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Cheap flights from St. Louis (STL) to Porto (OPO) from $524

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/3. 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.
STL — OPO
Jun 16 — Jun 231
From?
To?
Sun 6/16
Sun 6/23
1 adult, Economy
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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 June 11, 2024.

Popular in

June

Cheapest in

February

Average price

$1,619

Round-trip from

$524
High demand for flights, 33% potential price rise
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Best time to find cheap flights, 42% potential price drop
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Average for round-trip flights in June 2024
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From Lambert-St Louis to Porto
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What is the cheapest day to fly round-trip from St. Louis to Porto?

Users have found that leaving on a Monday can be a cost-effective option. It’s possible to save up to 47% on your flight compared to booking on days when demand is much higher.

What is the cheapest month to fly from St. Louis to Porto?

Flights from St. Louis to Porto lean towards being more expensive in June. Prices are generally better when you fly from St. Louis to Porto in February, with the cheapest ticket starting at $615.

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

Unlike in the afternoon, when flights are generally more expensive, you can save up to 25% on flights from St. Louis to Porto by exploring options for tickets at noon.

Cheap St. Louis to Porto flights in June & July 2024

Find cheap flight options from St. Louis to Porto specifically for the months of June and July 2024. Explore affordable fares based on user searches. Over the last 7 days, Cheapflights users made 3,020,828 searches. Prices were last updated on June 11, 2024.
Scroll through some of the best deals on flights from St. Louis to Porto in 2024. Check back regularly for other flight deals.
Thu 7/49:08 amSTL - OPO
2 stops15h 47mUnited Airlines
Thu 7/119:00 amOPO - STL
1 stop13h 07mUnited Airlines
Deal found 6/11$963
Thu 7/410:19 amSTL - OPO
2 stops14h 36mUnited Airlines
Thu 7/116:00 amOPO - STL
2 stops15h 40mUnited Airlines
Deal found 6/11$1,003
Thu 7/411:25 amSTL - OPO
1 stop13h 30mUnited Airlines
Thu 7/119:00 amOPO - STL
1 stop13h 07mUnited Airlines
Deal found 6/11$1,120
Fri 7/198:35 pmSTL - OPO
3 stops32h 15mMultiple Airlines
Sat 8/312:35 pmOPO - STL
3 stops34h 54mMultiple Airlines
Deal found 6/10$1,250
Fri 7/195:30 pmSTL - OPO
2 stops23h 50mLufthansa
Sat 8/36:00 amOPO - STL
2 stops15h 40mLufthansa
Deal found 6/10$1,336
Fri 7/198:35 pmSTL - OPO
3 stops32h 15mMultiple Airlines
Sat 8/36:10 amOPO - STL
2 stops20h 55mMultiple Airlines
Deal found 6/10$1,354
Fri 7/194:05 pmSTL - OPO
2 stops22h 05mMultiple Airlines
Sat 8/36:10 amOPO - STL
1 stop15h 11mMultiple Airlines
Deal found 6/10$1,514
Fri 7/193:25 pmSTL - OPO
1 stop13h 55mMultiple Airlines
Sat 8/312:35 pmOPO - STL
1 stop16h 10mMultiple Airlines
Deal found 6/10$1,723
Thu 7/410:45 amSTL - OPO
2 stops14h 50mAmerican Airlines
Thu 7/118:15 amOPO - STL
3 stops19h 39mAmerican Airlines
Deal found 6/11$3,858

