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San Juan

$96+ Cheap flights from St. Louis (STL) to San Juan

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 7/6. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SJU
Jun 17 — Jun 241
Tue 6/17
Tue 6/24
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to San Juan are usually found in September or August, booked 71 days in advance, depart on a Wednesday or Tuesday and return on a Tuesday

Cheap flight deals from St. Louis to San Juan

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to San Juan (PR1). Learn about various techniques such as flexible date searches, comparing prices across and setting up price alerts. Use these methods to find the cheapest flights available for your travel needs. Data last updated June 12, 2025.

Round-trip from

$197
(Priceline)

One-way from

$96
(Booking.com)

Popular in

June

Cheapest in

September

Average price

$552
From Lambert-St Louis to San Juan
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One-way flight from Lambert-St Louis to San Juan
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Highest demand for flights based on searches. 15% potential increase in price ($83 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($11 potential savings vs. average RT price).
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Average for round-trip flights in June 2025
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Find flight deals from St. Louis to San Juan

Cheapest flights from St. Louis to San Juan
Explore the most affordable flight options available from St. Louis to San Juan. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2025.

This Priceline deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/92:22 pmSTL - SJU
1 stop8h 32mFrontier
Sat 10/113:40 amSJU - STL
1 stop10h 47mFrontier
Deal found 6/10$197
This Delta deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/911:51 amSTL - SJU
1 stop9h 26mDelta
Fri 12/123:25 pmSJU - STL
1 stop7h 10mDelta
Deal found 6/10$219
This Priceline deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/18:44 amSTL - SJU
1 stop7h 02mMultiple Airlines
Thu 9/43:40 amSJU - STL
1 stop10h 37mMultiple Airlines
Deal found 6/9$233
This American Airlines deal was found by Cheapflights users on 6/9. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 8/316:00 amSTL - SJU
1 stop15h 49mAmerican Airlines
Sat 9/64:45 pmSJU - STL
1 stop16h 20mAmerican Airlines
Deal found 6/9$244
This Mytrip deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Mytrip is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/46:36 pmSTL - SJU
2 stops16h 21mSpirit Airlines
Wed 7/93:50 pmSJU - STL
1 stop25h 41mSpirit Airlines
Deal found 6/11$280
This United Airlines deal was found by Cheapflights users on 6/11. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 7/43:20 pmSTL - SJU
1 stop7h 34mUnited Airlines
Tue 7/81:10 amSJU - STL
2 stops12h 17mUnited Airlines
Deal found 6/11$335
This Southwest deal was found by Cheapflights users on 6/10. Clicking the “Pick Dates” button in this card will allow you to select your dates and further customize your flight criteria. From there, click “Find deals”, make sure Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/167:45 amSTL - SJU
2 stops13h 10mSouthwest
Thu 10/235:00 amSJU - STL
1 stop12h 25mSouthwest
Deal found 6/10$342

Cheapflights Fare Finder

Customize your flight search to find flights from St. Louis to San Juan that fit within your specific budget. Explore options based on user searches and filter the results based on your desired price range. Find flights that match your budget for a cost-effective journey. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 12, 2025.
Use the filters below to find and compare flights from St. Louis to San Juan that are best for you.

