STL - OPO

$365 Find Cheap Flights from St. Louis to Porto - Compare and Save

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Everything you should know

Cheapest round-trip
$590
Typical prices: $712-$1,190
Iberia
Sat 10/27Tue 11/6
STL - OPO • 2 stops
Cheapest one-way
$365
Typical prices: $487-$808
United Airlines
Tue 3/13
STL - OPO • 2 stops
Nonstop flights
Not available
There are currently no direct flights between St. Louis and Porto. You'll need to take a connecting flight to reach the destination.
Insights
Insights
When to travel
January
Cheapest • 45% price drop
August
Most popular
Good to know
+1
Good to know
+1
Top layover airports
Frankfurt am Main (FRA)
Cheapest • Avg $587 (round-trip)
Montreal Pierre Elliott Trudeau Intl (YUL)
Shortest trip • 12h 15m (one-way)
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Insights
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Flight Deals

Cheap Flights from St. Louis to Porto (STL-OPO)

 
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from St. Louis to Porto

Tue, Oct 27 - Fri, Nov 6
American Airlines Logo
1:06 pm - 11:45 amSTL  Lambert-St Louis-OPO Porto
17h 39m2 stops Chicago O'Hare Intl Madrid Barajas
American Airlines Logo
8:20 am - 7:22 pmOPO  Porto-STL Lambert-St Louis
17h 02m2 stops Madrid Barajas Chicago O'Hare Intl
$590American Airlines
Tue, Oct 27 - Fri, Nov 6
Iberia Logo
1:06 pm - 11:45 amSTL  Lambert-St Louis-OPO Porto
17h 39m2 stops Chicago O'Hare Intl Madrid Barajas
Iberia Logo
8:20 am - 6:17 pmOPO  Porto-STL Lambert-St Louis
15h 57m2 stops Madrid Barajas Chicago O'Hare Intl
$590Iberia
Tue, Oct 27 - Tue, Nov 3
Iberia Logo
8:48 am - 11:45 amSTL  Lambert-St Louis-OPO Porto
21h 57m2 stops Dallas/Fort Worth Madrid Barajas
Iberia Logo
8:20 am - 7:22 pmOPO  Porto-STL Lambert-St Louis
17h 02m2 stops Madrid Barajas Chicago O'Hare Intl
$590Iberia
Wed, Nov 18 - Wed, Nov 25
Iberia Logo
1:20 pm - 11:45 amSTL  Lambert-St Louis-OPO Porto
16h 25m2 stops Chicago O'Hare Intl Madrid Barajas
Iberia Logo
8:20 am - 7:27 pmOPO  Porto-STL Lambert-St Louis
17h 07m2 stops Madrid Barajas Chicago O'Hare Intl
$590Iberia
Tue, Oct 27 - Fri, Nov 6
Lufthansa Logo
11:29 am - 9:30 amSTL  Lambert-St Louis-OPO Porto
17h 01m1 stop Newark
Lufthansa Logo
6:15 am - 9:40 pmOPO  Porto-STL Lambert-St Louis
21h 25m2 stops Munich Franz Josef Strauss Chicago O'Hare Intl
$613Lufthansa
Tue, Nov 3 - Tue, Nov 10
United Airlines Logo
7:30 am - 9:30 amSTL  Lambert-St Louis-OPO Porto
20h 00m2 stops Chicago O'Hare Intl Newark
United Airlines Logo
12:35 pm - 1:45 pmOPO  Porto-STL Lambert-St Louis
31h 10m1 stop Frankfurt am Main
$616United Airlines
Tue, Oct 27 - Fri, Nov 6
Lufthansa Logo
1:08 pm - 3:20 pmSTL  Lambert-St Louis-OPO Porto
21h 12m2 stops Chicago O'Hare Intl Frankfurt am Main
Lufthansa Logo
6:00 am - 1:45 pmOPO  Porto-STL Lambert-St Louis
13h 45m1 stop Frankfurt am Main
$628Lufthansa
Wed, Nov 18 - Wed, Nov 25
Lufthansa Logo
3:40 pm - 11:45 amSTL  Lambert-St Louis-OPO Porto
14h 05m1 stop Frankfurt am Main
Lufthansa Logo
6:00 am - 1:45 pmOPO  Porto-STL Lambert-St Louis
13h 45m1 stop Frankfurt am Main
$629Lufthansa
Tue, Oct 27 - Fri, Nov 6
United Airlines Logo
11:29 am - 9:30 amSTL  Lambert-St Louis-OPO Porto
17h 01m1 stop Newark
United Airlines Logo
6:00 am - 1:45 pmOPO  Porto-STL Lambert-St Louis
13h 45m1 stop Frankfurt am Main
$631United Airlines
Tue, Nov 3 - Sun, Nov 8
United Airlines Logo
7:30 am - 9:30 amSTL  Lambert-St Louis-OPO Porto
20h 00m2 stops Chicago O'Hare Intl Newark
United Airlines Logo
6:00 am - 11:24 pmOPO  Porto-STL Lambert-St Louis
23h 24m2 stops Frankfurt am Main Chicago O'Hare Intl
$646United Airlines
Booking Insights

Price, demand and travel trends for St. Louis to Porto flights

Use KAYAK data on prices, travel dates, airlines and seasonal trends to compare options and book flights from St. Louis to Porto with more confidence.