St. Louis to Porto 2024 flight deals

Discover exclusive flight deals for travel between St. Louis and Porto in 2024. Find excellent offers based on user searches. Over the last 7 days, Cheapflights users made 3,020,828 searches. Data last updated June 11, 2024.
Scroll through some of the best deals on flights from St. Louis to Porto in 2024. Check back regularly for other flight deals.
Sun 11/33:45 pmSTL - OPO
1 stop13h 55mUnited Airlines
Fri 11/156:00 amOPO - STL
2 stops33h 53mUnited Airlines
Deal found 6/10$524
Mon 11/412:58 pmSTL - OPO
2 stops20h 27mUnited Airlines
Fri 11/156:00 amOPO - STL
2 stops33h 53mUnited Airlines
Deal found 6/10$528
Sun 11/33:45 pmSTL - OPO
1 stop13h 55mLufthansa
Fri 11/156:00 amOPO - STL
1 stop13h 55mLufthansa
Deal found 6/10$529
Tue 11/510:40 amSTL - OPO
2 stops19h 00mUnited Airlines
Fri 11/156:00 amOPO - STL
2 stops33h 53mUnited Airlines
Deal found 6/10$530
Mon 11/410:30 amSTL - OPO
2 stops19h 15mAmerican Airlines
Tue 11/128:20 amOPO - STL
3 stops29h 49mAmerican Airlines
Deal found 6/10$538
Mon 11/410:30 amSTL - OPO
2 stops15h 10mAmerican Airlines
Tue 11/128:20 amOPO - STL
2 stops30h 55mAmerican Airlines
Deal found 6/10$539
Tue 11/510:30 amSTL - OPO
2 stops15h 10mIberia
Mon 11/118:40 pmOPO - STL
2 stops30h 51mIberia
Deal found 6/10$544
Sun 11/311:51 amSTL - OPO
2 stops16h 59mDelta
Wed 11/135:00 amOPO - STL
2 stops24h 35mDelta
Deal found 6/10$550
Sun 11/33:45 pmSTL - OPO
1 stop13h 55mUnited Airlines
Thu 11/1412:30 pmOPO - STL
2 stops33h 13mUnited Airlines
Deal found 6/10$556

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 3,020,828 searches. Data last updated June 11, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$524 - $665

Route

Depart

Return

Price

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 11/3

1 stop13h 55m

Porto

Fri 11/15

2 stops33h 53m

$524

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 11/3

1 stop13h 55m

Porto

Fri 11/15

1 stop13h 55m

$529

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Mon 11/4

2 stops19h 15m

Porto

Tue 11/12

3 stops29h 49m

$538

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Tue 11/5

2 stops15h 10m

Porto

Mon 11/11

2 stops30h 51m

$544

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 11/3

2 stops18h 50m

Porto

Fri 11/15

2 stops21h 50m

$550

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Mon 11/4

2 stops17h 04m

Porto

Tue 11/12

2 stops17h 50m

$564

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Mon 11/4

2 stops21h 33m

Porto

Mon 11/11

2 stops30h 51m

$576

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 11/3

2 stops22h 45m

Porto

Mon 11/11

2 stops33h 53m

$601

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 11/3

2 stops19h 51m

Porto

Sat 11/9

2 stops26h 08m

$665

Flights are sorted by cheapest first

Deals found on 6/10

What is the cheapest day to fly from St. Louis to Porto?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to Porto. Price data was last updated on June 2, 2024.
Morning
Noon
Afternoon
Evening
All times are departure.
Travelers seeking maximum savings on their St. Louis to Porto flight should consider departing on Tuesday mornings when fares are most often at their lowest. Monday mornings flights should be avoided if possible as fares are typically the most expensive at this time.
Search Deals

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.

Temperature and rainfall in Porto by month

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

OPO

Temperature

48.2 - 68 °F

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 June 11, 2024.
Read through reviews of airlines operating flights from St. Louis to Porto, such as United Airlines, Lufthansa and American Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
10,277 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.6

Entertainment

8.0

Food

7.4

Reviews

1 / 10

Bad experience with the staff boarding the gate. I couldn’t board with my carry on, personal item and a funny bag. I had to put my passport inside my pockets and put the funny bag inside the personal item. Then after passing the staff pull out everything again.

Delta
8.0
Very good
10,277 reviews
Delta
8.0
Very good
10,277 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.6

Entertainment

8.0

Food

7.4

Reviews

1 / 10

Bad experience with the staff boarding the gate. I couldn’t board with my carry on, personal item and a funny bag. I had to put my passport inside my pockets and put the funny bag inside the personal item. Then after passing the staff pull out everything again.

KLM
7.9
Good
1,470 reviews
Delta
8.0
Very good
10,277 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.6

Entertainment

8.0

Food

7.4

Reviews

1 / 10

Bad experience with the staff boarding the gate. I couldn’t board with my carry on, personal item and a funny bag. I had to put my passport inside my pockets and put the funny bag inside the personal item. Then after passing the staff pull out everything again.