Fly from

St. Louis

Fly to

San Juan

Route

Depart

Return

Price

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Thu 10/9

2:22 pm-11:54 pm

1 stop8h 32m

San Juan Luis Munoz Marin Intl

Sat 10/11

3:40 am-1:27 pm

1 stop10h 47m

$197

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Tue 12/9

11:51 am-11:17 pm

1 stop9h 26m

San Juan Luis Munoz Marin Intl

Fri 12/12

3:25 pm-8:35 pm

1 stop7h 10m

$219

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Mon 9/1

8:44 am-4:46 pm

1 stop7h 02m

San Juan Luis Munoz Marin Intl

Thu 9/4

3:40 am-1:17 pm

1 stop10h 37m

$233

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 8/31

6:00 am-10:49 pm

1 stop15h 49m

San Juan Luis Munoz Marin Intl

Sat 9/6

4:45 pm-8:05 am

1 stop16h 20m

$244

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Fri 7/25

10:47 am-11:32 am

1 stop23h 45m

San Juan Luis Munoz Marin Intl

Wed 7/30

1:37 am-9:52 am

1 stop9h 15m

$275

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Fri 7/4

3:20 pm-11:54 pm

1 stop7h 34m

San Juan Luis Munoz Marin Intl

Tue 7/8

1:10 am-12:27 pm

2 stops12h 17m

$335

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Thu 10/16

7:45 am-9:55 pm

2 stops13h 10m

San Juan Luis Munoz Marin Intl

Thu 10/23

5:00 am-4:25 pm

1 stop12h 25m

$342

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 7/6

6:36 pm-10:39 am

1 stop15h 03m

$96

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Fri 8/22

3:16 pm-2:50 am

1 stop10h 34m

$99

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 9/6

10:15 am-10:07 pm

1 stop10h 52m

$110

Flights are sorted by cheapest round-trip flights first.

Deals found on 6/12

Showing 1-10 of 14 results
1
2

Best time to book a flight from St. Louis to San Juan

Have a flexible travel schedule? Discover the best time to fly to San Juan from St. Louis with our price prediction graph.
Estimated round-trip price
Rates are based on past data. Find the cheapest month and day to book your flight based on your travel requirements, then search for cheap deals.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to San Juan

How far ahead should I book a flight from St. Louis to San Juan?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to San Juan. Price data was last updated on June 9, 2025.

The price you pay for your flight from St. Louis to San Juan may vary depending on when you book. For the best chance of a lower fare, look to book 71 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.

What is the cheapest month to book a flight from St. Louis to San Juan?

Currently, September is the cheapest month in which you can book a flight from St. Louis to San Juan (average of $254). Flying from St. Louis to San Juan in June is currently the most expensive (average of $339). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

What is the cheapest time of day to fly from STL to SJU?

Find hourly flight availability from St. Louis to San Juan. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated June 12, 2025.

When flying from St. Louis to San Juan, the time of day you fly usually plays a role in the price. Save by searching for a flight in the evening, which can drop the price by up to 53% versus a flight at noon.

What is the cheapest day to fly from St. Louis to San Juan?

Use this chart to determine the cheapest time to fly round-trip from St. Louis to San Juan. Price data was last updated on December 16, 2024.

Travelers seeking maximum savings on their St. Louis to San Juan flight should consider departing on Tuesday evenings when fares are most often at their lowest. Saturday at noon flights should be avoided if possible as fares are typically the most expensive at this time.

Rainfall in San Juan by month

Plan your trip to San Juan by taking into account the average rainfall totals by month.

In terms of precipitation, rainfall in San Juan ranges from 2.2 - 6.1 inches per month. November is typically the wettest month, when rainfall can reach 6.1 in. February is typically the driest time to visit San Juan when rainfall is around 2.2 in.

Temperature in San Juan by month

Plan your trip to San Juan by taking into account the average temperature totals by month.

If weather is an important factor for your trip to San Juan, use this chart to help with planning. For those seeking warmer temperatures, June is the ideal time of year to visit, when temperatures reach an average of 82.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 77.0 F).

Reviews of airlines servicing San Juan

Get insights into the airlines that provide service to San Juan. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to San Juan. Reviews last updated June 12, 2025.
See what other customers who have flown with Southwest, Delta and United Airlines from St. Louis to San Juan have to say. Users can see the overall rating for each airline as well as how each is rated in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,287 reviews

Entertainment

7.6

Comfort

8.0

Food

7.1

Crew

8.6

Boarding

8.2

Overall

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.
Southwest
8.0
Very good
4,287 reviews
Southwest
8.0
Very good
4,287 reviews

Entertainment

7.6

Comfort

8.0

Food

7.1

Crew

8.6

Boarding

8.2

Overall

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.
Delta
8.0
Very good
7,946 reviews
Southwest
8.0
Very good
4,287 reviews

Entertainment

7.6

Comfort

8.0

Food

7.1

Crew

8.6

Boarding

8.2

Overall

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.
United Airlines
7.4
Good
8,790 reviews
Southwest
8.0
Very good
4,287 reviews

Entertainment

7.6

Comfort

8.0

Food

7.1

Crew

8.6

Boarding

8.2

Overall

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,287 reviews

Entertainment

7.6

Comfort

8.0

Food

7.1

Crew

8.6

Boarding

8.2

Overall

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.
Spirit Airlines
6.3
Okay
8,052 reviews
Southwest
8.0
Very good
4,287 reviews

Entertainment

7.6

Comfort

8.0

Food

7.1

Crew

8.6

Boarding

8.2

Overall

8.0

Reviews

1 / 20
8.0
Excellent

John,May 2025

PVD - BNA

It’s southwest so no frills but clean, efficient and got me to my location.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to San Juan. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly from for flights from St. Louis to San Juan?

