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Cheap flights from St. Louis (STL) to Porto (OPO) from $418

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 7/3. 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. 12 — jun. 191
From?
To?
mié. 6/12
mié. 6/19
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 junio 7, 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.

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 3,048,502 searches. Data last updated junio 7, 2024.
Scroll through some of the best deals on flights from St. Louis to Porto in 2024. Check back regularly for other flight deals.
vie. 11/14:45 pmSTL - OPO
1 stop17h 40mUnited Airlines
mar. 11/1912:30 pmOPO - STL
2 stops51h 23mUnited Airlines
Deal found 6/6$591
vie. 11/14:45 pmSTL - OPO
1 stop13h 55mLufthansa
mar. 11/194:30 pmOPO - STL
1 stop27h 25mLufthansa
Deal found 6/6$596
vie. 11/15:37 pmSTL - OPO
2 stops23h 48mLufthansa
mar. 11/191:45 pmOPO - STL
2 stops30h 10mLufthansa
Deal found 6/6$646
jue. 8/1511:09 amSTL - OPO
2 stops18h 36mIberia
lun. 8/194:35 pmOPO - STL
2 stops33h 12mIberia
Deal found 6/6$870
lun. 9/96:22 pmSTL - OPO
3 stops31h 13mAmerican Airlines
sáb. 9/218:15 amOPO - STL
2 stops30h 45mAmerican Airlines
Deal found 6/6$929
lun. 9/96:51 pmSTL - OPO
2 stops30h 44mAmerican Airlines
sáb. 9/218:15 amOPO - STL
2 stops30h 45mAmerican Airlines
Deal found 6/6$932
jue. 8/1511:25 amSTL - OPO
1 stop13h 30mUnited Airlines
lun. 8/196:00 amOPO - STL
2 stops19h 47mUnited Airlines
Deal found 6/6$955
vie. 11/16:22 amSTL - OPO
2 stops24h 23mAmerican Airlines
mar. 11/198:20 amOPO - STL
3 stops29h 49mAmerican Airlines
Deal found 6/6$963
lun. 9/95:20 pmSTL - OPO
2 stops47h 30mLufthansa
sáb. 9/214:45 pmOPO - STL
1 stop26h 45mLufthansa
Deal found 6/6$1,283

One-way flights to Porto from St. Louis

Search for one-way flight options from St. Louis to Porto. Find affordable one-way fares based on user searches. Compare prices and availability to plan your one-way journey according to your preferred dates and budget. Over the last 7 days, Cheapflights users made 3,048,502 searches. Data last updated junio 7, 2024.
Take a look at some of the one-way flights we've detected from St. Louis to Porto. Users in need of a round-trip flight from St. Louis to Porto instead should update the search form at the top of page.
mié. 7/37:29 pmSTL - OPO
3 stops59h 46mMultiple Airlines
Deal found 6/6$418
mié. 7/37:29 pmSTL - OPO
3 stops54h 06mMultiple Airlines
Deal found 6/6$432
mié. 7/37:29 pmSTL - OPO
2 stops44h 36mMultiple Airlines
Deal found 6/6$448
mié. 7/37:29 pmSTL - OPO
2 stops42h 16mMultiple Airlines
Deal found 6/6$472
mié. 7/2410:32 pmSTL - OPO
2 stops42h 38mMultiple Airlines
Deal found 6/6$498
lun. 7/2210:19 amSTL - OPO
2 stops14h 36mUnited Airlines
Deal found 6/6$529
lun. 7/225:30 pmSTL - OPO
3 stops31h 25mUnited Airlines
Deal found 6/6$535
sáb. 7/205:34 pmSTL - OPO
2 stops15h 56mAir France
Deal found 6/6$546
mar. 7/237:33 pmSTL - OPO
3 stops31h 27mMultiple Airlines
Deal found 6/6$559

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 3,048,502 searches. Data last updated junio 7, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$591 - $1,283