Air France
7.5
Good
1,701 reviews
Delta
8.0
Very good
10,277 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.6

Entertainment

8.0

Food

7.4

Reviews

1 / 10

Bad experience with the staff boarding the gate. I couldn’t board with my carry on, personal item and a funny bag. I had to put my passport inside my pockets and put the funny bag inside the personal item. Then after passing the staff pull out everything again.

United Airlines
7.4
Good
10,647 reviews
Delta
8.0
Very good
10,277 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.6

Entertainment

8.0

Food

7.4

Reviews

1 / 10

Bad experience with the staff boarding the gate. I couldn’t board with my carry on, personal item and a funny bag. I had to put my passport inside my pockets and put the funny bag inside the personal item. Then after passing the staff pull out everything again.

American Airlines
7.3
Good
14,129 reviews
Delta
8.0
Very good
10,277 reviews

Comfort

7.9

Overall

8.0

Boarding

8.2

Crew

8.6

Entertainment

8.0

Food

7.4

Reviews

1 / 10

Bad experience with the staff boarding the gate. I couldn’t board with my carry on, personal item and a funny bag. I had to put my passport inside my pockets and put the funny bag inside the personal item. Then after passing the staff pull out everything again.

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.

  • Can I find flights from St. Louis to Porto for under $600 on Cheapflights?

    Yes, there are multiple flights from St. Louis to Porto for under $600. The cheapest flight booked recently is on United Airlines for just $524, but on average you can expect to pay $558.

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

    United Airlines, at $524, was found to be the cheapest airline from St. Louis to Porto.Alternate airlines to your destination round-trip include Lufthansa and American Airlines. Users have found that United Airlines is 51% cheaper than the other options available to this destination.

  • What does STL to OPO mean?

    These are just IATA (International Air Transport Association) codes. They are used in aviation to identify and differentiate airports. That’s why a Lambert-St Louis Airport to Porto Airport flight would often be abbreviated as a STL to OPO flight.

  • Can I find deals for flights from St. Louis to Porto that include extra baggage allowance?

    The amount of baggage you can bring on your St. Louis to Porto flight depends on the airline and the type of fare you've chosen. After entering your flight details, you'll be able to view the specific baggage policies for each deal in the search results. Keep in mind that certain deals may offer additional baggage allowance.

  • Can I find deals on flights from St. Louis to Porto with specific airlines?

    Yes, Cheapflights allows you to browse and filter St. Louis to Porto flight deals by airline. After entering your origin and destination, use the available filters to view flights offered by airlines.

  • 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.

  • Can I find deals for flights from St. Louis to Porto that allow pets onboard?

    Many airlines flying from St. Louis to Porto offer the option to travel with pets. After selecting a flight deal, you can find more information about the airline's pet policy on their official website or by contacting the airline directly. Please note that additional fees and restrictions may apply.

  • Can I find deals on last-minute flights from St. Louis to Porto?

    Yes, you can often find last-minute deals on St. Louis to Porto flights on Cheapflights. However, these deals can vary and may not always be available. We recommend checking back frequently or signing up for price alerts for the most up-to-date deals.

  • How recently were the St. Louis to Porto flight deals updated?

    The St. Louis to Porto flight deals you see on this page were last updated on 6/10.

  • 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 $524). Flying from St. Louis to Porto in June is currently the most expensive (average of $974). 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.

See more FAQs

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Alternative routes for St. Louis to Porto
See prices for flight routes from nearby airports that may be better suited for you.

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Top 2 airlines flying from St. Louis to Porto

Discover the top 2 airlines 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 3,020,828 searches. Data last updated June 11, 2024.
AirlineCheapestAverageFlexibilityOn-time
IberiaCheapest$624Average$1,001FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$752Average$1,224FlexibilityNo cancel feeOn-time69%
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Search flights from St. Louis to Porto by cabin class

Find flights from St. Louis to Porto, based on your preferred cabin class, be it economy, premium economy, business, or first class.
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