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$487+ Cheap flights from St. Louis (STL) to Porto (OPO)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 1/7. Fares are subject to change and may not be available on all flights or dates of travel.
STL — OPO
Nov 26 — Dec 31
Tue 11/26
Tue 12/3
1 adult, Economy
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1. Tell us where you want to go
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Cheap flight deals from St. Louis to Porto

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Porto (OPO). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated November 21, 2024.

Most accurate provider

AranGrant
3 stars

Most trusted provider

AranGrant
3 stars

Popular in

June

Cheapest in

November

Round-trip from

$955
(United)

One-way from

$487
(Kiwi.com)
Provider with most accurate pricing for Lambert-St Louis-Porto flight deals.
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Provider most trusted by Cheapflights users for Lambert-St Louis-Porto flights.
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High demand for flights, 38% potential price rise
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Best time to find cheap flights, 43% potential price drop
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From Lambert-St Louis to Porto
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One-way flight from Lambert-St Louis to Porto
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Find flight deals from St. Louis to Porto

Best flights from St. Louis to Porto
Discover carefully curated flight deals from St. Louis to Porto that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated November 21, 2024.

This United deal was found by Cheapflights users on 11/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/237:30 amSTL - OPO
1 stop20h 15mMultiple Airlines
Wed 5/76:00 amOPO - STL
1 stop13h 30mMultiple Airlines
Deal found 11/19$955
This United Airlines deal was found by Cheapflights users on 11/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/238:50 amSTL - OPO
2 stops18h 55mUnited Airlines
Wed 5/76:00 amOPO - STL
1 stop13h 30mUnited Airlines
Deal found 11/19$959
This Gurufare deal was found by Cheapflights users on 11/19. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Gurufare is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 4/241:27 pmSTL - OPO
2 stops15h 53mLufthansa
Wed 5/76:00 amOPO - STL
1 stop13h 30mLufthansa
Deal found 11/19$1,027

Find flights from St. Louis to Porto within your budget

Customize your flight search to find flights from St. Louis to Porto that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,629,791 searches. Data last updated November 21, 2024.

Fly from

Any airport

Fly to

Any airport

Route

Depart

Return

Price

St. LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Wed 4/23

7:30 am-9:45 am

1 stop20h 15m

Porto

Wed 5/7

6:00 am-1:30 pm

1 stop13h 30m

$955

St. LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Wed 4/23

8:50 am-9:45 am

2 stops18h 55m

Porto

Wed 5/7

6:00 am-1:30 pm

1 stop13h 30m

$959

St. LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Thu 4/24

1:27 pm-11:20 am

2 stops15h 53m

Porto

Wed 5/7

6:00 am-1:30 pm

1 stop13h 30m

$1,027

St. LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Tue 1/7

5:05 pm-7:05 am

2 stops32h 00m

$487

Flights are sorted by cheapest round-trip flights first.

Deals found on 11/20

Compare providers for flights from St. Louis to Porto

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Porto in November.
ProviderPrice AccuracyTrust Score*
AranGrantPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on St. Louis-Porto flights, users find the pricing of AranGrant to be most consistent on Cheapflights vs. AranGrant Users can find the same prices on St. Louis-Porto flight deals on Cheapflights vs. AranGrant >95% of the time. Price accuracy is based on data collected from St. Louis-Porto flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-Porto flights, Cheapflights users trust AranGrant the most. AranGrant has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-Porto flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from St. Louis to Porto

Have a flexible travel schedule? Discover the best time to fly to Porto from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Travel insights for flights from St. Louis to Porto

Get recent, data-driven insights about flights from St. Louis to Porto including ideal travel times, pricing trends, and more.

What is the cheapest month to book a flight from St. Louis to Porto?

Currently, January is the cheapest month in which you can book a flight from St. Louis to Porto (average of $517). Flying from St. Louis to Porto in June is currently the most expensive (average of $993). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from STL to OPO?

Find hourly flight availability from St. Louis to Porto. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated November 21, 2024.

Unlike in the afternoon, when flights are generally more expensive, you can save up to 35% on flights from St. Louis to Porto by exploring options for tickets at noon.

Rainfall in Porto by month

Plan your trip to Porto by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in Porto ranges from 0.7 - 7.7 inches per month. December is typically the wettest month, when rainfall can reach 7.7 in. July is typically the driest time to visit Porto when rainfall is around 0.7 in.

Temperature in Porto by month

Plan your trip to Porto by taking into account the average temperature totals by month.

If weather is an important factor for your trip to Porto, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 68.0 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 48.2 F).

Reviews of airlines servicing Porto

Get insights into the airlines that provide service to Porto. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Porto. Reviews last updated November 21, 2024.
United Airlines
7.4
Good
9,173 reviews

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.7

Boarding

7.7

Reviews

1 / 10

Good boarding process. (Nice to be able to buy Group 2 boarding option.) Plane was clean. Tried to avoid full flight by flying on Saturday, but plane was full anyway. Gate area in Houston should have charging options. Should be a lounge for people with American Express Platinum Card in Houston Airport.

United Airlines
7.4
Good
9,173 reviews
United Airlines
7.4
Good
9,173 reviews

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.7

Boarding

7.7

Reviews

1 / 10

Good boarding process. (Nice to be able to buy Group 2 boarding option.) Plane was clean. Tried to avoid full flight by flying on Saturday, but plane was full anyway. Gate area in Houston should have charging options. Should be a lounge for people with American Express Platinum Card in Houston Airport.

Lufthansa
6.8
Okay
7,150 reviews
United Airlines
7.4
Good
9,173 reviews

Entertainment

7.1

Comfort

7.3

Crew

8.1

Overall

7.4

Food

6.7

Boarding

7.7

Reviews

1 / 10

Good boarding process. (Nice to be able to buy Group 2 boarding option.) Plane was clean. Tried to avoid full flight by flying on Saturday, but plane was full anyway. Gate area in Houston should have charging options. Should be a lounge for people with American Express Platinum Card in Houston Airport.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Porto. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What are the cheapest airlines flying from St. Louis to Porto round-trip?

    United Airlines, at $959, was found to be the cheapest airline from St. Louis to Porto. An alternate airline flying to your destination would be Lufthansa. Users have found that United Airlines is 2% cheaper than the other options available to this destination.

  • Can I find deals for flights from St. Louis to Porto that include hotel bookings?

    Yes. In addition to deals on St. Louis to Porto flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Porto?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Porto.

  • Can I find deals for business class flights from St. Louis to Porto?

    Yes. Cheapflights offers flight deals from St. Louis to Porto by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from St. Louis to Porto?

    Currently, January is the cheapest month in which you can book a flight from St. Louis to Porto (average of $517). Flying from St. Louis to Porto in June is currently the most expensive (average of $993). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

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Top airline flying from St. Louis to Porto

Discover the top airline that operate flights from St. Louis to Porto. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,629,791 searches. Data last updated November 21, 2024.
AirlineCheapestAverageFlexibilityOn-time
United AirlinesCheapest$752Average$1,226FlexibilityNo cancel feeOn-time69%
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