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St. Louis

$90+ Cheap flights from San Juan to St. Louis (STL)

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 1/12. Fares are subject to change and may not be available on all flights or dates of travel.
SJU — STL
Jan 3 — Jan 101
Sat 1/3
Sat 1/10
1 adult, Economy
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Find cheap flights from San Juan to St. Louis with Cheapflights

1. Tell us where you want to go

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Cheapflights Tip: The best prices from San Juan to Lambert-St Louis are usually found in January or September, booked 65 days in advance, depart on a Tuesday or Thursday and return on a Wednesday

Cheap flight deals from San Juan to St. Louis

Cheapest flights from San Juan to St. Louis
Explore the most affordable flight options available from San Juan to St. Louis. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 4, 2025.

This Frontier deal was found by Cheapflights users on 12/3. 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.
Thu 12/115:09 pmSJU - STL
1 stop7h 24mFrontier
Mon 12/153:30 pmSTL - SJU
1 stop9h 20mFrontier
Deal found 12/3$252
This Mytrip deal was found by Cheapflights users on 12/2. 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.
Thu 12/1111:05 amSJU - STL
1 stop13h 28mFrontier
Sun 12/143:30 pmSTL - SJU
1 stop16h 25mFrontier
Deal found 12/2$278
This Frontier deal was found by Cheapflights users on 12/2. 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.
Thu 12/255:09 pmSJU - STL
1 stop7h 24mFrontier
Mon 12/294:27 pmSTL - SJU
1 stop8h 23mFrontier
Deal found 12/2$300
This Booking.com deal was found by Cheapflights users on 12/4. 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 Booking.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/189:37 pmSJU - STL
1 stop26h 56mFrontier
Mon 12/224:27 pmSTL - SJU
1 stop14h 56mFrontier
Deal found 12/4$301
This Kiwi.com deal was found by Cheapflights users on 12/3. 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.
Thu 12/115:00 pmSJU - STL
1 stop17h 59mMultiple Airlines
Mon 12/159:54 amSTL - SJU
2 stops12h 51mMultiple Airlines
Deal found 12/3$306
This Kiwi.com deal was found by Cheapflights users on 12/2. 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.
Thu 12/1111:05 amSJU - STL
1 stop13h 28mMultiple Airlines
Sun 12/143:30 pmSTL - SJU
2 stops19h 02mMultiple Airlines
Deal found 12/2$307
This Frontier deal was found by Cheapflights users on 12/4. 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.
Thu 12/45:09 pmSJU - STL
1 stop7h 24mFrontier
Mon 12/83:30 pmSTL - SJU
1 stop9h 20mFrontier
Deal found 12/4$314
This Priceline deal was found by Cheapflights users on 12/3. 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.
Sat 12/209:58 pmSJU - STL
1 stop26h 35mFrontier
Mon 12/294:27 pmSTL - SJU
1 stop8h 23mFrontier
Deal found 12/3$320

Find flight deals from San Juan to St. Louis

Discover tips and strategies to find the most affordable flight options for your journey from San Juan (PR1) to St. Louis (STL). 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 4, 2025.

Round-trip from

$180
(Frontier)

One-way from

$90
(Priceline)

Popular in

June

Cheapest in

January

Average price

$371
From San Juan to Lambert-St Louis
Search Deals
One-way flight from San Juan to Lambert-St Louis
Search Deals
Highest demand for flights based on searches. 19% potential increase in price ($94 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($11 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
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Cheapflights Fare Finder

 
Customize your flight search to find flights from San Juan to St. Louis 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 4, 2025.
Use the filters below to find and compare flights from San Juan to St. Louis that are best for you.

Fly from

San Juan

Fly to

St. Louis

Route

Depart

Return

Price

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Thu 1/22

4:36 pm-11:33 pm

1 stop8h 57m

Lambert-St Louis

Mon 1/26

10:16 am-6:40 pm

1 stop6h 24m

$201

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Fri 1/23

4:36 pm-11:33 pm

1 stop8h 57m

Lambert-St Louis

Sat 1/31

12:12 pm-11:59 pm

1 stop9h 47m

$215

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Fri 2/13

6:00 am-1:20 pm

1 stop9h 20m

Lambert-St Louis

Mon 2/16

2:45 pm-1:05 am

1 stop8h 20m

$225

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Wed 1/21

6:27 pm-11:37 pm

1 stop7h 10m

Lambert-St Louis

Sun 2/1

6:00 am-5:17 pm

1 stop9h 17m

$225

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Fri 1/23

7:30 am-2:49 pm

1 stop9h 19m

Lambert-St Louis

Tue 1/27

1:00 pm-8:58 pm

1 stop5h 58m

$225

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Thu 1/15

6:27 pm-11:39 pm

1 stop7h 12m

Lambert-St Louis

Mon 1/19

6:00 am-2:31 pm

1 stop6h 31m

$225

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Wed 1/21

6:27 pm-11:37 pm

1 stop7h 10m

Lambert-St Louis

Mon 1/26

7:10 am-5:17 pm

1 stop8h 07m

$225

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Fri 2/13

5:14 pm-11:02 pm

1 stop7h 48m

Lambert-St Louis

Mon 2/16

5:14 am-3:12 pm

1 stop7h 58m

$250

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Thu 2/12

7:00 am-5:27 pm

1 stop12h 27m

Lambert-St Louis

Mon 2/16

6:00 am-11:44 pm

1 stop15h 44m

$257

San JuanSt. Louis

SJU - STL

SJUSTL

San Juan Luis Munoz Marin Intl

Thu 1/22

8:05 pm-10:23 am

1 stop16h 18m

Lambert-St Louis

Mon 1/26

8:22 pm-3:35 pm

2 stops17h 13m

$264

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/4

Showing 1-10 of 21 results
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Best time to book a flight from San Juan to St. Louis

Have a flexible travel schedule? Discover the best time to fly to St. Louis from San Juan 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 San Juan to St. Louis

How far ahead should I book a flight from San Juan to St. Louis?

