$168 Find Cheap Flights from St. Louis to Puerto Rico

This is the cheapest one-way flight price found by a KAYAK user in the last 72 hours by searching for a flight from St. Louis to Puerto Rico departing on 8/25. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
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Book Cheap St. Louis to Puerto Rico Plane Tickets

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from St. Louis to Puerto Rico that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from St. Louis to Puerto Rico

Sun, Sep 27 - Mon, Sep 28
Southwest Logo
3:30 pm - 12:30 am
STL
-
SJU
8h 00m
1 stop
Southwest Logo
11:35 am - 10:25 pm
SJU
-
STL
11h 50m
1 stop
$331Southwest
Mon, Sep 21 - Tue, Sep 29
Delta Logo
6:00 am - 1:16 pm
STL
-
SJU
6h 16m
1 stop
Delta Logo
5:41 pm - 11:36 pm
SJU
-
STL
6h 55m
1 stop
$336Delta
Wed, Sep 2 - Wed, Sep 9
American Airlines Logo
5:59 am - 6:34 pm
STL
-
SJU
11h 35m
2 stops
American Airlines Logo
6:27 am - 9:49 pm
SJU
-
STL
16h 22m
1 stop
$341American Airlines
Sun, Sep 27 - Mon, Sep 28
Southwest Logo
3:30 pm - 12:30 am
STL
-
SJU
8h 00m
1 stop
Southwest Logo
11:35 am - 7:55 pm
SJU
-
STL
9h 20m
2 stops
$368Southwest
Thu, Sep 3 - Thu, Sep 10
Southwest Logo
3:15 pm - 11:50 pm
STL
-
SJU
7h 35m
2 stops
Southwest Logo
6:00 am - 12:00 pm
SJU
-
STL
7h 00m
1 stop
$373Southwest
Wed, Jul 1 - Wed, Jul 8
Frontier Logo
4:17 pm - 2:09 am
STL
-
SJU
8h 52m
1 stop
Frontier Logo
12:13 pm - 11:59 pm
SJU
-
STL
12h 46m
1 stop
$376Frontier
Sat, Jul 4 - Sat, Jul 11
United Airlines Logo
9:20 am - 8:34 pm
STL
-
SJU
10h 14m
1 stop
United Airlines Logo
7:40 am - 3:46 pm
SJU
-
STL
9h 06m
1 stop
$380United Airlines
Sat, Jul 4 - Sat, Jul 11
United Airlines Logo
5:33 pm - 5:29 am
STL
-
SJU
10h 56m
2 stops
United Airlines Logo
7:40 am - 3:46 pm
SJU
-
STL
9h 06m
1 stop
$390United Airlines
Wed, Jul 1 - Mon, Jul 6
Frontier Logo
4:17 pm - 2:09 am
STL
-
SJU
8h 52m
1 stop
Frontier Logo
12:21 pm - 11:59 pm
SJU
-
STL
12h 38m
1 stop
$396Frontier
Fri, Sep 4 - Tue, Sep 8
Southwest Logo
10:10 am - 8:05 pm
STL
-
SJU
8h 55m
2 stops
Southwest Logo
1:20 pm - 7:55 pm
SJU
-
STL
7h 35m
1 stop
$401Southwest
Booking Insights

KAYAK's insights & trends for St. Louis to Puerto Rico flights

Get data-powered insights and trends into flights from St. Louis to Puerto Rico to help you find the cheapest flights, the best time to fly and much more.

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

Data is based on round-trip flight searches on KAYAK over the past month.

The cheapest ticket to Puerto Rico from St. Louis found in the last 3 days was to San Juan, at $496 round-trip. The most popular route is from St. Louis (STL) to San Juan Luis Munoz Marin Intl Airport (SJU), and the cheapest round-trip airline ticket found on this route in the last 3 days was $496.

What is the cheapest time of day to fly to Puerto Rico?

The average price for all round-trip flights from St. Louis to Puerto Rico depending on the time of departure, clicked by users on KAYAK in the last 2 weeks.

The cheapest time of day to fly to Puerto Rico is generally in the morning, when round-trip flights cost $616 on average. The most expensive time of day to fly to Puerto Rico is generally in the morning, which is peak travel time and where the average cost of a ticket is $616.

What is the cheapest month to fly from St. Louis to Puerto Rico?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from St. Louis to Puerto Rico, removes the top 0.1% to account for outliers, and then takes the median of all values for each month.

The cheapest month for flights from St. Louis to Puerto Rico is July, when tickets cost $104 (return) on average. On the other hand, the most expensive months are August and April, when the average cost of round-trip tickets is $219 and $193 respectively.

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

To calculate weekly average prices, KAYAK takes all prices for each week before departure over the last year for round-trip flights from St. Louis to Puerto Rico, removes the top 0.1% to account for outliers, and then takes the average of all the values for each week.

To get a below average price on the flight from St. Louis to Puerto Rico, you should book around 1 week before departure. For the absolute cheapest price, our data suggests you should book 14 weeks before departure.

