my turn. Delivery window was 10:30 to 2:30. No attempt to knock or ring bell. After the hang up call, my brother called me and told me to check the door. There was nothing there. No sign of attempted delivery, no delivery man, nothing. Being unable to change clothes and having family members take turns waiting on a bag that never comes has ruined this family vacation. Thanks United/Luftansa

The flight left an hour late and no explanation. Food was basically a few snacks out of bags and tiny cup of soda. Crew was pretty friendly.

The The check in process was terrible on both ends. It was not clear if we should use the United, Lufthansa, or Aragrant number. It took over an hour to check in on the front end – and then at return the Lufthansa online check in failed multiple times and only after two calls to their phone number could we accomplish the task. The link to the Kayak site provided no access for check in. This difficulty and ambiguity on both ends will affect our interest in using Kayak for foreign travel in the future.

You lost my bag then waiting on the phone for 30 mins for customer service just to be directed to call another number

Boarding staff, crew and food needs a lot of improvement!! It was awful Aircraft was old with minimal legspace

Plane was very delayed. US agents unhelpful in connection flt and in seating. No real info given on delay.

It was not British Air, we were put onto Air Portugal for our London to Lisbon leg.

Horrible leg room - coach seating with empty seat in middle on a 3 across seating. You buy business class for comfort which includes leg room. Absolutely no entertainment options either. Awful experience

The on flight entertainment system touch screen system and the USB charger did not work on multiple seats on least 4 seats an in different rows. The attendant tried to reset the system but was un successful. I couldn't change my phone to get my ticket for my next flight. This was an international flight I changed seats and the problem was the same. the flight attendant offered his power bank

Business class was nothing more than Economy with middle seat empty. Uncomfortable seat and leg room. A mom behind me had a 18 month/2 yr old on her lap, who had his feet on my back all the time- while middle seat remained empty. Pretty much not worth the fare. Very disappointed.

Once again I purchase a business class ticket and the seat is exactly the same as cattle class, the only difference being is that BA install a janky table over the middle seat so there is somewhere to place your complimentary drink, the tray table is just big enough for the small tray, so if you are not concerned about getting fed and watered on the plane or getting access to the BA lounge I would save your money and fly cattle, PS the cabin crew were exceptional in every way, shame about the equipment

Our flight from ORD was cancelled and BA rebooked is on a flight that originated before the time that they booked us on it. They did not realize we were already arrived in Chicago. Then American Airlines helped us get checked in to the new flight (the one BA assigned to us) which flight we did take although it was delayed about 2 hours, and our assigned seats that we paid for - on the original flight- were lost we did at least get to sit together. It was not too painful for all the changes and we made it to the UK alright though all in all with all the delays and cancellations the flight took about 20 hours to get us here.

though there was space in the cabin they asked us to check in our trolleys. As a result lots of things arrived damaged in Larnaca. They were fragile. When we asked the attendants why that.....they said talk to the captain!!! Unbelievable!

When bussing people to/from the gate, don't pack everyone in like a can of sardines and don't send the bus on its way if the plane isn't ready. Waited for about 40 minutes packed in this bus...both ways!

Boarding ,checking in was easy and quick . Comfort was not good.

A Perfect 2.5 hr flight. No amenities, but we did not expect any.

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

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