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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 3/24. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SJU
feb. 13 — feb. 201
vie. 2/13
vie. 2/20
1 adult, Economy
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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 enero 14, 2026.

Most accurate provider

CheapOair
3 stars

Most trusted provider

CheapOair
3 stars

Round-trip from

$178
(Priceline)

One-way from

$86
(Super.com)

Popular in

December

Cheapest in

September

Average price

$438
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.
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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. 13% potential increase in price ($71 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($16 potential savings vs. average RT price).
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Average for round-trip flights in January 2026
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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 enero 14, 2026.

This Priceline deal was found by Cheapflights users on 1/12. 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. 3/284:51 pm
STL
-
SJU
1 stop16h 06m
Frontier
sáb. 4/411:30 am
SJU
-
STL
1 stop12h 03m
Frontier
Deal found 1/12$176
This CheapOair deal was found by Cheapflights users on 1/12. 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.
sáb. 3/74:51 pm
STL
-
SJU
1 stop15h 36m
Frontier
sáb. 3/149:41 pm
SJU
-
STL
1 stop10h 21m
Frontier
Deal found 1/12$177
This Frontier deal was found by Cheapflights users on 1/12. 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.
mar. 2/173:49 pm
STL
-
SJU
1 stop8h 59m
Frontier
mar. 2/245:25 pm
SJU
-
STL
1 stop7h 02m
Frontier
Deal found 1/12$178
This CheapOair deal was found by Cheapflights users on 1/12. 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.
lun. 2/25:42 pm
STL
-
SJU
1 stop28h 17m
Frontier
sáb. 2/78:00 am
SJU
-
STL
1 stop17h 33m
Frontier
Deal found 1/12$179
This CheapOair deal was found by Cheapflights users on 1/12. 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.
lun. 3/23:49 pm
STL
-
SJU
1 stop9h 04m
Frontier
mar. 3/103:08 am
SJU
-
STL
1 stop28h 54m
Frontier
Deal found 1/12$180
This Frontier deal was found by Cheapflights users on 1/13. 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.
lun. 3/23:49 pm
STL
-
SJU
1 stop9h 04m
Frontier
mié. 3/45:25 pm
SJU
-
STL
1 stop7h 02m
Frontier
Deal found 1/13$182
This CheapOair deal was found by Cheapflights users on 1/13. 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.
jue. 2/55:42 pm
STL
-
SJU
1 stop14h 42m
Frontier
mar. 2/105:25 pm
SJU
-
STL
1 stop7h 02m
Frontier
Deal found 1/13$183
This Priceline deal was found by Cheapflights users on 1/12. 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.
mié. 1/215:42 pm
STL
-
SJU
1 stop28h 17m
Frontier
mié. 1/288:00 am
SJU
-
STL
1 stop17h 33m
Frontier
Deal found 1/12$195
This Frontier deal was found by Cheapflights users on 1/13. 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.
mar. 3/33:49 pm
STL
-
SJU
1 stop9h 04m
Frontier
jue. 3/55:25 pm
SJU
-
STL
1 stop8h 34m
Frontier
Deal found 1/13$197
This CheapOair deal was found by Cheapflights users on 1/13. 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.
mar. 3/33:49 pm
STL
-
SJU
1 stop9h 04m
Frontier
dom. 3/83:08 am
SJU
-
STL
1 stop21h 11m
Frontier
Deal found 1/13$198
This Frontier deal was found by Cheapflights users on 1/13. 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.
mar. 2/243:49 pm
STL
-
SJU
1 stop6h 54m
Frontier
mar. 3/311:07 am
SJU
-
STL
1 stop13h 20m
Frontier
Deal found 1/13$199

