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Luis Munoz Marin Intl

$113+ Cheap flights from St. Louis (STL) to Luis Munoz Marin Intl (SJU)

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 10/25. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SJU
oct. 17 — oct. 241
vie. 10/17
vie. 10/24
1 adult, Economy
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Cheapflights Tip: The best prices from Lambert-St Louis to San Juan Luis Munoz Marin Intl are usually found in September or April, booked 23 days in advance, depart on a Wednesday or Tuesday and return on a Tuesday

Cheap flight deals from St. Louis to Luis Munoz Marin Intl

Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to Luis Munoz Marin Intl (SJU). 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 septiembre 17, 2025.

Round-trip from

$225
(American Airlines)

One-way from

$113
(Delta)

Popular in

December

Cheapest in

September

Average price

$291
From Lambert-St Louis to San Juan Luis Munoz Marin Intl
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One-way flight from Lambert-St Louis to San Juan Luis Munoz Marin Intl
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Highest demand for flights based on searches. 10% potential increase in price ($51 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($15 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Find flight deals from St. Louis to Luis Munoz Marin Intl

Cheapest flights from St. Louis to Luis Munoz Marin Intl
Explore the most affordable flight options available from St. Louis to Luis Munoz Marin Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on septiembre 17, 2025.

This American Airlines deal was found by Cheapflights users on 9/16. 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.
sáb. 10/1810:23 amSTL - SJU
1 stop11h 42mAmerican Airlines
mié. 10/225:30 amSJU - STL
1 stop15h 44mAmerican Airlines
Deal found 9/16$225
This United Airlines deal was found by Cheapflights users on 9/17. 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.
mar. 12/911:10 amSTL - SJU
1 stop8h 16mUnited Airlines
jue. 12/112:05 amSJU - STL
2 stops12h 10mUnited Airlines
Deal found 9/17$248
This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
jue. 11/273:14 pmSTL - SJU
1 stop7h 52mFrontier
vie. 12/511:05 amSJU - STL
1 stop13h 41mFrontier
Deal found 9/16$268
This Delta deal was found by Cheapflights users on 9/16. 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.
mar. 12/911:40 amSTL - SJU
1 stop9h 30mDelta
vie. 12/123:20 pmSJU - STL
1 stop7h 26mDelta
Deal found 9/16$269
This Frontier deal was found by Cheapflights users on 9/17. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 11/84:33 pmSTL - SJU
1 stop8h 21mFrontier
jue. 11/133:59 amSJU - STL
1 stop8h 21mFrontier
Deal found 9/17$276
This Priceline deal was found by Cheapflights users on 9/16. 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.
vie. 10/106:05 pmSTL - SJU
1 stop7h 25mFrontier
jue. 10/163:40 amSJU - STL
1 stop14h 30mFrontier
Deal found 9/16$290
This Frontier deal was found by Cheapflights users on 9/17. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 11/84:33 pmSTL - SJU
1 stop8h 21mFrontier
dom. 11/1610:39 pmSJU - STL
1 stop13h 01mFrontier
Deal found 9/17$294
This Priceline deal was found by Cheapflights users on 9/16. 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.
vie. 11/72:12 pmSTL - SJU
1 stop19h 07mFrontier
dom. 11/1612:29 pmSJU - STL
1 stop23h 11mFrontier
Deal found 9/16$304
This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 10/257:52 pmSTL - SJU
2 stops15h 09mFrontier
jue. 10/303:04 amSJU - STL
1 stop11h 13mFrontier
Deal found 9/16$313
This Priceline deal was found by Cheapflights users on 9/16. 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.
sáb. 11/17:15 pmSTL - SJU
1 stop15h 41mMultiple Airlines
jue. 11/63:59 amSJU - STL
1 stop11h 18mMultiple Airlines
Deal found 9/16$314
This United Airlines deal was found by Cheapflights users on 9/17. 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.
mar. 11/410:00 amSTL - SJU
1 stop9h 00mUnited Airlines
vie. 11/148:10 amSJU - STL
1 stop8h 15mUnited Airlines
Deal found 9/17$315

Cheapflights Fare Finder

 
Customize your flight search to find flights from St. Louis to Luis Munoz Marin Intl 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 septiembre 17, 2025.
Use the filters below to find and compare flights from St. Louis to San Juan Luis Munoz Marin Intl Airport that are best for you.

