$105 Cheap Flights from St. Louis (STL) to San Juan (SJU)

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

Prices were available within the past 7 days and start at $105 for one-way flights and $209 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Delta
American Airlines
United
American Airlines
United
United
Delta
American Airlines
Spirit Airlines
Frontier Airlines

Frequently asked questions

How much does a flight from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU) cost?
Cheap return fares from Lambert-St. Louis Intl. Airport (STL) to Luis Munoz Marin Intl. Airport (SJU) start at $521. This information is based on the cheapest price found on Expedia for this return journey departing within the next three months. This airfare is for a Southwest Airlines flight leaving STL on May 3 2025 and touching down at SJU. The price was last updated on April 24 2025 and has not changed since.
What is the cheapest month to fly from STL to SJU?
The cheapest flights from STL to SJU are usually during off-peak season, when demand is lower. To save money, avoid flying during public holidays, school breaks and major local events.
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 STL to SJU?
With fares starting at $323 for a one-way flight from STL to SJU, Southwest Airlines is currently the cheapest airline on this route. This fare is based on the lowest price found on Expedia departing within the next three months. The flight takes off from STL on April 26 2025. Prices were last updated on April 24 2025 and have not changed since.
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.
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