Cheap flights from St. Louis to Portugal from $346
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 Portugal departing on 9/12. 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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How to get the cheapest flight ticket from St. Louis to Portugal
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 Portugal?
The cheapest month to fly to Portugal from St. Louis is in November. Flight prices, which tend to average around $641, are often lower during this time because this is during the off-season. If you aren’t able to travel during the month of November, then book flights to Portugal from St. Louis during February instead. Flights to Portugal in February, while not as cheap as those in November, still average around $672.
What is the cheapest day to depart on your flight to Portugal?
According to our data, Monday is the cheapest day to fly to Portugal from St. Louis. The lowest ticket price found for a Monday departure recently was $894. Keep in mind that prices can always vary depending on your route and whether or not you are flying domestic or international. The most expensive day to fly to Portugal is Thursday, with ticket prices averaging around $1,087.
What is the cheapest time of day to depart on your flight to Portugal?
Our most recent data shows that the best time of day to fly to Portugal is at noon. Flights from St. Louis to Portugal during this time can be as low as $884. In the afternoon is when there is more demand to fly to Portugal, so prices are often more expensive at around $1,083 per ticket.
How far in advance should I book a flight to Portugal?
You are more likely to see cheaper flights to Portugal from St. Louis when booking 16 weeks ahead of your departure date. In general, you can expect to find flights to Portugal for around $964 when searching 16 weeks out.However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Portugal from St. Louis for as low as $884 on momondo.
What is the cheapest airline that flies from Lambert-St Louis to Portugal?
American Airlines, British Airways, and United Airlines are the most popular carriers operating from Lambert-St Louis to Portugal
What airlines fly to Portugal?
United Airlines, Air Canada and American Airlines are the top three most popular airlines that fly to Portugal from St. Louis according to our data. United Airlines is the first choice among our users, with 41% of people opting to fly with this airline when traveling to Portugal. Keep in mind that there are 7 different airlines that fly to Portugal on a routine basis, so you have a few additional options to choose from.
Cheap St. Louis to Portugal flight deals and tips
Find info about flight duration, direct flights, and airports for your flight from St. Louis to Portugal
When did momondo last update prices for flights from Lambert-St Louis Airport to Portugal?
Prices for flights from Lambert-St Louis Airport to Portugal are refreshed on a daily basis.
How many operators does momondo search for flights from Lambert-St Louis Airport to Portugal?
The number of operators available for flights from Lambert-St Louis Airport to Portugal is 7 as of June 2025.
How old do you have to be to fly from Lambert-St Louis Airport to Portugal?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to Portugal.
What documentation or ID do you need to fly to Portugal?
The travel and health documents you'll need for your trip to Portugal 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 Portugal. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.
Best airlines flying from St. Louis to Portugal
Compare and see reviews for airlines that fly from St. Louis to Portugal with momondo
| Airline | Rating | Free Cancellation | Price | ||
|---|---|---|---|---|---|
| PriceFrom $566 | Free Cancellation | Rating 7.0 2,776 reviews | |||
| PriceFrom $601 | Free Cancellation | Rating 6.7 7,139 reviews | |||
| PriceFrom $602 | Free Cancellation | Rating 7.4 8,790 reviews | |||
| PriceFrom $618 | Free Cancellation | Rating 7.2 10,000 reviews | |||
| PriceFrom $642 | Free Cancellation | Rating 6.6 7,008 reviews | |||
| PriceFrom $680 | Free Cancellation | Rating 8.0 7,946 reviews | |||
| PriceFrom $786 | Free Cancellation | Rating 7.1 9,537 reviews |
Why use momondo?
Why should I use momondo to find a flight deal from St. Louis to Portugal?
It is quick and easy to find St. Louis to Portugal flights on momondo. We search and return numerous flight options from various airlines and agents. You can then use our filters to narrow your search until you have found the most convenient flight to Portugal that suits you.
Can I find flights from St. Louis to Portugal with flexible booking policies on momondo?
Yes. momondo allows you to filter the results for St. Louis to Portugal flights to just show those with flexible booking policies.
How can momondo help me find flights from St. Louis to Portugal?
Once you have performed a search for St. Louis to Portugal flights, momondo helps you find the right one by offering useful filters to narrow down your flight selection. Flights can be filtered by multiple factors such as airline, airport and price; but also by other criteria like aircraft type and payment method.
I’m not ready to book a flight from St. Louis to Portugal right now. Can momondo alert me if prices change?
If you are not ready to book a flight from St. Louis to Portugal now, use our insights above to find helpful tips or alternatively set up a price alert, where momondo will track prices on flights to Portugal and let you know when they change.