    Most people fly from Lambert-St Louis (STL) if they book a flight from St. Louis to San Juan. On average, Lambert-St Louis has 0 outbound flights to San Juan per day from 6 airlines. Lambert-St Louis is conveniently located just 12.7 mi from St. Louis’s city center.

  • What are the cheapest airlines flying from St. Louis to San Juan round-trip?

    Our cheapest airline available from St. Louis to San Juan is Frontier. Our recent data shows that you can find tickets from as low as $197 on this airline. Additional options worth looking into are Delta and American Airlines, starting at $219 and $244 round-trip. Frontier is 55% cheaper than the average price of flights available within the next 90 days to this destination.

  • What are the cheapest airlines to fly from St. Louis to San Juan one-way?

    To fly one-way, consider booking your trip with Spirit Airlines, which is currently one of the cheapest options available, starting at $96. Frontier flights start at $99 while deals on Delta start at $110 one-way.

  • What are the cheapest flights from St. Louis to San Juan?

    The cheapest flight price from St. Louis to San Juan is $566. On average you can expect to pay $660. The most popular route, (Lambert-St Louis - San Juan Luis Munoz Marin Intl), can usually be booked for $219.

  • Where are the most common layover locations when flying from St. Louis to San Juan?

    St. Louis to San Juan flights have a layover in Charlotte most often. Orlando sees the next most layovers on St. Louis to San Juan flights.

  • What are some popular things to do or see while on a layover in Charlotte?

    The majority of Charlotte visitors spend their time at Carowind, Mint Museum Uptown, and NASCAR Hall of Fame. Carowind, Mint Museum Uptown, and NASCAR Hall of Fame are located about 8.2 mi, 5.4 mi, and 5.7 mi, respectively from Charlotte Douglas. Travelers in need of a car in Charlotte can rent one for about $48 per day.

  • What are some popular points of interest to see during a layover in Orlando?

    Orlando travelers tend to visit Walt Disney World Resort, Universal Orlando Resort, and International Drive more than any other notable places. Walt Disney World Resort, Universal Orlando Resort, and International Drive are located about 16.2 mi, 10.2 mi, and 9.9 mi, respectively from Orlando. Travelers can book a car rental at Orlando for about $24 per day to make their sightseeing more efficient.

  • Where are the least popular layover locations for St. Louis to San Juan flights?

    Flights departing from St. Louis and landing in San Juan layover in Atlanta least frequently.

  • Can I find deals for flights from St. Louis to San Juan that include hotel bookings?

    Yes. In addition to deals on St. Louis to San Juan flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to San Juan?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to San Juan.

  • Can I find deals for business class flights from St. Louis to San Juan?

    Yes. Cheapflights offers flight deals from St. Louis to San Juan by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

  • What is the cheapest month to book a flight from St. Louis to San Juan?

    Currently, September is the cheapest month in which you can book a flight from St. Louis to San Juan (average of $254). Flying from St. Louis to San Juan in June is currently the most expensive (average of $339). There are several factors that can impact the price of a flight, so comparing airlines, departure airports and flight times can provide users with more options.

See more FAQs

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Alternative routes for St. Louis to San Juan

See prices for flight routes from nearby airports that may be better suited for you.
Kansas City to Luis Munoz Marin Intl flights
St. Louis to Luis Munoz Marin Intl flights
Springfield to Luis Munoz Marin Intl flights
Kansas City to Aguadilla flights
St. Louis to Culebra flights

Top 6 airlines flying from St. Louis to San Juan

Discover the top 6 airlines that operate flights from St. Louis to San Juan. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated June 12, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$140Average$251FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$155Average$290FlexibilityNo cancel feeOn-time65%
United AirlinesCheapest$219Average$385FlexibilityNo cancel feeOn-time69%
DeltaCheapest$244Average$396FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$254Average$495FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$351Average$597FlexibilityNo cancel feeOn-time63%

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