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Luis Munoz Marin Intl

$86+ 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 1/31. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SJU
Jan 22 — Jan 291
Thu 1/22
Thu 1/29
1 adult, Economy
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Find cheap flights from St. Louis to Luis Munoz Marin Intl with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

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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 75 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

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 December 23, 2025.

This CheapOair deal was found by Cheapflights users on 12/22. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/304:27 pmSTL - SJU
1 stop26h 00mFrontier
Tue 1/63:55 amSJU - STL
1 stop20h 38mFrontier
Deal found 12/22$268
This CheapOair deal was found by Cheapflights users on 12/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/304:27 pmSTL - SJU
1 stop8h 23mFrontier
Thu 1/110:08 amSJU - STL
1 stop24h 04mFrontier
Deal found 12/21$346
This CheapOair deal was found by Cheapflights users on 12/21. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/2510:42 amSTL - SJU
1 stop11h 55mFrontier
Thu 1/110:08 amSJU - STL
1 stop24h 04mFrontier
Deal found 12/21$356
This Priceline deal was found by Cheapflights users on 12/21. 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 12/2510:42 amSTL - SJU
1 stop11h 55mFrontier
Sat 12/273:55 amSJU - STL
1 stop20h 38mFrontier
Deal found 12/21$389
This CheapOair deal was found by Cheapflights users on 12/22. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 12/304:27 pmSTL - SJU
1 stop14h 56mFrontier
Tue 1/67:18 pmSJU - STL
1 stop29h 15mFrontier
Deal found 12/22$440
This Expedia deal was found by Cheapflights users on 12/21. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 12/244:27 pmSTL - SJU
1 stop8h 23mFrontier
Sun 12/2810:33 pmSJU - STL
1 stop11h 39mFrontier
Deal found 12/21$459
This CheapOair deal was found by Cheapflights users on 12/22. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/2510:42 amSTL - SJU
1 stop11h 55mFrontier
Tue 12/309:37 pmSJU - STL
1 stop26h 56mFrontier
Deal found 12/22$475
This Priceline deal was found by Cheapflights users on 12/22. 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.
Tue 12/304:27 pmSTL - SJU
1 stop26h 00mFrontier
Fri 1/29:37 pmSJU - STL
1 stop26h 56mFrontier
Deal found 12/22$484
This CheapOair deal was found by Cheapflights users on 12/23. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 12/294:27 pmSTL - SJU
1 stop8h 23mFrontier
Mon 1/59:37 pmSJU - STL
1 stop26h 56mFrontier
Deal found 12/23$523

Find 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 December 23, 2025.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$171
(Frontier)

One-way from

$86
(Priceline)

Popular in

December

Cheapest in

September

Average price

$618
Provider with most accurate pricing for Lambert-St Louis-San Juan Luis Munoz Marin Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Lambert-St Louis-San Juan Luis Munoz Marin Intl flights.
Search Deals
From Lambert-St Louis to San Juan Luis Munoz Marin Intl
Search Deals
One-way flight from Lambert-St Louis to San Juan Luis Munoz Marin Intl
Search Deals
Highest demand for flights based on searches. 15% potential increase in price ($78 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($16 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

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 December 23, 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

