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Cheap flights from St. Louis (STL) to Porto (OPO) from $453

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 7/4. 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 7 — Jun 141
From?
To?
Fri 6/7
Fri 6/14
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 2, 2024.

Popular in

June

Cheapest in

February

Average price

$1,619

Round-trip from

$523
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 Sunday can be a cost-effective option. It’s possible to save up to 51% 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 United Airlines flights from St. Louis to Porto

Explore cheap flight options specifically provided by United Airlines for the route between St. Louis and Porto. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 2,810,401 searches. Data last updated June 2, 2024.
Consider these cheap United Airlines flights we've found departing from St. Louis to Porto. It's recommended that users confirm their flight details before booking.
Sun 9/2211:05 amSTL - OPO
2 stops22h 40mUnited Airlines
Wed 10/26:00 amOPO - STL
3 stops34h 07mUnited Airlines
Deal found 6/1$902
Sat 9/144:51 pmSTL - OPO
2 stops40h 54mUnited Airlines
Wed 9/256:00 amOPO - STL
1 stop13h 30mUnited Airlines
Deal found 5/31$949
Sat 9/144:51 pmSTL - OPO
2 stops40h 54mUnited Airlines
Wed 9/2512:10 pmOPO - STL
3 stops27h 57mUnited Airlines
Deal found 5/31$953
Sat 9/145:20 pmSTL - OPO
3 stops40h 25mUnited Airlines
Wed 9/2512:10 pmOPO - STL
3 stops27h 57mUnited Airlines
Deal found 5/31$959
Sun 9/229:05 amSTL - OPO
2 stops24h 40mUnited Airlines
Wed 10/26:00 amOPO - STL
1 stop13h 30mUnited Airlines
Deal found 6/1$961
Sat 9/145:20 pmSTL - OPO
3 stops34h 25mUnited Airlines
Wed 9/256:00 amOPO - STL
2 stops15h 49mUnited Airlines
Deal found 6/1$971
Fri 10/119:00 amSTL - OPO
2 stops18h 45mUnited Airlines
Mon 10/2112:10 pmOPO - STL
3 stops27h 57mUnited Airlines
Deal found 6/1$1,021
Sun 9/155:32 pmSTL - OPO
1 stop10h 13mUnited Airlines
Thu 9/266:00 amOPO - STL
2 stops39h 20mUnited Airlines
Deal found 5/31$1,121
Sat 9/145:32 pmSTL - OPO
1 stop10h 13mUnited Airlines
Wed 9/256:00 amOPO - STL
1 stop13h 30mUnited Airlines
Deal found 5/31$1,226

Cheap Lufthansa flights from St. Louis to Porto

Explore cheap flight options specifically provided by Lufthansa for the route between St. Louis and Porto. Find affordable fares and compare prices with other airlines to secure the best deal for your journey. Over the last 7 days, Cheapflights users made 2,810,401 searches. Data last updated June 2, 2024.
Browse through some of the cheapest Lufthansa flights traveling from St. Louis to Porto. Check back soon if you're not seeing flights that suit your needs.
Wed 9/118:25 amSTL - OPO
2 stops32h 55mLufthansa
Fri 9/206:00 amOPO - STL
1 stop13h 30mLufthansa
Deal found 6/1$901
Sat 9/145:20 pmSTL - OPO
2 stops24h 00mLufthansa
Wed 9/256:00 amOPO - STL
1 stop13h 30mLufthansa
Deal found 5/31$951
Fri 10/113:25 pmSTL - OPO
1 stop18h 30mLufthansa
Mon 10/216:15 amOPO - STL
2 stops22h 47mLufthansa
Deal found 6/1$969
Sat 9/145:20 pmSTL - OPO
2 stops24h 00mLufthansa
Thu 9/2612:10 pmOPO - STL
1 stop31h 20mLufthansa
Deal found 5/31$1,134
Mon 9/95:20 pmSTL - OPO
2 stops40h 25mLufthansa
Sat 9/2112:10 pmOPO - STL
1 stop31h 20mLufthansa
Deal found 5/31$1,137
Sun 9/83:25 pmSTL - OPO
1 stop13h 55mLufthansa
Fri 9/206:00 amOPO - STL
1 stop13h 30mLufthansa
Deal found 6/1$1,246
Sun 9/812:15 pmSTL - OPO
2 stops16h 40mLufthansa
Fri 9/206:00 amOPO - STL
1 stop13h 30mLufthansa
Deal found 6/1$1,265
Fri 9/63:25 pmSTL - OPO
1 stop13h 55mLufthansa
Fri 9/206:00 amOPO - STL
1 stop13h 30mLufthansa
Deal found 6/1$1,277
Sat 9/712:55 pmSTL - OPO
2 stops16h 25mLufthansa
Fri 9/206:00 amOPO - STL
1 stop13h 30mLufthansa
Deal found 6/1$1,281

