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Cheap flights from St. Louis to San Juan from $103

This is the cheapest one-way flight price found by a momondo user in the last 72 hours by searching for a flight from St. Louis to San Juan departing on 11/18. Fares may change, and may not be available for all flights or travel dates. Click the price to refresh the search for this deal.
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0 bags

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Find the cheapest flights from St. Louis to San Juan (STL-SJU)

Cheap round-trip flights

American Airlines Logo
5:28 am - 11:37 pmSTL-SJU
17h 09m1 stop
American Airlines Logo
1:40 pm - 10:50 pmSJU-STL
10h 10m2 stops
$205American Airlines
Find Deal
dom., sep. 21 - sáb., sep. 27
Delta Logo
1:26 pm - 10:00 pmSTL-SJU
7h 34m1 stop
Delta Logo
7:15 am - 3:55 pmSJU-STL
9h 40m1 stop
$244Delta
Find Deal
sáb., oct. 4 - mar., oct. 7
United Airlines Logo
11:10 am - 9:26 pmSTL-SJU
8h 16m1 stop
United Airlines Logo
2:05 am - 12:15 pmSJU-STL
12h 10m2 stops
$262United Airlines
Find Deal
mar., dic. 9 - vie., dic. 12
Frontier Logo
3:37 pm - 2:54 amSTL-SJU
9h 17m1 stop
Frontier Logo
3:55 am - 10:46 pmSJU-STL
20h 51m1 stop
$269Frontier
Find Deal
jue., nov. 27 - vie., dic. 5
Frontier Logo
5:11 pm - 2:50 amSTL-SJU
7h 39m1 stop
Frontier Logo
11:05 am - 10:46 pmSJU-STL
13h 41m1 stop
$273Frontier
Find Deal
lun., dic. 8 - mar., dic. 9
Delta Logo
6:00 am - 2:15 pmSTL-SJU
6h 15m1 stop
Delta Logo
3:25 pm - 8:35 pmSJU-STL
7h 10m1 stop
$283Delta
Find Deal
mar., dic. 9 - mié., dic. 10
United Airlines Logo
6:35 am - 2:44 pmSTL-SJU
7h 09m1 stop
United Airlines Logo
1:05 am - 12:28 pmSJU-STL
12h 23m2 stops
$295United Airlines
Find Deal
lun., sep. 22 - vie., sep. 26
Southwest Logo
5:25 am - 2:10 pmSTL-SJU
7h 45m1 stop
Southwest Logo
5:00 am - 2:15 pmSJU-STL
10h 15m2 stops
$301Southwest
Find Deal
mar., sep. 16 - mar., sep. 23
American Airlines Logo
5:57 am - 9:55 pmSTL-SJU
13h 58m1 stop
American Airlines Logo
7:20 am - 9:44 pmSJU-STL
16h 24m1 stop
$303American Airlines
Find Deal
mar., feb. 10 - sáb., feb. 21
Southwest Logo
4:55 pm - 12:45 amSTL-SJU
6h 50m1 stop
Southwest Logo
3:35 pm - 10:25 pmSJU-STL
7h 50m1 stop
$318Southwest
Find Deal
vie., oct. 10 - lun., oct. 13

United Airlines flights from St. Louis to San Juan Luis Munoz Marin Intl Airport

Our best United Airlines deals on St. Louis to San Juan Luis Munoz Marin Intl Airport flight tickets
United Airlines
Dec 9
STL11:10 amLambert-St Louis
8h 16m
1 stop
SJU9:26 pmSan Juan Luis Munoz Marin Intl
Dec 12
SJU2:05 amSan Juan Luis Munoz Marin Intl
12h 10m
2 stops
STL12:15 pmLambert-St Louis
$262
Find similar
United Airlines
Sep 22
STL6:35 amLambert-St Louis
7h 09m
1 stop
SJU2:44 pmSan Juan Luis Munoz Marin Intl
Sep 26
SJU1:05 amSan Juan Luis Munoz Marin Intl
12h 23m
2 stops
STL12:28 pmLambert-St Louis
$295
Find similar
United Airlines
Sep 16
STL6:15 amLambert-St Louis
8h 27m
1 stop
SJU3:42 pmSan Juan Luis Munoz Marin Intl
Sep 24
SJU3:56 pmSan Juan Luis Munoz Marin Intl
7h 39m
1 stop
STL10:35 pmLambert-St Louis
$302
Find similar