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 enero 14, 2026.
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

mié. 1/21

5:42 pm-11:59 pm

1 stop28h 17m

San Juan Luis Munoz Marin Intl

mié. 1/28

8:00 am-11:33 pm

1 stop17h 33m

$204

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 3/3

6:00 am-4:36 pm

1 stop8h 36m

San Juan Luis Munoz Marin Intl

jue. 3/5

2:05 am-12:27 pm

2 stops12h 22m

$267

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

lun. 3/2

9:55 am-9:00 pm

1 stop9h 05m

San Juan Luis Munoz Marin Intl

jue. 3/5

2:05 am-12:27 pm

2 stops12h 22m

$282

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 2/3

9:57 am-10:22 pm

2 stops10h 25m

San Juan Luis Munoz Marin Intl

sáb. 2/7

2:05 am-12:29 pm

2 stops12h 24m

$314

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

lun. 3/2

7:41 am-12:36 am

2 stops14h 55m

San Juan Luis Munoz Marin Intl

mié. 3/4

2:05 am-2:42 pm

2 stops14h 37m

$316

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

lun. 3/2

7:41 am-12:36 am

2 stops14h 55m

San Juan Luis Munoz Marin Intl

mié. 3/4

4:52 pm-10:59 pm

1 stop8h 07m

$336

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

sáb. 1/31

9:57 am-9:00 pm

1 stop9h 03m

San Juan Luis Munoz Marin Intl

sáb. 2/7

7:45 am-3:39 pm

1 stop9h 54m

$356

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

vie. 2/20

4:15 pm-1:35 am

2 stops7h 20m

San Juan Luis Munoz Marin Intl

jue. 2/26

6:30 am-5:15 pm

2 stops12h 45m

$366

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

lun. 3/2

2:35 pm-12:40 am

2 stops8h 05m

San Juan Luis Munoz Marin Intl

mar. 3/10

5:15 am-8:00 pm

2 stops15h 45m

$378

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 3/3

7:41 am-10:22 pm

2 stops12h 41m

San Juan Luis Munoz Marin Intl

mar. 3/3

2:05 am-2:29 pm

2 stops14h 24m

$401

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/12

Showing 1-10 of 23 results
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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 January.
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 January 9, 2026.

Booking 24 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 enero 14, 2026.

When flying from St. Louis to San Juan Luis Munoz Marin Intl Airport, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.

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 enero 14, 2026.
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
4,258 reviews

Entertainment

7.5

Comfort

8.0

Crew

8.6

Boarding

8.1

Overall

8.0

Food

7.0

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
4,258 reviews
Southwest
8.0
Very good
4,258 reviews

Entertainment

7.5

Comfort

8.0

Crew

8.6

Boarding

8.1

Overall

8.0

Food

7.0

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
8,048 reviews
Southwest
8.0
Very good
4,258 reviews

Entertainment

7.5

Comfort

8.0

Crew

8.6

Boarding

8.1

Overall

8.0

Food

7.0

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
9,163 reviews
Southwest
8.0
Very good
4,258 reviews

Entertainment

7.5

Comfort

8.0

Crew

8.6

Boarding

8.1

Overall

8.0

Food

7.0

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
11,129 reviews
Southwest
8.0
Very good
4,258 reviews

Entertainment

7.5

Comfort

8.0

Crew

8.6

Boarding

8.1

Overall

8.0

Food

7.0

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
5.7
Fair
3,056 reviews
Southwest
8.0
Very good
4,258 reviews

Entertainment

7.5

Comfort

8.0

Crew

8.6

Boarding

8.1

Overall

8.0

Food

7.0

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 Frontier and United Airlines fly from St. Louis to San Juan Luis Munoz Marin Intl Airport in about 8h 36m. The time it takes to get you to your destination can typically vary by up to 19h 41m. 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 ($146), and Delta ($180) 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.

  • 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
Fajardo
Dorado
Luquillo
Rio Grande
Humacao
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 enero 14, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$140Average$306FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$170Average$334FlexibilityNo cancel feeOn-time65%
DeltaCheapest$205Average$399FlexibilityNo cancel feeOn-timeN/A
SouthwestCheapest$219Average$569FlexibilityNo cancel feeOn-time63%
United AirlinesCheapest$225Average$390FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$255Average$528FlexibilityNo cancel feeOn-time71%

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