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$65+ 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 5/19. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SJU
Feb 25 — Mar 41
Tue 2/25
Tue 3/4
1 adult, Economy
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The best prices from Lambert-St Louis to San Juan are usually found in April or January, booked 90 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 February 20, 2025.

Round-trip from

$158
(Mytrip)

One-way from

$65
(Frontier)

Popular in

July

Cheapest in

April

Average price

$440
From Lambert-St Louis to San Juan
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One-way flight from Lambert-St Louis to San Juan
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($47 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($12 potential savings vs. average RT price).
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Average for round-trip flights in February 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 February 20, 2025.

This Mytrip deal was found by Cheapflights users on 2/20. 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.
Sat 5/35:47 pmSTL - SJU
1 stop8h 04mFrontier
Sat 5/109:30 pmSJU - STL
1 stop27h 36mFrontier
Deal found 2/20$158
This CheapOair deal was found by Cheapflights users on 2/19. 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 5/135:47 pmSTL - SJU
1 stop8h 04mMultiple Airlines
Mon 5/194:46 pmSJU - STL
1 stop26h 46mMultiple Airlines
Deal found 2/19$165
This CheapOair deal was found by Cheapflights users on 2/19. 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 5/137:37 pmSTL - SJU
2 stops28h 34mSpirit Airlines
Mon 5/194:46 pmSJU - STL
1 stop26h 46mSpirit Airlines
Deal found 2/19$185
This United Airlines deal was found by Cheapflights users on 2/20. 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.
Sat 5/33:43 pmSTL - SJU
1 stop7h 11mUnited Airlines
Tue 5/61:05 amSJU - STL
2 stops14h 42mUnited Airlines
Deal found 2/20$265
This Southwest deal was found by Cheapflights users on 2/20. 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.
Sat 5/31:25 pmSTL - SJU
Nonstop4h 25mSouthwest
Sat 5/104:00 pmSJU - STL
Nonstop5h 00mSouthwest
Deal found 2/20$285
This Delta deal was found by Cheapflights users on 2/20. 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.
Wed 5/2810:10 amSTL - SJU
1 stop8h 24mDelta
Tue 6/32:04 pmSJU - STL
1 stop7h 29mDelta
Deal found 2/20$314
This American Airlines deal was found by Cheapflights users on 2/20. 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.
Fri 5/96:00 amSTL - SJU
2 stops9h 36mAmerican Airlines
Thu 5/151:10 pmSJU - STL
1 stop9h 17mAmerican Airlines
Deal found 2/20$321

Find flights from St. Louis to San Juan within your budget

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 February 20, 2025.

Fly from

St. Louis

Fly to

San Juan

Route

Depart

Return

Price

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 5/3

5:47 pm-2:51 am

1 stop8h 04m

San Juan Luis Munoz Marin Intl

Sat 5/10

9:30 pm-12:06 am

1 stop27h 36m

$158

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Tue 5/13

5:47 pm-2:51 am

1 stop8h 04m

San Juan Luis Munoz Marin Intl

Mon 5/19

4:46 pm-6:32 pm

1 stop26h 46m

$165

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Tue 5/13

7:37 pm-1:11 am

2 stops28h 34m

San Juan Luis Munoz Marin Intl

Mon 5/19

4:46 pm-6:32 pm

1 stop26h 46m

$185

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 5/3

3:43 pm-11:54 pm

1 stop7h 11m

San Juan Luis Munoz Marin Intl

Tue 5/6

1:05 am-2:47 pm

2 stops14h 42m

$265

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 5/3

1:25 pm-6:50 pm

Nonstop4h 25m

San Juan Luis Munoz Marin Intl

Sat 5/10

4:00 pm-8:00 pm

Nonstop5h 00m

$285

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Wed 5/28

10:10 am-7:34 pm

1 stop8h 24m

San Juan Luis Munoz Marin Intl

Tue 6/3

2:04 pm-8:33 pm

1 stop7h 29m

$314

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Fri 5/9

6:00 am-4:36 pm

2 stops9h 36m

San Juan Luis Munoz Marin Intl

Thu 5/15

1:10 pm-9:27 pm

1 stop9h 17m

$321

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Mon 5/19

5:47 pm-2:51 am

1 stop8h 04m

$65

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Tue 6/3

7:37 pm-3:41 pm

1 stop19h 04m

$124

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Tue 3/18

1:06 pm-11:07 pm

1 stop9h 01m

$133

Flights are sorted by cheapest round-trip flights first.

Deals found on 2/20

Showing 1-10 of 14 results
1
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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.

Travel insights for flights from St. Louis to San Juan

Get recent, data-driven insights about flights from St. Louis to San Juan including ideal travel times, pricing trends, and more.

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 February 14, 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 90 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 March is currently the most expensive (average of $363). 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 February 20, 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 afternoon, which can drop the price by up to 45% versus a flight in the morning.

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 February 18, 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 mornings 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 February 20, 2025.
See what other customers who have flown with Southwest, Alaska Airlines and Delta 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
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Southwest
8.1
Very good
4,411 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Alaska Airlines
8.0
Very good
9,692 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

Delta
8.0
Very good
8,220 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

United Airlines
7.4
Good
8,766 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

American Airlines
7.2
Good
10,000 reviews
Southwest
8.1
Very good
4,411 reviews

Crew

8.7

Food

7.1

Comfort

8.1

Overall

8.1

Boarding

8.2

Entertainment

7.6

Reviews

1 / 20

2.0
Mediocre

Anonymous,Feb 2025

MCO - STL

Cancelled at last minute, SWA unable to assist in formulating alternate plans. Wound up renting a car and driving 13 hours to beat bad weather forecast at home. Not SWA’s fault that there was significant bad weather across the country.

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 $158 on this airline. Additional options worth looking into are Spirit Airlines and United Airlines, starting at $185 and $265 round-trip. Frontier is 64% 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 Frontier, which is currently one of the cheapest options available, starting at $65. Spirit Airlines flights start at $119 while deals on Delta start at $133 one-way.

  • 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 North Carolina Blumenthal Performing Arts Center. Carowind, Mint Museum Uptown, and North Carolina Blumenthal Performing Arts Center are located about 8.2 mi, 5.4 mi, and 5.8 mi, respectively from Charlotte Douglas. Travelers in need of a car in Charlotte can rent one for about $44 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 $27 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 March is currently the most expensive (average of $363). 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 February 20, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$140Average$287FlexibilityNo cancel feeOn-time62%
Spirit AirlinesCheapest$172Average$310FlexibilityNo cancel feeOn-time65%
DeltaCheapest$254Average$434FlexibilityNo cancel feeOn-timeN/A
United AirlinesCheapest$264Average$447FlexibilityNo cancel feeOn-time69%
American AirlinesCheapest$277Average$511FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$392Average$587FlexibilityNo cancel feeOn-time63%
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