Spirit Airlines flights from St. Louis to San Juan Luis Munoz Marin Intl Airport

Our best Spirit Airlines deals on St. Louis to San Juan Luis Munoz Marin Intl Airport flight tickets
Spirit Airlines
Aug 24
STL10:37 amLambert-St Louis
10h 11m
1 stop
SJU9:48 pmSan Juan Luis Munoz Marin Intl
Aug 30
SJU2:11 amSan Juan Luis Munoz Marin Intl
12h 21m
2 stops
STL1:32 pmLambert-St Louis
$293
Find similar
Spirit Airlines
Aug 24
STL10:37 amLambert-St Louis
10h 11m
1 stop
SJU9:48 pmSan Juan Luis Munoz Marin Intl
Aug 31
SJU4:12 pmSan Juan Luis Munoz Marin Intl
22h 20m
1 stop
STL1:32 pmLambert-St Louis
$319
Find similar
Spirit Airlines
Aug 28
STL2:30 pmLambert-St Louis
9h 26m
2 stops
SJU12:56 amSan Juan Luis Munoz Marin Intl
Aug 30
SJU2:11 amSan Juan Luis Munoz Marin Intl
12h 21m
2 stops
STL1:32 pmLambert-St Louis
$327
Find similar

momondo Fare Finder

 
Customize your flight search to find flights from St. Louis to San Juan Luis Munoz Marin Intl Airport 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, momondo users made 832,500 searches. Data last updated agosto 18, 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

Fly to

Route

Depart

Return

Price

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

dom. 9/21

5:28 am-11:37 pm

1 stop17h 09m

San Juan Luis Munoz Marin Intl

sáb. 9/27

1:40 pm-10:50 pm

2 stops10h 10m

$205

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

sáb. 10/4

1:26 pm-10:00 pm

1 stop7h 34m

San Juan Luis Munoz Marin Intl

mar. 10/7

7:15 am-3:55 pm

1 stop9h 40m

$244

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 12/9

11:10 am-9:26 pm

1 stop8h 16m

San Juan Luis Munoz Marin Intl

vie. 12/12

2:05 am-12:15 pm

2 stops12h 10m

$262

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

jue. 11/27

3:37 pm-2:54 am

1 stop9h 17m

San Juan Luis Munoz Marin Intl

vie. 12/5

3:55 am-10:46 pm

1 stop20h 51m

$269

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

lun. 12/8

5:11 pm-2:50 am

1 stop7h 39m

San Juan Luis Munoz Marin Intl

mar. 12/9

11:05 am-10:46 pm

1 stop13h 41m

$273

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 12/9

6:00 am-2:15 pm

1 stop6h 15m

San Juan Luis Munoz Marin Intl

mié. 12/10

3:25 pm-8:35 pm

1 stop7h 10m

$283

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

lun. 9/22

6:35 am-2:44 pm

1 stop7h 09m

San Juan Luis Munoz Marin Intl

vie. 9/26

1:05 am-12:28 pm

2 stops12h 23m

$295

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 9/16

5:25 am-2:10 pm

1 stop7h 45m

San Juan Luis Munoz Marin Intl

mar. 9/23

5:00 am-2:15 pm

2 stops10h 15m

$301

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

mar. 2/10

5:57 am-9:55 pm

1 stop13h 58m

San Juan Luis Munoz Marin Intl

sáb. 2/21

7:20 am-9:44 pm

1 stop16h 24m

$303

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

vie. 10/10

4:55 pm-12:45 am

1 stop6h 50m

San Juan Luis Munoz Marin Intl

lun. 10/13

3:35 pm-10:25 pm

1 stop7h 50m

$318

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first
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See travel insights to San Juan from

How to get the cheapest flight ticket from St. Louis to San Juan Luis Munoz Marin Intl Airport

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

What is the cheapest month to fly to San Juan Luis Munoz Marin Intl Airport?

If you aren’t able to travel to San Juan Luis Munoz Marin Intl Airport during the month of September, then flying in April is also cheap. Prices for this month can be found on momondo for an average of $368.

What is the cheapest day to depart on your flight to San Juan Luis Munoz Marin Intl Airport?

On average, the least expensive day to fly to San Juan Luis Munoz Marin Intl Airport from St. Louis is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $404. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Saturday is the most expensive day to depart from St. Louis because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $636.

What is the cheapest time of day to depart on your flight to San Juan Luis Munoz Marin Intl Airport?

The cheapest time of day to fly to San Juan Luis Munoz Marin Intl Airport is in the evening when flights can be purchased for as low as $310. Flights at noon are often more expensive with an average ticket price of $660.

What is the cheapest Lambert-St Louis to San Juan Luis Munoz Marin Intl flight route?

Fly from Lambert-St Louis to San Juan Luis Munoz Marin Intl for the best Lambert-St Louis - San Juan Luis Munoz Marin Intl flight prices

How far in advance should I book a flight to San Juan Luis Munoz Marin Intl Airport?

You are more likely to see cheaper flights to San Juan Luis Munoz Marin Intl Airport from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to San Juan Luis Munoz Marin Intl Airport for around $451 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to San Juan Luis Munoz Marin Intl Airport from St. Louis for as low as $335 on momondo.

