What day of the week experiences the fewest flight delays on this route?

Saturday is statistically the day of the week which experiences the fewest number of delays on this flight route. Monday has historically seen more delays on average compared to the rest of the week.

Which airline has the best punctuality record on St. Louis to Puerto Rico flights?

According to our data, Southwest have had the least number of delays on this route over the last 12 months; with about 33% of their flights experiencing any sort of delay.

What is the most punctual flight time for St. Louis to Puerto Rico flights?

Generally, flights departing in the morning tend to experience fewer delays. Flights in the early afternoon have, in the past, seen delays more frequently in comparison.

What airlines fly to Puerto Rico?

American Airlines, Frontier and Southwest are the top three most popular airlines that fly to Puerto Rico from St. Louis according to our data. American Airlines is the first choice among our users, with 42% of people opting to fly with this airline when traveling to Puerto Rico. Keep in mind that there are 6 different airlines that fly to Puerto Rico on a routine basis, so you have a few additional options to choose from.

What is the cheapest airline that flies from Lambert-St Louis to Puerto Rico?

Frontier and Delta are the most popular carriers operating from Lambert-St Louis to Puerto Rico

How often are flights from St. Louis to Puerto Rico delayed?

Historically, on average around 34% of flights between St. Louis and Puerto Rico have experienced a delay on any given week. The average delay length over the past 12 months has been 91 minutes.

When did momondo last update prices for flights from Lambert-St Louis Airport to Puerto Rico?

Prices for flights from Lambert-St Louis Airport to Puerto Rico are refreshed on a daily basis.

How many operators does momondo search for flights from Lambert-St Louis Airport to Puerto Rico?

The number of operators available for flights from Lambert-St Louis Airport to Puerto Rico is 6 as of May 2026.

How old do you have to be to fly from Lambert-St Louis Airport to Puerto Rico?

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 Puerto Rico.

What documentation or ID do you need to fly to Puerto Rico?

The travel and health documents you'll need for your trip to Puerto Rico 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 Puerto Rico. It is always advisable to seek advice from your airline or a trusted third party, such as IATA.

$159 Cheap Flights from St. Louis to Puerto Rico in 2026

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Find the cheapest flights from St. Louis to Puerto Rico

Round-trip

One-way

Last minute

Cheap round-trip flights

Enter your travel dates to find the best prices.