Use this chart to determine the optimal time to book a round-trip flight from San Juan to St. Louis. Price data was last updated on November 28, 2025.

Booking 65 days in advance of your planned departure date is, on average, the best time to get cheap flights from San Juan to St. Louis. 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 San Juan to St. Louis?

Currently, January is the cheapest month in which you can book a flight from San Juan to St. Louis (average of $128). Flying from San Juan to St. Louis in August is currently the most expensive (average of $253). 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 SJU to STL?

Find hourly flight availability from San Juan to St. Louis. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated December 4, 2025.

One of the essential ways to save on airfare from San Juan to St. Louis is to remain as flexible as possible. Flights that are in the afternoon tend to be the most expensive. A flight in the evening could potentially save you up to 54% on airfare.

How much does it cost to fly round-trip from San Juan to St. Louis?

Reviews of airlines servicing St. Louis

Get insights into the airlines that provide service to St. Louis. 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 St. Louis. Reviews last updated December 4, 2025.
See what other customers who have flown with Southwest, Delta, and American Airlines from San Juan to St. Louis have to say. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,252 reviews

Comfort

8.0

Overall

8.0

Crew

8.6

Boarding

8.1

Food

7.0

Entertainment

7.5

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
4,252 reviews
Southwest
8.0
Very good
4,252 reviews

Comfort

8.0

Overall

8.0

Crew

8.6

Boarding

8.1

Food

7.0

Entertainment

7.5

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
8,011 reviews
Southwest
8.0
Very good
4,252 reviews

Comfort

8.0

Overall

8.0

Crew

8.6

Boarding

8.1

Food

7.0

Entertainment

7.5

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
11,043 reviews
Southwest
8.0
Very good
4,252 reviews

Comfort

8.0

Overall

8.0

Crew

8.6

Boarding

8.1

Food

7.0

Entertainment

7.5

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
3,092 reviews
Southwest
8.0
Very good
4,252 reviews

Comfort

8.0

Overall

8.0

Crew

8.6

Boarding

8.1

Food

7.0

Entertainment

7.5

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 San Juan to St. Louis. 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 into for flights to St. Louis from San Juan?

    Located just 12.7 mi from the city center, Lambert-St Louis is the airport most travelers will use when flying to St. Louis from San Juan. Booking flights from San Juan to Lambert-St Louis (STL) should be relatively easy as there are 0 daily inbound flights from San Juan from 4 different airlines.

  • How long is the flight from San Juan to St. Louis?

    Airlines like Frontier, Southwest, and Delta fly from San Juan to St. Louis in about 7h 10m. The time it takes to get you to your destination can typically vary by up to 2h 10m. Airlines will cover a distance of 2024 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from San Juan to St. Louis round-trip?

    Our cheapest airline available from San Juan to St. Louis is Frontier. Our recent data shows that you can find tickets from as low as $84 on this airline. Additional options worth looking into are Delta and American Airlines, starting at $170 and $254 round-trip. These flights start at 78% lower than the current average price 3 months from now.

  • What are the cheapest airlines to fly from San Juan to St. Louis one-way?

    For one-way options, check prices for Frontier. According to our data, you can fly for as low as $83. Users have also found prices from $104 and $108 on Delta and Southwest, respectively.

  • Can I find deals for flights from San Juan to St. Louis that include hotel bookings?

    Yes. In addition to deals on San Juan to St. Louis flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from San Juan to St. Louis?

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

  • Can I find deals for business class flights from San Juan to St. Louis?

    Yes. Cheapflights offers flight deals from San Juan to St. Louis 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 San Juan to St. Louis?

    Currently, January is the cheapest month in which you can book a flight from San Juan to St. Louis (average of $128). Flying from San Juan to St. Louis in August is currently the most expensive (average of $253). 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 St. Louis?

Book flights to St. Louis if you plan to visit one of these locations
Edwardsville
O'Fallon
Fairview Heights
Maryland Heights
Collinsville
Swansea
Eureka
Glencoe
St. Peters
Chesterfield
Alton
Farmington
Festus

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Alternative routes for San Juan to St. Louis

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

Top 4 airlines flying from San Juan to St. Louis

Discover the top 4 airlines that operate flights from San Juan to St. Louis. 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 4, 2025.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$128Average$261FlexibilityNo cancel feeOn-time62%
DeltaCheapest$205Average$375FlexibilityNo cancel feeOn-timeN/A
American AirlinesCheapest$254Average$400FlexibilityNo cancel feeOn-time71%
SouthwestCheapest$342Average$610FlexibilityNo cancel feeOn-time63%

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