What cabin class options are available on Lambert-St Louis to San Juan Luis Munoz Marin Intl flights?

There are 1 cabin classes available to choose from on Lambert-St Louis to San Juan Luis Munoz Marin Intl flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

How have St. Louis to San Juan Luis Munoz Marin Intl Airport flight prices changed over time?

As of August 2025, prices for St. Louis to San Juan Luis Munoz Marin Intl Airport flights are approximately 30% more expensive when compared to flights at the same time last year.

When to book flights from St. Louis to San Juan Luis Munoz Marin Intl Airport

Are you open to changing your travel dates? Check out the ideal times to fly from St. Louis to San Juan Luis Munoz Marin Intl Airport according to our flight data. Find out which month and days have the cheapest flights.
Estimated round-trip price

Cheap St. Louis to San Juan Luis Munoz Marin Intl Airport (STL to SJU) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to San Juan Luis Munoz Marin Intl Airport

Best Price Found

$103

Fastest flight time

6h 15m

Direct flights

Sun
The best one-way flight to San Juan Luis Munoz Marin Intl Airport from St. Louis in the past 72 hours is $103. The best round-trip flight deal from St. Louis to San Juan Luis Munoz Marin Intl Airport found on momondo in the last 72 hours is $205.
The fastest flight from St. Louis to San Juan Luis Munoz Marin Intl Airport takes 6h 15m
Direct flights go from St. Louis to San Juan Luis Munoz Marin Intl Airport on Sunday. The only airline offering direct flights is Southwest.
Search flight deals

  • How far is Lambert-St Louis to San Juan Luis Munoz Marin Intl by plane?

    There are 2011.8 mi between Lambert-St Louis and San Juan Luis Munoz Marin Intl. A reasonable flight in good conditions will take 6h 15m.

  • When did momondo last update prices for flights from Lambert-St Louis Airport to San Juan Luis Munoz Marin Intl Airport?

    Prices for flights from Lambert-St Louis Airport to San Juan Luis Munoz Marin Intl Airport are updated daily.

  • How many operators does momondo search for flights from Lambert-St Louis Airport to San Juan Luis Munoz Marin Intl Airport?

  • How old do you have to be to fly from Lambert-St Louis Airport to San Juan Luis Munoz Marin Intl Airport?

    The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Lambert-St Louis Airport to San Juan Luis Munoz Marin Intl Airport.

  • What documentation or ID do you need to fly to San Juan Luis Munoz Marin Intl Airport?

    The travel and health documents you'll need for your trip to San Juan Luis Munoz Marin Intl Airport may differ based on your itinerary and personal situation. Typically, you should have several documents on hand, such as a national ID card or driver's license and a passport that is valid for six months after your intended arrival at San Juan Luis Munoz Marin Intl Airport. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

  • What is the most popular plane model from St. Louis to San Juan Luis Munoz Marin Intl Airport?

  • What is the most popular airline from St. Louis to San Juan Luis Munoz Marin Intl Airport?

Best airlines flying from St. Louis to San Juan Luis Munoz Marin Intl Airport

Compare and see reviews for airlines that fly from St. Louis to San Juan Luis Munoz Marin Intl Airport with momondo
Airline
Rating
Free Cancellation
Price
FrontierPriceFrom $140Free CancellationRating
5.8
3,212 reviews
Search Frontier flights
Spirit AirlinesPriceFrom $170Free CancellationRating
6.3
8,038 reviews
Search Spirit Airlines flights
DeltaPriceFrom $209Free CancellationRating
8.0
7,981 reviews
Search Delta flights
United AirlinesPriceFrom $219Free CancellationRating
7.4
8,925 reviews
Search United Airlines flights
SouthwestPriceFrom $219Free CancellationRating
8.0
4,246 reviews
Search Southwest flights
American AirlinesPriceFrom $256Free CancellationRating
7.2
10,000 reviews
Search American Airlines flights

Traveling to a place near San Juan?

Book flights to San Juan if you plan to visit one of these locations
Carolina
Fajardo
Dorado
Luquillo
Caguas
Humacao
Rio Grande
Bayamón

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to San Juan?

momondo compares prices from hundreds of airlines and agents so you can find and book the best deal on flights from St. Louis to San Juan. Millions of users trust and use momondo every year so you are in good hands.

Can I find flights from St. Louis to San Juan with flexible booking policies on momondo?

All flight searches from St. Louis to San Juan on momondo can be filtered to show those which offer flexible booking policies.

How can momondo help me find flights from St. Louis to San Juan?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to San Juan from St. Louis.

I’m not ready to book a flight from St. Louis to San Juan right now. Can momondo alert me if prices change?

Yes momondo offers price alerts on flights to San Juan from St. Louis. After performing a search on this page you should be able to see the price alert set up feature. Simply provide a valid email address and momondo will instantly alert you when prices change.

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