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 2,810,401 searches. Data last updated June 2, 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 9/224:05 pmSTL - OPO
2 stops20h 10mAir Canada
Wed 10/28:40 amOPO - STL
2 stops17h 20mAir Canada
Deal found 6/1$812
Wed 9/118:25 amSTL - OPO
2 stops32h 55mMultiple Airlines
Fri 9/208:40 amOPO - STL
2 stops17h 20mMultiple Airlines
Deal found 6/1$870
Tue 9/102:17 pmSTL - OPO
2 stops19h 13mDelta
Fri 9/209:15 amOPO - STL
2 stops17h 32mDelta
Deal found 6/1$886
Mon 9/93:18 pmSTL - OPO
2 stops35h 07mDelta
Fri 9/209:15 amOPO - STL
2 stops17h 32mDelta
Deal found 6/1$887
Sat 9/146:09 pmSTL - OPO
2 stops55h 26mMultiple Airlines
Wed 9/2512:25 pmOPO - STL
2 stops34h 59mMultiple Airlines
Deal found 6/1$896
Fri 10/114:05 pmSTL - OPO
2 stops20h 25mMultiple Airlines
Mon 10/217:15 pmOPO - STL
2 stops31h 50mMultiple Airlines
Deal found 6/1$897
Wed 9/118:25 amSTL - OPO
2 stops32h 55mLufthansa
Fri 9/206:00 amOPO - STL
1 stop13h 30mLufthansa
Deal found 6/1$901
Sun 9/2211:05 amSTL - OPO
2 stops22h 40mUnited Airlines
Wed 10/26:00 amOPO - STL
3 stops34h 07mUnited Airlines
Deal found 6/1$902
Sat 9/1411:38 amSTL - OPO
2 stops13h 57mAmerican Airlines
Thu 9/268:15 amOPO - STL
2 stops19h 54mAmerican Airlines
Deal found 5/31$916

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 2,810,401 searches. Data last updated June 2, 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.
Thu 7/47:29 pmSTL - OPO
2 stops43h 21mMultiple Airlines
Deal found 5/31$453
Thu 7/47:29 pmSTL - OPO
3 stops53h 46mMultiple Airlines
Deal found 5/31$462
Wed 7/37:29 pmSTL - OPO
3 stops55h 16mMultiple Airlines
Deal found 5/31$497
Mon 7/228:58 amSTL - OPO
2 stops18h 47mUnited Airlines
Deal found 5/31$529
Wed 7/37:29 pmSTL - OPO
2 stops44h 36mMultiple Airlines
Deal found 5/31$534
Wed 7/248:05 amSTL - OPO
2 stops16h 50mUnited Airlines
Deal found 6/1$535
Sat 9/285:05 pmSTL - OPO
2 stops16h 25mAir France
Deal found 6/1$546
Sat 9/285:30 pmSTL - OPO
1 stop10h 15mUnited Airlines
Deal found 6/1$614
Wed 7/245:30 pmSTL - OPO
3 stops31h 25mUnited Airlines
Deal found 6/1$649

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 2,810,401 searches. Data last updated June 2, 2024.

