$304 Cheap Flights from Port of Spain (POS) to St. Louis (STL)

View $304 flight on Mon, Oct 20, 2025Opens in a new window

Popular airlines from Piarco Intl. Airport (POS) to St. Louis Lambert Intl. Airport (STL)

Cheap Flights from Port of Spain to St. Louis (POS-STL)

Prices were available within the past 7 days and start at $304 for one-way flights and $561 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Air Canada
Tue, Jun 10 - Fri, Jun 13
POS
Trinidad
STL
St. Louis
$561 Roundtrip, found 1 day ago
$561
Roundtrip
found 1 day ago
Select Air Canada flight, departing Tue, Jun 10 from Trinidad to St. Louis, returning Fri, Jun 13, priced at $561 found 1 day ago
Air Canada
Mon, May 5 - Mon, May 12
POS
Trinidad
STL
St. Louis
$602 Roundtrip, found 1 day ago
$602
Roundtrip
found 1 day ago
Select Air Canada flight, departing Mon, May 5 from Trinidad to St. Louis, returning Mon, May 12, priced at $602 found 1 day ago
Air Canada
Mon, May 5 - Mon, May 12
POS
Trinidad
STL
St. Louis
$608 Roundtrip, found 1 day ago
$608
Roundtrip
found 1 day ago
Select Air Canada flight, departing Mon, May 5 from Trinidad to St. Louis, returning Mon, May 12, priced at $608 found 1 day ago
United
Thu, Sep 18 - Sun, Sep 21
POS
Trinidad
STL
St. Louis
$612 Roundtrip, found 11 hours ago
$612
Roundtrip
found 11 hours ago
Select United flight, departing Thu, Sep 18 from Trinidad to St. Louis, returning Sun, Sep 21, priced at $612 found 11 hours ago
American Airlines
Fri, Jul 11 - Fri, Jul 25
POS
Trinidad
STL
St. Louis
$617 Roundtrip, found 18 hours ago
$617
Roundtrip
found 18 hours ago
Select American Airlines flight, departing Fri, Jul 11 from Trinidad to St. Louis, returning Fri, Jul 25, priced at $617 found 18 hours ago
Air Canada
Tue, Jun 10 - Fri, Jun 13
POS
Trinidad
STL
St. Louis
$617 Roundtrip, found 1 day ago
$617
Roundtrip
found 1 day ago
Select Air Canada flight, departing Tue, Jun 10 from Trinidad to St. Louis, returning Fri, Jun 13, priced at $617 found 1 day ago
American Airlines
Thu, Sep 18 - Sun, Sep 21
POS
Trinidad
STL
St. Louis
$619 Roundtrip, found 11 hours ago
$619
Roundtrip
found 11 hours ago
Select American Airlines flight, departing Thu, Sep 18 from Trinidad to St. Louis, returning Sun, Sep 21, priced at $619 found 11 hours ago
United
Thu, Sep 18 - Sun, Sep 21
POS
Trinidad
STL
St. Louis
$621 Roundtrip, found 11 hours ago
$621
Roundtrip
found 11 hours ago
Select United flight, departing Thu, Sep 18 from Trinidad to St. Louis, returning Sun, Sep 21, priced at $621 found 11 hours ago
American Airlines
Thu, Jul 3 - Mon, Jul 14
POS
Trinidad
STL
St. Louis
$623 Roundtrip, found 4 days ago
$623
Roundtrip
found 4 days ago
Select American Airlines flight, departing Thu, Jul 3 from Trinidad to St. Louis, returning Mon, Jul 14, priced at $623 found 4 days ago
United
Sun, Oct 5 - Sat, Oct 11
POS
Trinidad
STL
St. Louis
$626 Roundtrip, found 21 hours ago
$626
Roundtrip
found 21 hours ago
Select United flight, departing Sun, Oct 5 from Trinidad to St. Louis, returning Sat, Oct 11, priced at $626 found 21 hours ago
Flights from Port of Spain (POS) to St. Louis (STL)
Origin airport
Piarco Intl.
Destination airport
Lambert-St. Louis Intl.
Airlines serving
Air Canada, American Airlines, Copa, United
Roundtrip price
$561
Distance
2641 mi

Port of Spain to St. Louis Flights

The cheapest times to fly from Port of Spain to St. Louis

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Port of Spain to St. Louis are during the month of June. You can find some of the cheapest flights from Port of Spain to St. Louis with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Port of Spain to St. Louis

Sunday is one of the best days to book for cheap flights from Port of Spain to St. Louis: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Port of Spain to St. Louis

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Port of Spain to St. Louis in 2025. You can also book with separate airlines for your outbound and return journeys, from $304 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Port of Spain to St. Louis flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Port of Spain to St. Louis airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Frequently asked questions

How much does a flight from Piarco Intl. Airport (POS) to Lambert-St. Louis Intl. Airport (STL) cost?
Discover the latest flight deals from POS to STL by entering your preferred travel dates and searching on Expedia. Easily compare prices by departure date if you have flexibility with your schedule and use handy filters to explore prices for your preferred journey. As a member of One Key™, our free loyalty program, you can use Price Tracking to watch fares and receive notifications if prices go up or down.
What is the cheapest month to fly from POS to STL?
The cheapest flights from POS to STL are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
What is the cheapest airline that flies from POS to STL?
Use the filter tool on Expedia to compare airlines and find the cheapest carrier that’ll take you from POS to STL. Sort your results by “Price (lowest to highest)” to snap up a great deal.
How many flights per day from Piarco Intl. Airport (POS) to Lambert-St. Louis Intl. Airport (STL)?
You’ll need to book a flight with a layover when traveling from Piarco Intl. Airport (POS) to Lambert-St. Louis Intl. Airport (STL). There are no daily direct flights on this route. However, just filter your search to include one or two stops to find the best option for your trip.
What day of the week has the most flights from POS to STL?
Usually you’ll find the most flight options available on a Friday. Tuesdays are often the quietest.* However, this can change depending on the time of year, airline and other factors.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from Piarco Intl. Airport (POS) to Lambert-St. Louis Intl. Airport (STL)?
Select a flight from Piarco Intl. Airport (POS) to Lambert-St. Louis Intl. Airport (STL) that takes off before 3 PM to reduce the likelihood of delays and cancellations. Later departures have a 22% higher chance of being canceled, on average.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG’s global flight data platform.
Is it cheaper to buy a plane ticket from Piarco Intl. Airport (POS) to Lambert-St. Louis Intl. Airport (STL) last-minute?
Booking your ticket from POS to STL just before your journey is generally more expensive. But if there’s some wiggle room with your itinerary, you could bag a cheap last-minute fare.
Is it cheaper to book a POS to STL flight and hotel package?
Opting for a POS to STL flight and hotel package is usually cheaper than booking separately. With Expedia, you can enjoy the ease of organizing your trip in one place. Pick from our wide range of stays and then add flights, activities and car rentals to your booking. Bundle everything together, and you could save hundreds of dollars.
Can I cancel or change the date of my flight from Piarco Intl. Airport (POS) to Lambert-St. Louis Intl. Airport (STL)?
If you booked your POS to STL flight within the last 24 hours, you may be able to cancel or modify it without fees. Depending on the airline and the type of fare you have, additional charges may apply for changes beyond that time. Airline policies and contact information can be found in your itinerary or confirmation email. Or, visit our Customer Service portal if you want more information.

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*Available to One Key members.