Route

Depart

Return

Price

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

vie. 11/1

1 stop17h 40m

Porto

mar. 11/19

2 stops51h 23m

$591

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

vie. 11/1

1 stop13h 55m

Porto

mar. 11/19

1 stop27h 25m

$596

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

vie. 11/1

2 stops23h 48m

Porto

mar. 11/19

2 stops30h 10m

$646

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

jue. 8/15

2 stops18h 36m

Porto

lun. 8/19

2 stops33h 12m

$870

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

lun. 9/9

3 stops31h 13m

Porto

sáb. 9/21

2 stops30h 45m

$929

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

lun. 9/9

2 stops30h 44m

Porto

sáb. 9/21

2 stops30h 45m

$932

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

jue. 8/15

1 stop13h 30m

Porto

lun. 8/19

2 stops19h 47m

$955

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

vie. 11/1

2 stops24h 23m

Porto

mar. 11/19

3 stops29h 49m

$963

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

lun. 9/9

2 stops47h 30m

Porto

sáb. 9/21

1 stop26h 45m

$1,283

Flights are sorted by cheapest first

Deals found on 6/6

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.
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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 junio 7, 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.
Air France
7.5
Good
1,720 reviews

Food

7.1

Boarding

7.5

Comfort

7.4

Crew

8.2

Entertainment

7.1

Overall

7.5

Reviews

1 / 10

Severely delayed on tarmac in Chicago, lost and damaged luggage in the end.

Air France
7.5
Good
1,720 reviews
Air France
7.5
Good
1,720 reviews

Food

7.1

Boarding

7.5

Comfort

7.4

Crew

8.2

Entertainment

7.1

Overall

7.5

Reviews

1 / 10

Severely delayed on tarmac in Chicago, lost and damaged luggage in the end.

United Airlines
7.4
Good
10,696 reviews
Air France
7.5
Good
1,720 reviews

Food

7.1

Boarding

7.5

Comfort

7.4

Crew

8.2

Entertainment

7.1

Overall

7.5

Reviews

1 / 10

Severely delayed on tarmac in Chicago, lost and damaged luggage in the end.

American Airlines
7.3
Good
14,226 reviews
Air France
7.5
Good
1,720 reviews

Food

7.1

Boarding

7.5

Comfort

7.4

Crew

8.2

Entertainment

7.1

Overall

7.5

Reviews

1 / 10

Severely delayed on tarmac in Chicago, lost and damaged luggage in the end.

Iberia
7.1
Good
2,721 reviews
Air France
7.5
Good
1,720 reviews

Food

7.1

Boarding

7.5

Comfort

7.4

Crew

8.2

Entertainment

7.1

Overall

7.5

Reviews

1 / 10

Severely delayed on tarmac in Chicago, lost and damaged luggage in the end.

Lufthansa
7.0
Good
7,525 reviews
Air France
7.5
Good
1,720 reviews

Food

7.1

Boarding

7.5

Comfort

7.4

Crew

8.2

Entertainment

7.1

Overall

7.5

Reviews

1 / 10

Severely delayed on tarmac in Chicago, lost and damaged luggage in the end.

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 $591, but on average you can expect to pay $862.

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

    United Airlines, at $591, was found to be the cheapest airline from St. Louis to Porto.Alternate airlines to your destination round-trip include Lufthansa and Iberia. Users have found that United Airlines is 45% cheaper than the other options available to this destination.

  • What are the cheapest airlines to fly from St. Louis to Porto one-way?

    For one-way options, check prices for United Airlines. According to our data, you can fly for as low as $529. Users have also found prices from $546 and $779 on Air France and Lufthansa, respectively.

  • 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 6/6.

  • 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 $986). 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 3,048,502 searches. Data last updated junio 7, 2024.
AirlineCheapestAverageFlexibilityOn-time
IberiaCheapest$624Average$1,001FlexibilityNo cancel feeOn-time77%
United AirlinesCheapest$752Average$1,226FlexibilityNo 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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