Fly from

St. Louis

Fly to

Luis Munoz Marin Intl

Route

Depart

Return

Price

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 11/4

10:00 am-9:00 pm

1 stop9h 00m

San Juan Luis Munoz Marin Intl

vie. 11/14

8:10 am-2:25 pm

1 stop8h 15m

$315

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

sáb. 10/18

9:20 am-11:57 pm

2 stops13h 37m

San Juan Luis Munoz Marin Intl

mar. 10/21

1:05 am-10:49 am

2 stops10h 44m

$334

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

lun. 11/10

11:44 am-11:13 pm

1 stop9h 29m

San Juan Luis Munoz Marin Intl

vie. 11/14

3:20 pm-8:46 pm

1 stop7h 26m

$355

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 10/14

6:15 am-3:42 pm

1 stop8h 27m

San Juan Luis Munoz Marin Intl

mar. 10/14

1:05 am-10:48 am

1 stop10h 43m

$424

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

sáb. 11/1

6:43 pm-9:00 pm

1 stop25h 17m

San Juan Luis Munoz Marin Intl

vie. 1/30

2:05 am-2:30 pm

2 stops14h 25m

$429

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 12/9

10:00 am-12:36 am

2 stops12h 36m

San Juan Luis Munoz Marin Intl

jue. 12/11

2:05 am-2:23 pm

2 stops14h 18m

$452

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mié. 10/15

6:15 am-8:38 pm

1 stop13h 23m

San Juan Luis Munoz Marin Intl

mar. 10/28

1:05 am-11:04 am

1 stop10h 59m

$465

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

sáb. 10/25

6:00 am-2:11 pm

1 stop7h 11m

$113

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 1/13

11:20 am-12:36 am

2 stops11h 16m

$113

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mié. 11/26

3:20 pm-1:40 am

1 stop8h 20m

$113

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/16

Showing 1-10 of 17 results
1
2

Best time to book a flight from St. Louis to Luis Munoz Marin Intl

Have a flexible travel schedule? Discover the best time to fly to Luis Munoz Marin Intl 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 Luis Munoz Marin Intl Airport

How far ahead should I book a flight from St. Louis to San Juan Luis Munoz Marin Intl Airport?

Use this chart to determine the optimal time to book a round-trip flight from St. Louis to Luis Munoz Marin Intl. Price data was last updated on September 12, 2025.

Booking 23 days in advance of your planned departure date is, on average, the best time to get cheap flights from St. Louis to San Juan Luis Munoz Marin Intl Airport. The general trend is that the closer you book to the departure date, the more expensive your flight will be.

What is the cheapest month to book a flight from St. Louis to San Juan Luis Munoz Marin Intl Airport?

Currently, September is the cheapest month in which you can book a flight from St. Louis to San Juan Luis Munoz Marin Intl Airport (average of $254). Flying from St. Louis to San Juan Luis Munoz Marin Intl Airport 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 Luis Munoz Marin Intl. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated septiembre 17, 2025.

When flying from St. Louis to San Juan Luis Munoz Marin Intl Airport, 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 Luis Munoz Marin Intl Airport?

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

Travelers seeking maximum savings on their St. Louis to San Juan Luis Munoz Marin Intl Airport 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.

How much does it cost to fly round-trip from St. Louis to San Juan Luis Munoz Marin Intl Airport?

Reviews of airlines servicing Luis Munoz Marin Intl

Get insights into the airlines that provide service to Luis Munoz Marin Intl. 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 Luis Munoz Marin Intl. Reviews last updated septiembre 17, 2025.
Read through reviews of airlines operating flights from St. Louis to San Juan Luis Munoz Marin Intl Airport, such as Southwest, Delta, and United Airlines. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,242 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Delta
8.0
Very good
7,961 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
United Airlines
7.4
Good
8,926 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
American Airlines
7.2
Good
10,000 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Frontier
5.8
Fair
3,173 reviews
Southwest
8.0
Very good
4,242 reviews

Comfort

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Entertainment

7.5

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Luis Munoz Marin Intl. 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 Luis Munoz Marin Intl?

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

  • How long is the flight from St. Louis to San Juan Luis Munoz Marin Intl Airport?

    Airlines like United Airlines and Delta fly from St. Louis to San Juan Luis Munoz Marin Intl Airport in about 9h. The time it takes to get you to your destination can typically vary by up to 29m. St. Louis and San Juan Luis Munoz Marin Intl Airport are separated by a distance of 2024 mi. When browsing for deals, the options you’ll see will be for both nonstop flights and flights with stops.

  • What are the cheapest airlines flying from St. Louis to San Juan Luis Munoz Marin Intl Airport round-trip?

    According to our current data, Frontier ($140), Spirit Airlines ($170), and Delta ($209) offers the cheapest pricing from St. Louis to San Juan Luis Munoz Marin Intl Airport. Frontier is 68% cheaper than the average price of flights available within the next 90 days to this destination.

  • Can I find deals for flights from St. Louis to Luis Munoz Marin Intl that include hotel bookings?

    Yes. In addition to deals on St. Louis to Luis Munoz Marin Intl flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from St. Louis to Luis Munoz Marin Intl?

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

  • Can I find deals for business class flights from St. Louis to Luis Munoz Marin Intl?

    Yes. Cheapflights offers flight deals from St. Louis to Luis Munoz Marin Intl 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 Luis Munoz Marin Intl Airport?

    Currently, September is the cheapest month in which you can book a flight from St. Louis to San Juan Luis Munoz Marin Intl Airport (average of $254). Flying from St. Louis to San Juan Luis Munoz Marin Intl Airport 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

Traveling to a place near San Juan Luis Munoz Marin Intl Airport?

Book flights to San Juan Luis Munoz Marin Intl Airport if you plan to visit one of these locations
Dorado
Fajardo
Rio Grande
Luquillo
Humacao

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Alternative routes for St. Louis to Luis Munoz Marin Intl

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

Top 6 airlines flying from St. Louis to Luis Munoz Marin Intl

Discover the top 6 airlines that operate flights from St. Louis to Luis Munoz Marin Intl. 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 septiembre 17, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$140Average$270FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$170Average$329FlexibilityNo cancel feeOn-time65%
DeltaCheapest$209Average$378FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$219Average$379FlexibilityNo cancel feeOn-time69%
SouthwestCheapest$219Average$594FlexibilityNo cancel feeOn-time63%
American AirlinesCheapest$255Average$524FlexibilityNo cancel feeOn-time71%

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