Fly from

Any airport

Fly to

Any airport

Budget

$812 - $1,082

Route

Depart

Return

Price

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 9/22

2 stops20h 10m

Porto

Wed 10/2

2 stops17h 20m

$812

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 9/15

2 stops13h 57m

Porto

Thu 9/26

2 stops19h 54m

$866

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Wed 9/11

2 stops32h 55m

Porto

Fri 9/20

2 stops17h 20m

$870

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Tue 9/10

2 stops19h 13m

Porto

Fri 9/20

2 stops20h 24m

$886

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sat 9/14

2 stops35h 26m

Porto

Thu 9/26

2 stops15h 09m

$900

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Wed 9/11

2 stops32h 55m

Porto

Fri 9/20

1 stop13h 30m

$901

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Sun 9/22

2 stops22h 40m

Porto

Wed 10/2

3 stops34h 07m

$902

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Wed 7/3

2 stops17h 28m

Porto

Fri 7/12

2 stops17h 21m

$1,041

Lambert-St LouisPorto

STL - OPO

STLOPO

Lambert-St Louis

Mon 9/9

2 stops33h 15m

Porto

Sun 9/22

2 stops29h 23m

$1,082

Flights are sorted by cheapest first

Deals found on 6/1

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 May 26, 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. Friday afternoons 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

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 2, 2024.
Read through reviews of airlines operating flights from St. Louis to Porto, such as United Airlines, Lufthansa and Air Canada. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Delta
8.0
Very good
10,410 reviews
Check prices

Overall

8.0

Comfort

7.9

Crew

8.6

Entertainment

8.0

Food

7.4

Boarding

8.2

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
10,410 reviews
Delta
8.0
Very good
10,410 reviews
Check prices

Overall

8.0

Comfort

7.9

Crew

8.6

Entertainment

8.0

Food

7.4

Boarding

8.2

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
1,728 reviews
Delta
8.0
Very good
10,410 reviews
Check prices

Overall

8.0

Comfort

7.9

Crew

8.6

Entertainment

8.0

Food

7.4

Boarding

8.2

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
10,754 reviews
Delta
8.0
Very good
10,410 reviews
Check prices

Overall

8.0

Comfort

7.9

Crew

8.6

Entertainment

8.0

Food

7.4

Boarding

8.2

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
14,268 reviews
Delta
8.0
Very good
10,410 reviews
Check prices

Overall

8.0

Comfort

7.9

Crew

8.6

Entertainment

8.0

Food

7.4

Boarding

8.2

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.

Iberia
7.1
Good
2,736 reviews
Delta
8.0
Very good
10,410 reviews
Check prices

Overall

8.0

Comfort

7.9

Crew

8.6

Entertainment

8.0

Food

7.4

Boarding

8.2

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 $900 on Cheapflights?

    Yes, there are multiple flights from St. Louis to Porto for under $900. The cheapest flight booked recently is on Air Canada for just $812, but on average you can expect to pay $906.

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

    Air Canada, at $812, was found to be the cheapest airline from St. Louis to Porto.Alternate airlines to your destination round-trip include American Airlines and Delta. Users have found that Air Canada is 25% 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 $794 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 6/1.

  • 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 $523). Flying from St. Louis to Porto in June is currently the most expensive (average of $994). 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 2,810,401 searches. Data last updated June 2, 2024.
AirlineCheapestAverageFlexibilityOn-time
IberiaCheapest$624Average$1,001FlexibilityNo cancel feeOn-time77%
Search Iberia flights
United AirlinesCheapest$752Average$1,231FlexibilityNo 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.
First Class
Business Class
Prem Econ Class
Economy Class

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Fly with Cheapflights

Find the best flight deals on Cheapflights, where travelers can enjoy low prices and a wide availability of flights to their desired destinations.

How does Cheapflights help users find flights from St. Louis to Porto?

Cheapflights goes through 900+ travel sites to look for the best flight deals for flights from St. Louis to Porto. Too many options? Cheapflights also provides filters for things like airlines, price ranges, and number of stops to help you make a decision easily.

Why should you use Cheapflights to find cheap flight tickets from St. Louis to Porto?

By finding flights from multiple airlines and providers at completely no cost, Cheapflights helps millions of users like you annually find the best flights to Porto from St. Louis.

Can Cheapflights find flights from St. Louis to Porto with no change fees?

Need flexible booking options for your flight to Porto from St. Louis? Don’t worry, Cheapflights have you covered. Use our search filter to only show flights with no change fees.

Can Cheapflights notify me if prices for flights from St. Louis to Porto become cheaper?

Yes, Cheapflights has a feature called Price Alert, which notifies users when flight prices change. Track prices for your flight to Porto from St. Louis today and book when prices fit your budget.

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