Good to know

Low seasonSeptember
Cheapest flight$168
Best time to beat the crowds with an average 47% drop in price.
Most popular time to fly and prices are also 4% lower on average.
Flight from St. Louis to San Juan

FAQs - booking Puerto Rico flights

  • From St. Louis, can I fly to the South Coast of Puerto Rico?

    Yes. You can book a flight through KAYAK from STL to the city Ponce, which is located on the southern coast of Puerto Rico. You will be landing at the Mercedita International Airport (PSE). Spirit is one carrier that offers a flight from STL to PSE with one stop, usually in Orlando. Airlines such as Spirit, Cape Air, and JetBlue offer flights from STL to PSE with two stops. Layover cities often include Orlando, Baltimore, Nashville, and other cities.

  • Where can I go in Puerto Rico for a remote tropical vacation?

    You can fly from St. Louis to the Isla Day Culebra, a small island that is part of Puerto Rico but located to the east of the main island. When you fly to this small island, you will be landing at the Aeropuerto Benjamín Rivera Noriega (CPX). Frontier, Spirit, Cape Air, Silver Airways, and United are among the airlines that offer two- or three-stop flights from STL to CPX. Layover destinations include Washington DC, Dallas, Orlando, and others.

  • What is the San Juan Airport like?

    The San Juan Airport on the northern coast of Puerto Rico is the busiest airport in the Caribbean. This four-terminal airport includes a hotel at the airport, exclusive lounges you can access by paying at the door, shops and restaurants that usually close at night, a currency exchange, public transportation, rental cars, and more.

  • Does STL have private facilities for nursing mothers?

    Yes. STL offers lactation suites throughout the airport at Gates A10, C9, and E33. Each lactation suite is a clean, calm, quiet space where a nursing mom can breastfeed in private or where she can go to pump. Each suite features comfortable seating, a table, an ottoman, a bench, a sink, and an electrical outlet.

  • How does KAYAK find such low prices on flights from St. Louis to Puerto Rico?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from St. Louis to Puerto Rico.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from St. Louis to Puerto Rico?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from St. Louis to Puerto Rico is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from St. Louis to Puerto Rico?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly from St. Louis to Puerto Rico with an airline and back with another airline.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from St. Louis to Puerto Rico?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying from St. Louis to Puerto Rico up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Top tips for finding cheap flights to Puerto Rico

  • The St. Louis Lambert International Airport (STL) is a hub for Air Choice One and Cape Air. When you book your flight through KAYAK for St. Louis to Puerto Rico, you will have many options of destination, airline, flight time, and price.
  • When you fly from STL to San Juan, the capital of Puerto Rico, you'll be landing on the northeast of the island at the Luis Muñoz Marín International Airport (SJU). Airlines such as Spirit, Frontier, Delta, and United are among the carriers that offer one-stop flights from STL to SJU. Common layover cities include Atlanta, Orlando, and Charlotte. United and American are among the airlines that offer flights from STL to SJU with two stops.
  • If you're flying from STL to Aguadilla, the beach town in the northwest of Puerto Rico, you'll be landing at Rafael Hernández Marín International Airport (BQN). Frontier and Spirit are among the airlines that offer one- and two-stop flights from STL to BQN, with layovers in cities such as Orlando, Tampa, Las Vegas, and Fort Lauderdale.
  • As you wait for your flight to Puerto Rico at the St. Louis International Airport, you can enjoy the live music of a piano player in the terminal. STL decided to have the piano player as part of an arts and culture initiative at the airport, a program designed to delight travelers and enhance their experience.
  • The St. Louis Airport has two interfaith chapels that welcome all. These quiet spaces are meant for reflection, meditation, prayer, or simply for relaxation. These chapels are open 24/7. One chapel is located on the lower level of Terminal 1 and the other is near Gate E40.

Reviews of the top 5 airlines serving from St. Louis to Puerto Rico

 
Need help choosing which airline to fly with from St. Louis to Puerto Rico? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
SouthwestOverall score based on 4270 reviews
8.0Comfort
8.6Crew
8.1Boarding
7.0Food
7.5Entertainment
Airline reviews

The first time I flew in the extra legroom section. It was difficult to notice a difference. I had bad luck with my neighbors. The crew was okay. Southwest has reduced the live TV options.

4.0 OkayAnonymous, May 2026
MDW - LAX
Read more Southwest reviews

The first time I flew in the extra legroom section. It was difficult to notice a difference. I had bad luck with my neighbors. The crew was okay. Southwest has reduced the live TV options.

The flight was smooth. The Southwest experience has degraded overall, but this one was okay.

No gluten free snacks. Seats felt worn or bare bones even though it was a new 737 MAX 8.

One major problem that was very unprofessional and uncalled for. Plane landed and we had to wait 20 minutes to get off the plane since they were waiting for someone to come to the gate to drive the jetway. Southwest couldn't have someone available and waiting for the plane to land? Is there only one person in Hobby airport who knows to drive the jetway? Was he at lunch? In the bar? Uncomfortable and uncalled for!

The checking experience in Orlando was terrible, almost missed the flight. Too many travelers and Southwest completely understaffed.

