Cheap flights from St. Louis to Porto from $424
This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to Porto departing on 9/7. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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American Airlines flights from St. Louis to Porto
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Lufthansa flights from St. Louis to Porto
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How to get the cheapest flight ticket from St. Louis to Porto
Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip
What is the cheapest month to fly to Porto?
The month of November is, on average, the cheapest month to fly to Porto from St. Louis, with most prices found around $565. If you aren’t able to travel during the month of November, then book flights to Porto from St. Louis during February instead. Flights to Porto in February, while not as cheap as those in November, still average around $706.
What is the cheapest day to depart on your flight to Porto?
The cheapest day to depart on your flight to Porto is on a Thursday when prices can be found for as low as $752. This is often the case because there is less demand to fly during this day of the week. If your travel schedule is flexible, try to avoid departing on a Friday because tickets tend to average around $1,465. These prices are subject to change though, so be sure to set up a Price Alert for flights to Porto.
What is the cheapest time of day to depart on your flight to Porto?
At noon is the cheapest time of day to fly from St. Louis to Porto when you can find flight prices for as low as $752. Flying to Porto at noon is an ideal time because this is during off-peak travel hours. If you have a flexible travel schedule, then try to avoid flying in the afternoon when prices are $1,170 on average. Flights to Porto from St. Louis in the afternoon are generally more expensive because this time of day is more convenient for travelers’ schedules.
Can stopping save me money on St. Louis to Porto flights?
You could potentially save up to 47% on your flight if you consider stops on a St. Louis to Porto flight.
What is the cheapest airline that flies from Lambert-St Louis to Porto?
British Airways, Scandinavian Airlines, and United Airlines are the most popular carriers operating from Lambert-St Louis to Porto
What airlines fly to Porto?
United Airlines, Lufthansa and Delta are the top three most popular airlines that fly to Porto from St. Louis according to our data. United Airlines is the first choice among our users, with 60% of people opting to fly with this airline when traveling to Porto. Keep in mind that there are 3 different airlines that fly to Porto on a routine basis, so you have a few additional options to choose from.
When to book flights from St. Louis to Porto
Cheap St. Louis to Porto (STL to OPO) flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Porto
How far is Lambert-St Louis to Porto by plane?
There are 4156.0 mi between Lambert-St Louis and Porto. A reasonable flight in good conditions will take 10h 21m.
When did momondo last update prices for flights from Lambert-St Louis Airport to Porto Airport?
Prices for flights from Lambert-St Louis Airport to Porto Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Lambert-St Louis Airport to Porto Airport?
The number of operators available for flights from Lambert-St Louis Airport to Porto Airport is 3 as of June 2025.
How old do you have to be to fly from Lambert-St Louis Airport to Porto Airport?
The minimum age a child must be to fly alone is five but airlines that offer an unaccompanied minor (UNMR) service will have their own age restrictions, including rules around flight length, timings, and stopovers. We always recommend checking with the individual airline you are booking with to travel from Lambert-St Louis Airport to Porto Airport.
What documentation or ID do you need to fly to Porto Airport?
The travel and health documents you'll need for your trip to Porto Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at Porto Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
What is the most popular airline from St. Louis to Porto?
Based on momondo bookings for this flight route, the most popular airline on flight routes from St. Louis to Porto is United Airlines (60% of total bookings). The next most popular airlines are Lufthansa (24%) and Delta (17%).
Best airlines flying from St. Louis to Porto
Compare and see reviews for airlines that fly from St. Louis to Porto with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $612 | Free Cancellation | Rating 6.8 7,148 reviews | |||
| PriceFrom $713 | Free Cancellation | Rating 8.0 7,963 reviews | |||
| PriceFrom $751 | Free Cancellation | Rating 7.4 8,801 reviews |
Traveling to a place near Porto?
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Why should I use momondo to find a flight deal from St. Louis to Porto?
Finding the right flight to Porto from St. Louis is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Porto quick and easy, saving you time and money.
Can I find flights from St. Louis to Porto with flexible booking policies on momondo?
All flight searches from St. Louis to Porto on momondo can be filtered to show those which offer flexible booking policies.
How can momondo help me find flights from St. Louis to Porto?
momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from St. Louis to Porto.
I’m not ready to book a flight from St. Louis to Porto right now. Can momondo alert me if prices change?
Price alerts on flights to Porto from St. Louis are quick and easy to set up on momondo. Simply perform a search and select the price alert feature. It is as simple as that.