Tue 3/10

7:05 am-7:39 pm

1 stop11h 34m

San Juan Luis Munoz Marin Intl

Thu 3/12

1:30 am-8:55 am

1 stop8h 25m

$225

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 1/24

3:11 pm-6:11 am

2 stops13h 00m

San Juan Luis Munoz Marin Intl

Wed 1/28

3:46 pm-10:00 pm

1 stop8h 14m

$225

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 1/18

9:59 am-8:58 pm

1 stop8h 59m

San Juan Luis Munoz Marin Intl

Sat 1/24

6:15 am-11:54 am

1 stop7h 39m

$225

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 5/3

11:43 am-8:06 pm

1 stop7h 23m

San Juan Luis Munoz Marin Intl

Wed 5/6

6:15 am-12:06 pm

1 stop6h 51m

$225

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 1/25

6:30 am-3:40 pm

1 stop7h 10m

San Juan Luis Munoz Marin Intl

Thu 1/29

2:05 am-10:41 am

1 stop10h 36m

$225

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Tue 3/17

10:12 am-8:18 pm

1 stop9h 06m

San Juan Luis Munoz Marin Intl

Wed 4/1

5:30 pm-11:58 pm

1 stop7h 28m

$225

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Wed 1/21

9:57 am-10:22 pm

2 stops10h 25m

San Juan Luis Munoz Marin Intl

Tue 1/27

7:45 am-3:52 pm

1 stop10h 07m

$225

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Wed 1/21

1:00 pm-11:45 pm

1 stop8h 45m

San Juan Luis Munoz Marin Intl

Wed 1/28

6:27 pm-11:37 pm

1 stop7h 10m

$225

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 1/11

5:11 pm-11:16 am

1 stop16h 05m

San Juan Luis Munoz Marin Intl

Fri 1/16

4:35 pm-6:51 am

1 stop16h 16m

$235

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 2/7

12:12 pm-11:59 pm

1 stop9h 47m

$90

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/21

Showing 1-10 of 19 results
1
2

Compare providers for flights from St. Louis to Luis Munoz Marin Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from St. Louis to Luis Munoz Marin Intl in December.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars
AranGrantPrice Accuracy2 starsTrust Score*3 stars
PricelinePrice Accuracy1 starTrust Score*3 stars
CheapTicketsDealPrice Accuracy3 starsTrust Score*3 stars
CheapflightsfaresPrice Accuracy3 starsTrust Score*2 stars
CheapOairPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on St. Louis-San Juan Luis Munoz Marin Intl Airport flights, users find the pricing of CheapOair to be most consistent on Cheapflights vs. CheapOair Users can find the same prices on St. Louis-San Juan Luis Munoz Marin Intl Airport flight deals on Cheapflights vs. CheapOair >95% of the time. Price accuracy is based on data collected from St. Louis-San Juan Luis Munoz Marin Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on St. Louis-San Juan Luis Munoz Marin Intl Airport flights, Cheapflights users trust CheapOair the most. CheapOair has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for St. Louis-San Juan Luis Munoz Marin Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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 December 19, 2025.

Booking 75 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, May is the cheapest month in which you can book a flight from St. Louis to San Juan Luis Munoz Marin Intl Airport (average of $140). Flying from St. Louis to San Juan Luis Munoz Marin Intl Airport in June is currently the most expensive (average of $249). 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 December 23, 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 52% 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 December 23, 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
4,253 reviews

Entertainment

7.5

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Southwest
8.0
Very good
4,253 reviews
Southwest
8.0
Very good
4,253 reviews

Entertainment

7.5

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Delta
7.9
Good
8,014 reviews
Southwest
8.0
Very good
4,253 reviews

Entertainment

7.5

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
United Airlines
7.4
Good
9,105 reviews
Southwest
8.0
Very good
4,253 reviews

Entertainment

7.5

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
American Airlines
7.2
Good
11,054 reviews
Southwest
8.0
Very good
4,253 reviews

Entertainment

7.5

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am
Frontier
5.8
Fair
3,075 reviews
Southwest
8.0
Very good
4,253 reviews

Entertainment

7.5

Overall

8.0

Boarding

8.1

Food

7.0

Crew

8.6

Comfort

8.0

Reviews

1 / 20
2.0
Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am

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 American Airlines, United Airlines, and Delta fly from St. Louis to San Juan Luis Munoz Marin Intl Airport in about 8h 59m. The time it takes to get you to your destination can typically vary by up to 4h 01m. 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 ($137), Spirit Airlines ($146), and Delta ($197) offers the cheapest pricing from St. Louis to San Juan Luis Munoz Marin Intl Airport. Frontier is 69% 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 Luis Munoz Marin Intl Airport one-way?

    $64 is the cheapest one-way deal found within the past few days, from Frontier. You may also be able to find cheap deals on Southwest and United Airlines, with prices starting from $110 and $112, respectively.

  • 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, May is the cheapest month in which you can book a flight from St. Louis to San Juan Luis Munoz Marin Intl Airport (average of $140). Flying from St. Louis to San Juan Luis Munoz Marin Intl Airport in June is currently the most expensive (average of $249). 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
Humacao
Luquillo
Bayamón

Browse thousands of different options on Cheapflights for your next trip

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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 December 23, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$140Average$304FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$170Average$334FlexibilityNo cancel feeOn-time65%
DeltaCheapest$205Average$396FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$219Average$577FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$225Average$392FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$263Average$528FlexibilityNo cancel feeOn-time71%

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