4:52 pm - 12:23 am

STL

SJU

30h 31m

2 stops

5:15 pm - 8:52 am

SJU

STL

16h 37m

1 stop

$326Frontier

Mon, Aug 17 - Fri, Aug 21

4:52 pm - 2:34 pm

STL

SJU

44h 42m

2 stops

5:15 pm - 8:57 am

SJU

STL

16h 42m

1 stop

$327Frontier

Mon, Jul 6 - Thu, Aug 6

6:00 am - 1:42 pm

STL

SJU

6h 42m

1 stop

6:48 am - 2:33 pm

SJU

STL

8h 45m

1 stop

$336Delta

Mon, Aug 17 - Thu, Aug 20

4:52 pm - 2:34 pm

STL

SJU

44h 42m

2 stops

5:15 pm - 8:57 am

SJU

STL

16h 42m

1 stop

$340Frontier

Fri, Aug 7 - Thu, Aug 13

6:03 am - 6:24 pm

STL

SJU

11h 21m

2 stops

3:28 pm - 11:54 pm

SJU

STL

9h 26m

2 stops

$341American Airlines

Mon, Aug 17 - Thu, Aug 27

4:52 pm - 4:42 pm

STL

SJU

22h 50m

2 stops

5:15 pm - 8:52 am

SJU

STL

16h 37m

1 stop

$343Frontier

Sat, Aug 15 - Fri, Aug 21

6:33 pm - 2:34 pm

STL

SJU

43h 01m

2 stops

5:15 pm - 8:57 am

SJU

STL

16h 42m

1 stop

$344Frontier

Sun, Jul 5 - Thu, Aug 6

5:00 am - 12:48 pm

STL

SJU

6h 48m

1 stop

1:38 pm - 11:59 pm

SJU

STL

11h 21m

2 stops

$346American Airlines

Sun, Aug 16 - Thu, Aug 20

6:31 pm - 2:29 pm

STL

SJU

42h 58m

2 stops

5:15 pm - 5:37 pm

SJU

STL

25h 22m

1 stop

$349Frontier

Thu, Jul 2 - Wed, Jul 8

6:33 pm - 2:16 pm

STL

SJU

18h 43m

1 stop

5:15 pm - 5:37 pm

SJU

STL

25h 22m

1 stop

$354Frontier

Sun, Aug 9 - Wed, Aug 12

Delta flights from St. Louis to Puerto Rico

Our best Delta deals on St. Louis to Puerto Rico flight tickets

Delta

Aug 21

STL6:00 amLambert-St Louis

9h 37m

1 stop

SJU4:37 pmSan Juan Luis Munoz Marin Intl

Aug 25

SJU6:48 amSan Juan Luis Munoz Marin Intl

10h 29m

1 stop

STL4:17 pmLambert-St Louis

$336

Delta

Sep 18

STL6:00 amLambert-St Louis

9h 31m

1 stop

SJU4:31 pmSan Juan Luis Munoz Marin Intl

Sep 22

SJU5:41 pmSan Juan Luis Munoz Marin Intl

6h 56m

1 stop

STL11:37 pmLambert-St Louis

$406

American Airlines flights from St. Louis to Puerto Rico

Our best American Airlines deals on St. Louis to Puerto Rico flight tickets

American Airlines

Sep 2

STL6:03 amLambert-St Louis

11h 21m

2 stops

SJU6:24 pmSan Juan Luis Munoz Marin Intl

Sep 9

SJU6:30 amSan Juan Luis Munoz Marin Intl

11h 41m

2 stops

STL5:11 pmLambert-St Louis

$341

American Airlines

Aug 21

STL6:03 amLambert-St Louis

15h 21m

1 stop

SJU10:24 pmSan Juan Luis Munoz Marin Intl

Aug 25

SJU1:38 pmSan Juan Luis Munoz Marin Intl

10h 02m

2 stops

STL10:40 pmLambert-St Louis

$346

American Airlines

Sep 2

STL6:00 amLambert-St Louis

11h 24m

2 stops

SJU6:24 pmSan Juan Luis Munoz Marin Intl

Sep 9

SJU6:30 amSan Juan Luis Munoz Marin Intl

7h 52m

1 stop

STL1:22 pmLambert-St Louis

$351

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Mon 8/17

4:52 pm-12:23 am

2 stops30h 31m

San Juan Luis Munoz Marin Intl

Fri 8/21

5:15 pm-8:52 am

1 stop16h 37m

$326

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Mon 7/6

4:52 pm-2:34 pm

2 stops44h 42m

San Juan Luis Munoz Marin Intl

Thu 8/6

5:15 pm-8:57 am

1 stop16h 42m

$327

Quickest round-trip

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Mon 8/17

6:00 am-1:42 pm

1 stop6h 42m

San Juan Luis Munoz Marin Intl

Thu 8/20

6:48 am-2:33 pm

1 stop8h 45m

$336

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Fri 8/7

4:52 pm-2:34 pm

2 stops44h 42m

San Juan Luis Munoz Marin Intl

Thu 8/13

5:15 pm-8:57 am

1 stop16h 42m

$340

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Mon 8/17

6:03 am-6:24 pm

2 stops11h 21m

San Juan Luis Munoz Marin Intl

Thu 8/27

3:28 pm-11:54 pm

2 stops9h 26m

$341

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 8/15

4:52 pm-4:42 pm

2 stops22h 50m

San Juan Luis Munoz Marin Intl

Fri 8/21

5:15 pm-8:52 am

1 stop16h 37m

$343

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 7/5

6:33 pm-2:34 pm

2 stops43h 01m

San Juan Luis Munoz Marin Intl

Thu 8/6

5:15 pm-8:57 am

1 stop16h 42m

$344

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 8/16

5:00 am-12:48 pm

1 stop6h 48m

San Juan Luis Munoz Marin Intl

Thu 8/20

1:38 pm-11:59 pm

2 stops11h 21m

$346

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Thu 7/2

6:31 pm-2:29 pm

2 stops42h 58m

San Juan Luis Munoz Marin Intl

Wed 7/8

5:15 pm-5:37 pm

1 stop25h 22m

$349

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 8/9

6:33 pm-2:16 pm

1 stop18h 43m

San Juan Luis Munoz Marin Intl

Wed 8/12

5:15 pm-5:37 pm

1 stop25h 22m

$354

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 resultsSorted by cheapest first

How to get the cheapest flight ticket from St. Louis to Puerto Rico

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

Prices

Airlines

Delays

What is the cheapest month to fly to Puerto Rico?

If you don’t want to visit Puerto Rico in July, then you should wait until November to fly from St. Louis, when ticket prices are also cheap, with an average price of $113.

What is the cheapest Lambert-St Louis to Puerto Rico flight route?

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

How far in advance should I book a flight from St. Louis to Puerto Rico?

You are more likely to see cheaper flights to Puerto Rico from St. Louis when booking weeks ahead of your departure date. In general, you can expect to find flights to Puerto Rico for around $422 when searching weeks out. However, flight prices might be lower outside of this timeframe. For example, people recently found flights to Puerto Rico from St. Louis for as low as $346 on momondo.

What cabin class options are available on St. Louis to Puerto Rico flights?

There is only 1 cabin class available to choose from on St. Louis to Puerto Rico flights. Cabin price and availability will vary by airline so perform a search above to find the right deals for you.

Cheap St. Louis to Puerto Rico flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Puerto Rico

Fastest flight time	4h 20m
Direct flights	Sun
Airports in Puerto Rico	20 airports

The fastest flight from St. Louis to Puerto Rico takes 4h 20m

Direct flights go from St. Louis to Puerto Rico on Sunday. There are no airlines offering direct flights.

There are 20 airports in Puerto Rico. From St. Louis there are direct flights to San Juan Luis Munoz Marin Intl (SJU).

