$113 Cheap Flights from St. Louis (STL) to San Juan (SJU)

View $113 flight on Tue, Oct 21, 2025Opens in a new window

Popular airlines from St. Louis Lambert Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)

Cheap Flights from St. Louis to San Juan (STL-SJU)

Prices were available within the past 7 days and start at $113 for one-way flights and $220 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

American Airlines
Tue, Oct 28 - Wed, Oct 29
STL
St. Louis
SJU
San Juan
$220 Roundtrip, found 5 days ago
$220
Roundtrip
found 5 days ago
Select American Airlines flight, departing Tue, Oct 28 from St. Louis to San Juan, returning Wed, Oct 29, priced at $220 found 5 days ago
United
Fri, Oct 31 - Sat, Nov 1
STL
St. Louis
SJU
San Juan
$220 Roundtrip, found 1 day ago
$220
Roundtrip
found 1 day ago
Select United flight, departing Fri, Oct 31 from St. Louis to San Juan, returning Sat, Nov 1, priced at $220 found 1 day ago
Southwest Airlines
Tue, Nov 4 - Sat, Nov 8
STL
St. Louis
SJU
San Juan
$221 Roundtrip, found 3 days ago
$221
Roundtrip
found 3 days ago
Select Southwest Airlines flight, departing Tue, Nov 4 from St. Louis to San Juan, returning Sat, Nov 8, priced at $221 found 3 days ago
American Airlines
Tue, Nov 4 - Sat, Nov 8
STL
St. Louis
SJU
San Juan
$224 Roundtrip, found 3 days ago
$224
Roundtrip
found 3 days ago
Select American Airlines flight, departing Tue, Nov 4 from St. Louis to San Juan, returning Sat, Nov 8, priced at $224 found 3 days ago
Delta
Mon, Nov 10 - Thu, Nov 13
STL
St. Louis
SJU
San Juan
$225 Roundtrip, just found
$225
Roundtrip
just found
Select Delta flight, departing Mon, Nov 10 from St. Louis to San Juan, returning Thu, Nov 13, priced at $225 just found
American Airlines
Fri, Dec 5 - Sat, Dec 13
STL
St. Louis
SJU
San Juan
$227 Roundtrip, found 2 days ago
$227
Roundtrip
found 2 days ago
Select American Airlines flight, departing Fri, Dec 5 from St. Louis to San Juan, returning Sat, Dec 13, priced at $227 found 2 days ago
American Airlines
Tue, Oct 21 - Tue, Oct 28
STL
St. Louis
SJU
San Juan
$228 Roundtrip, just found
$228
Roundtrip
just found
Select American Airlines flight, departing Tue, Oct 21 from St. Louis to San Juan, returning Tue, Oct 28, priced at $228 just found
American Airlines
Wed, Dec 10 - Sun, Dec 14
STL
St. Louis
SJU
San Juan
$229 Roundtrip, found 1 hour ago
$229
Roundtrip
found 1 hour ago
Select American Airlines flight, departing Wed, Dec 10 from St. Louis to San Juan, returning Sun, Dec 14, priced at $229 found 1 hour ago
United
Sat, Oct 25 - Sat, Nov 1
STL
St. Louis
SJU
San Juan
$230 Roundtrip, found 5 hours ago
$230
Roundtrip
found 5 hours ago
Select United flight, departing Sat, Oct 25 from St. Louis to San Juan, returning Sat, Nov 1, priced at $230 found 5 hours ago
Frontier Airlines
Wed, Nov 19 - Thu, Nov 27
STL
St. Louis
SJU
San Juan
$253 Roundtrip, found 5 days ago
$253
Roundtrip
found 5 days ago
Select Frontier Airlines flight, departing Wed, Nov 19 from St. Louis to San Juan, returning Thu, Nov 27, priced at $253 found 5 days ago

Find the cheapest month to fly from St. Louis (STL) to San Juan (SJU)

January is typically the cheapest month to fly

From $153 - $492 per traveler.