How much is a round-trip flight from St. Louis to Porto?

Round-trip flights from St. Louis to Porto start at $590. Prices are below average for this route right now, with typical round-trip fares ranging from $712 to $1,190. The lowest price found in the past 5 days was $590 on Iberia.

What's the cheapest day of the week to fly from St. Louis to Porto?

Thursday is the cheapest day of the week to fly from St. Louis to Porto, it is 48% cheaper than the average day. Monday is the most expensive day with flight prices 20% higher than average. Based on deals found by KAYAK users in the last 12 months.

Find deals

Key details for St. Louis to Porto flights

Low season

November

Cheapest flight

$365
Best time to beat the crowds with an average 34% drop in price.
Most popular time to fly with an average 9% increase in price.
Flight from St. Louis to Porto

When to book flights from St. Louis to Porto

Are your dates flexible? Find out the best times to travel from St. Louis to Porto based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price

Your St. Louis to Porto flight questions, answered

Find helpful route details based on KAYAK data, including flight times, airports, airlines and booking questions.

  • Which airports can I use when flying from St. Louis to Porto?

    Flights from St. Louis to Porto usually depart from Lambert-St Louis (STL) and arrive at Porto (OPO).

  • What cabin classes can I book on flights from St. Louis to Porto?

    Two cabin classes are available on flights from St. Louis to Porto:

    • Economy Class
    • Premium Economy Class

  • Which airports do connecting flights from St. Louis to Porto pass through?

    One-stop flights from St. Louis to Porto most commonly connect through:

    • Newark (EWR) - 53% of one-stop connections
    • Montreal Pierre Elliott Trudeau Intl (YUL) - 30% of one-stop connections
    • Frankfurt am Main (FRA) - 13% of one-stop connections
    • New York John F Kennedy Intl (JFK) - 3% of one-stop connections

    Newark (EWR) handles the largest share of one-stop connections on this route.

  • Can I save money by using flexible dates for flights from St. Louis to Porto?

    Yes. Being flexible with your travel dates can save you up to 57% on the St. Louis to Porto route. Thursday is the cheapest departure day at $485 round-trip on average, while Monday is the most expensive at $1,127, a difference of $642. KAYAK's flexible dates feature shows options up to 3 days before and after your selected dates, making it easier to compare nearby fares.

  • What popular places can I visit in Porto?

    Some of the most popular sights in Porto are Ribeira, Ribeira Square and Mercado do Bolhão. These are among the most viewed places in Porto on KAYAK.

  • How long is a flight from St. Louis to Porto?

    A nonstop flight from St. Louis to Porto takes 0h 00m, covering 4,154 miles.

  • Do I need a passport to fly from St. Louis to Porto?

    Yes, a valid passport is required for this international route. Many destinations require at least six months of validity beyond your travel dates. Check your passport expiry well before booking.

  • How are flight prices from St. Louis to Porto looking right now?

    One-way fares from St. Louis to Porto are currently lower than usual. Average one-way flight prices are about $539, which is 17% below the typical average for this route.

  • How much time can I save by choosing a different layover airport from St. Louis to Porto?

    Flying via Montreal Pierre Elliott Trudeau Intl (YUL) gives the shortest average 1-stop total travel time at 12h 15m, compared with 12h 57m via New York John F Kennedy Intl (JFK) and 13h 51m via Frankfurt am Main (FRA).

  • What is the time difference between St. Louis and Porto?

    Porto is 6 hours ahead of St. Louis (Western European Time vs Central Time). Plan for the time shift when scheduling connections or first-day activities.

  • What car rental options are available at Porto Airport (OPO)?

    Porto Airport (OPO) hosts 5 major car rental companies, with daily rates starting from around $2 for economy cars. Top options include:
    • Klass Wagen
    • Drive on Holiday
    • GREEN MOTION
    • Goldcar Rental SP
    • SURPRICE CAR RENTAL

  • How much should I expect to pay for a St. Louis to Porto flight?

    Round-trip flights from St. Louis to Porto range from $712 to $1,190, with an average of $932 over the past 12 months. Anything below $712 counts as a good deal.

Your guide to booking St. Louis to Porto flights

Get tips on when to book, when to fly and what to know before your trip.
  • If your dates can be flexible, aim for a Thursday departure instead of Monday. On this route, Thursday flights average $485 - about $642 less than Monday (57% savings) based on the last 12 months.
  • If you can choose when to travel, plan your St. Louis to Porto trip for January. Fares historically average $510 round-trip in that month - typically $676 less than the most expensive month, which is September (based on the last 12 months).
  • If you're arriving late at night and need somewhere to stay, check out these hotels close to Porto Airport.
    - Opo Hotel Porto Aeroporto

More options for your flight from St. Louis to Porto

Complete your trip to Porto with a hotel stay or car rental

Car rentals in Porto
Hotels in Porto
Vacations in Porto