Search flight deals

Frequently asked questions about flying from St. Louis to Puerto Rico

When did momondo last update prices for flights from Lambert-St Louis Airport to Puerto Rico?
Prices for flights from Lambert-St Louis Airport to Puerto Rico are refreshed on a daily basis.
How many operators does momondo search for flights from Lambert-St Louis Airport to Puerto Rico?
The number of operators available for flights from Lambert-St Louis Airport to Puerto Rico is 6 as of May 2026.
How old do you have to be to fly from Lambert-St Louis Airport to Puerto Rico?
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 Puerto Rico.
What documentation or ID do you need to fly to Puerto Rico?
The travel and health documents you'll need for your trip to Puerto Rico 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 Puerto Rico. 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 Puerto Rico?
Based on momondo bookings for this flight route, the most popular plane model on flight routes from St. Louis to Puerto Rico is Boeing 737-800 Passenger/BBJ2 (winglets) (50.00% of total bookings). The next most popular plane models are Boeing 737 MAX 8 (25.00%) and Boeing 737-700 Passenger/BBJ1 (winglets) (25.00%).

Best airlines flying from St. Louis to Puerto Rico

Compare and see reviews for airlines that fly from St. Louis to Puerto Rico with momondo

Airline	Rating	Free Cancellation	Price
Frontier	PriceFrom $138	Free Cancellation	Rating 5.6 2,945 reviews	Search Frontier flights
Delta	PriceFrom $205	Free Cancellation	Rating 7.9 8,452 reviews	Search Delta flights
Southwest	PriceFrom $220	Free Cancellation	Rating 7.9 4,282 reviews	Search Southwest flights
United Airlines	PriceFrom $225	Free Cancellation	Rating 7.4 9,748 reviews	Search United Airlines flights
American Airlines	PriceFrom $226	Free Cancellation	Rating 7.1 11,642 reviews	Search American Airlines flights
Spirit Airlines	PriceFrom $233	Free Cancellation	Rating 6.2 8,609 reviews	Search Spirit Airlines flights

Why use momondo?

Why should I use momondo to find a flight deal from St. Louis to Puerto Rico?

To find the flight that best suits your needs, momondo gathers a range of flights from a large pool of different airlines and agents; you can then use our insights and filters to find and book the right flight to Puerto Rico from St. Louis.

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

Yes. momondo allows you to filter the results for St. Louis to Puerto Rico flights to just show those with flexible booking policies.

How can momondo help me find flights from St. Louis to Puerto Rico?

momondo offers useful filters to help you find the right flight. Choose specific flight times, airports or even what payment method you prefer. We have numerous options to help you book your ideal flight from St. Louis to Puerto Rico.

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

Yes. momondo can track prices for St. Louis to Puerto Rico flights and alert you when they change. Perform a search to set up the price alert. All that is required is a valid email address.

An easier way to manage your Puerto Rico trip

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Popular cities in Puerto Rico

Flights to San Juanfrom $182

Flights to Aguadillafrom $212

Flights to Poncefrom $178

Flights to Culebrafrom $499

Flights to Mayagüezfrom $467

Cheap flights from St. Louis to Puerto Rico from $159

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 Puerto Rico departing on 8/11. 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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Delta flights from St. Louis to Puerto Rico

Our best Delta deals on St. Louis to Puerto Rico flight tickets

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Our best American Airlines deals on St. Louis to Puerto Rico flight tickets

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How to get the cheapest flight ticket from St. Louis to Puerto Rico

What is the cheapest month to fly to Puerto Rico?

What is the cheapest Lambert-St Louis to Puerto Rico flight route?

How far in advance should I book a flight from St. Louis to Puerto Rico?

What cabin class options are available on St. Louis to Puerto Rico flights?

What is the cheapest airline that flies from Lambert-St Louis to Puerto Rico?

What airlines fly to Puerto Rico?

How often are flights from St. Louis to Puerto Rico delayed?

What is the most punctual flight time for St. Louis to Puerto Rico flights?

What day of the week experiences the fewest flight delays on this route?

Which airline has the best punctuality record on St. Louis to Puerto Rico flights?

Cheap St. Louis to Puerto Rico flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from St. Louis to Puerto Rico

Fastest flight time

Direct flights

Airports in Puerto Rico

Frequently asked questions about flying from St. Louis to Puerto Rico

Best airlines flying from St. Louis to Puerto Rico

Compare and see reviews for airlines that fly from St. Louis to Puerto Rico with momondo

Why use momondo?

An easier way to manage your Puerto Rico trip

We make it super easy to schedule, organize and travel with friends or family. Trips is free — and available to use no matter where you book.

Get notified when prices go down

Daily price changes in your inbox - only with Price Alerts.

Find better results for your trip to Puerto Rico

Popular cities in Puerto Rico

Popular flights according to clicks in the last 7 days on momondo

St. Louis flight routes

According to popular flight searches on momondo this year

Puerto Rico flight routes

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Fly your favorite airline to Puerto Rico

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List of cabin classes available on flights landing in Puerto Rico. Availability may vary depending on flight origin and airline.

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