Alternative airports near San Juan

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Luis Munoz Marin Intl. SJU. Cheapest option available. Average driving time to city center is 16 minutes. Flights from $488
SJU
Luis Munoz Marin Intl.
Cheapest
Average driving time to city center16 min
Flights from $488

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU) cost?
Snag a cheap one-way flight from $113 or cheap return flight from $220 from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to find our cheapest flight offers on this route.
What is the cheapest month to fly from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
Flying in October may help you find better deals, as it's the cheapest month for flights between STL and SJU. You'll usually find the lowest prices during the off-season.
Which airlines fly direct from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
Board a nonstop flight with Southwest Airlines and head straight from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU).
What is the cheapest airline that flies from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
Use the filters on Expedia to compare airlines and find the most affordable carrier that'll fly you from STL to SJU. Then, sort your results by "Price (lowest to highest)" to score a good deal.
How many flights per day from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
On average, there are 1 nonstop flights taking off from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU) every week. If you don't find one that works for your schedule, consider a flight that has a layover. Customize your search results on Expedia to include one or more stops and opt for the best alternative.
What are the most popular departure times for flights from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
The 12 PM departures from STL to SJU see the highest demand. Greater demand means you'll likely pay more for these departures. If you're hoping to save money, book during off-peak hours.
What day of the week has the most flights from STL to SJU?
Travel on a Saturday if you're searching for the largest selection of flights from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU).
What is the earliest flight from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
Hop on the earliest flight at around 12:50PM UTC-6, departing from Lambert-St. Louis Intl. Airport (STL). You'll be in the air for about 4h 15m, coming in to land at Luis Munoz Marin Intl. Airport (SJU) at approximately 7:05PM UTC-4.
How long does it take to fly from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
The average flight duration from STL to SJU is 4 hours and 15 minutes, covering a total distance of 2,000 mi.
What airline has the least delays from STL to SJU?
Southwest Airlines has the best track record for on-time direct flights from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU), with an on-time score of 100%. Use the Expedia App to view your journey status before you head off and get notified of any changes.
What is the best time to fly from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
Choose a flight from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU) that takes off before 3 PM to reduce the risk of cancellations. Departures after this hour are on average 22% more likely to be canceled.**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.
What airports do you fly into for San Juan from Lambert-St. Louis Intl. Airport (STL)?
Luis Munoz Marin Intl. Airport (SJU) is the only airport in San Juan with direct flights from Lambert-St. Louis Intl. Airport (STL). Explore the options and discover cheap fares on Expedia.
Is it cheaper to buy a plane ticket from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU) last-minute?
Last-minute fares from STL to SJU are typically more expensive. To secure the cheapest rates, start looking for flights well in advance. That said, if you're flexible with your travel dates, you may land a cheap ticket right before your journey.
Can I cancel or change the date of my flight from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU)?
In most cases, you can modify or cancel your STL to SJU flight. However, there may be additional charges, especially if you made your booking over 24 hours ago. Double-check your itinerary for the airline's fees and policies on flight changes, or if you need more details, go to our Customer Service portal.

Travel information

Travel information

0
Origin airport
Lambert-St. Louis Intl.
Destination airport
Luis Munoz Marin Intl.
Airlines serving
American Airlines, Delta, Frontier Airlines, Southwest Airlines, United
Roundtrip price
$219
Distance
2024 mi

Book with confidence

Book with confidence

St. Louis to San Juan Flights

The cheapest times to fly from St. Louis to San Juan

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 St. Louis to San Juan are during the month of October. You can find some of the cheapest flights from St. Louis to San Juan with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from St. Louis to San Juan

Sunday is one of the best days to book for cheap flights from St. Louis to San Juan: 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 St. Louis to San Juan

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 St. Louis to San Juan in 2025. You can also book with separate airlines for your outbound and return journeys, from $113 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 St. Louis to San Juan 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 St. Louis to San Juan 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.

 

St. Louis to San Juan Flights

Explore a world of travel with Expedia

Explore a world of travel with Expedia

*Available to One Key members.