$87+ 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 2/18. Fares are subject to change and may not be available on all flights or dates of travel.
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Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.Cheap flight deals from St. Louis to San Juan
Cheapest flights from St. Louis to San JuanExplore 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 January 21, 2026.
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 January 21, 2026.
This Frontier deal was found by Cheapflights users on 1/20. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This CheapOair deal was found by Cheapflights users on 1/19. 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.
This CheapOair deal was found by Cheapflights users on 1/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This CheapOair deal was found by Cheapflights users on 1/21. 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.
This CheapOair deal was found by Cheapflights users on 1/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This CheapOair deal was found by Cheapflights users on 1/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This CheapOair deal was found by Cheapflights users on 1/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This Kiwi.com deal was found by Cheapflights users on 1/20. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This CheapOair deal was found by Cheapflights users on 1/20. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
This CheapOair deal was found by Cheapflights users on 1/21. 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.
This Kiwi.com deal was found by Cheapflights users on 1/19. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Find 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 January 21, 2026.
Round-trip from | $178 (Frontier) |
|---|---|
One-way from | $87 (Priceline) |
Popular in | December |
Cheapest in | September |
Average price | $438 |
Cheapflights Fare Finder
Use the filters below to find and compare flights from St. Louis to San Juan that are best for you.
Fly from
Fly to
Route
Depart
Return
Price
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Thu 4/9
11:21 am-12:52 am
1 stop12h 31m
San Juan Luis Munoz Marin Intl
Mon 4/13
9:10 pm-11:19 pm
1 stop27h 09m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Fri 2/27
3:49 pm-2:53 am
1 stop9h 04m
San Juan Luis Munoz Marin Intl
Tue 3/3
5:25 pm-10:27 pm
1 stop7h 02m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Fri 2/27
8:22 pm-7:43 pm
2 stops21h 21m
San Juan Luis Munoz Marin Intl
Tue 3/3
8:05 pm-10:27 pm
1 stop28h 22m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Tue 2/10
3:49 pm-12:43 am
1 stop6h 54m
San Juan Luis Munoz Marin Intl
Fri 2/20
3:53 am-8:56 am
1 stop7h 03m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Sat 3/7
4:51 pm-3:58 am
1 stop9h 07m
San Juan Luis Munoz Marin Intl
Thu 3/12
12:07 pm-7:22 am
1 stop20h 15m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Wed 4/15
6:00 am-6:06 pm
2 stops11h 06m
San Juan Luis Munoz Marin Intl
Wed 4/22
6:56 pm-10:16 am
1 stop16h 20m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Mon 3/2
7:41 am-12:36 am
2 stops14h 55m
San Juan Luis Munoz Marin Intl
Wed 3/4
3:46 pm-10:14 pm
1 stop8h 28m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Wed 3/18
11:32 am-1:58 am
2 stops13h 26m
San Juan Luis Munoz Marin Intl
Tue 3/24
7:00 am-11:19 pm
1 stop17h 19m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Mon 3/16
8:10 pm-8:53 am
1 stop11h 43m
San Juan Luis Munoz Marin Intl
Mon 3/23
9:58 pm-10:32 am
2 stops13h 34m
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Tue 3/17
8:06 pm-10:03 pm
2 stops24h 57m
San Juan Luis Munoz Marin Intl
Tue 3/24
7:00 am-11:19 pm
1 stop17h 19m
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.
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 January 16, 2026.
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 75 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, May is the cheapest month in which you can book a flight from St. Louis to San Juan (average of $142). Flying from St. Louis to San Juan in June is currently the most expensive (average of $251). 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 January 21, 2026.
When flying from St. Louis to San Juan, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
How much does it cost to fly round-trip from St. Louis to San Juan?
How often are flights from St. Louis to San Juan delayed?
About 20% of weekly flights between St. Louis and San Juan have experienced delays in the past year, with the average delay time being 85 minutes.
What is the most punctual flight time for St. Louis to San Juan flights?
Historically, flights departing in the early afternoon are less likely to be delayed, whereas flights leaving in the morning tend to experience delays more often.
What day of the week experiences the fewest flight delays on this route?
Saturday tends to have the lowest number of delays on this route, whereas Monday has historically faced a higher average of delays compared to other days of the week.
Which airline has the best punctuality record on St. Louis to San Juan flights?
Over the last year, Southwest have had the lowest number of delays on this route, with just 18% of flights being delayed.
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 January 21, 2026.
Peruse reviews from past customers who have flown with Southwest, Delta, and United Airlines from St. Louis to San Juan to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Boarding
Entertainment
Crew
Overall
Comfort
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Crew
Overall
Comfort
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Crew
Overall
Comfort
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Crew
Overall
Comfort
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Crew
Overall
Comfort
Food
Reviews
Thomas,Dec 2025
SEA - DEN
Boarding
Entertainment
Crew
Overall
Comfort
Food
Reviews
Thomas,Dec 2025
SEA - DEN
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.
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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.
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 January 21, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$133 | Average$277 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$146 | Average$329 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$180 | Average$392 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$219 | Average$567 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$225 | Average$382 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$234 | Average$523 | FlexibilityNo cancel fee | On-time71% |