I'm glad it wasn't only 75% full because I could get a good seat

if I was good. Not happy that I have to pay extra money to get the seat I need for lake room, but I guess that’s a sign of the times.

Seats were very comfortable. They tilted back. Drinks and snacks were free and served 3 times. Attendants were awesome.

Plane was clean and comfortable. Flight attendants and gate staff were professional, friendly and efficient. Boarding and deplaning were orderly and efficient. All in all, the typical excellent Southwest experience.

Truly terrible. Will never willingly fly southwest again. Seats are worse than before they switched to assigned seating. One flight attendant was the opposite of helpful (rude, unhelpful, dismissive, and as my stranger seatmate said unprompted: a total prick). This caused me, 15 minutes into the flight, to book an alternate return flight home on a competing airline (first class 1.2k purchase instead of my existing planned flight) just so I would not have to ever be on that aircraft, with that terrible service person, with those horrific seats ever again.

Planes were clean, no water or snacks on either flight.

Free & relatively fast Wi-Fi. Would've liked a wider drink selection.

I continue to be satisfied with Delta’s excellent service out of LGA. The digit id works well and gets me through security in no time. Whenever possible, I choose Delta.

Was revoked with Jet Blue due to delay from Kenya Air

The Boarding process was great. Particularly since my wife and I require assistance. The flight attendants were amazing. We travel frequently; they honestly were a cut above. 😀

Enjoyed it very much. Especially liked the free WiFi that Delta offers.

Smooth flight. Left on time, and got in 15 minutes early. Onboard video was great

For some reason, TSA Atlanta didn’t have my bag on the flight on time and they don’t have to provide Delta a reason for that.

WiFi didn’t work on two of four planes. Flight attendants were not overly friendly or welcoming. Planes were extremely slow to board and deplane.

Delta does a great job with entertainment and free wifi. I can still be in touch with my colleagues while in the air.

Easy of boarding, helpfully staff at check in, surprisingly comfortable seating

Check in was chaotic with only one counter for business class and first class. The luggage conveyor belt at JFK airport was broken so the flight departure was delayed which made the flight stressful as I had a tight connection. Although the captain said they could make up the delay, they didn’t do so.

Had a one hour delay due to mechanical issue. I didn’t think I’d be able to make my connecting flight, but they waited for me and greeted me when I arrived to help things run smooth.

Lost of requested seat assignments. Lost my husband's meal choice

6 1/2 hours from Tampa to SFO on a Boeing 737. Cramped. No Service. No real food. One pass for coffee at the beginning and a second pass THREE hours later. And check-in in Tampa was nasty even by United standards. And I am at almost TWO million miles on United. It's a non-stop. But terrible service.

MY FAMILY'S LUGGAGE WAS LOST FROM ROME TO BARI. I WAS THE ONLY ONE THAT RECEIVED MY LUGGAGE FROM ROME TO BARI. AFTER DEPLANING IN BARI, WE WASTED A LOT OF TIME AT BAG CLAIMS LOST AND FOUND REPORTING THE CLAIM AND PLEADING FOR THE BAGS TO BE DELIVERED THE NEXT DAY. WE WERE TOLD THAT IT TAKES 3 DAYS MINIMUM TO DELIVER. MY DAUGHTER AND MY GIRLFRIEND NEEDED THEIR PERSONAL THINGS AND WE WERE STAYING 3 HOURS AWAY FROM THE BARI AIRPORT. WE HAD TO DRIVE 3 HOURS TO THE AIRPORT TO COLLECT OUR LOST LUGGAGE THE NEXT DAY. WE ARE NOT HAPPY WITH THE EXPERIENCE

We had a delay, but thankfully I made it to my connection. Overall it went smooth

The flight had a delay but I made it to my connection. Flight was smooth overall

As I wrote earlier, poor planning and/or communication. At least twice, we were told that we would be boarding in less than ten minutes, only to have the flight again delayed at least another hour.

This flight is a quick way to get to Chicago, but a bit expensive.

We got delayed getting out of DFW for broken overhead bins. Once the flight got underway the captain kept the seatbelt sign lit the entire flight despite little perceptible turbulence, preventing use of the rest rooms and any sort of refreshment service in the main cabin.

Flight delays for communication overall not a good experience uncomfortable on the plane. Person in front of me reclined his seat, putting them inches from my lap.

There were flight delays making our flight arrive at our destination after midnight didn’t seem to have enough crew or airplanes for the flights laid over in Dallas should’ve had plenty of time to make it to our next flight only made it because that flight was also delayed because our plane wasn’t even at the airport yet overall have not had a good experience on American

Flight left on time. Captain provided relevant announcements. We had to wait 45 minutes to desembark due to the ramp closed because of lightening.

It's a long flight and that is always difficult. I was comfortable and well. The movies available were great and the crew was good.

Cancelled flight. Still waiting to get home for grand daughter’s graduation .

So overall the flight was just average and nothing special. They overbooked some of the flights and they ended up running out of overhead storage space so we had to check our carry-ons which wasn't terrible but we were inconvenienced because of the second connecting flight with a long layover we couldn't get our bags until the final destination. Most of the flight attendants were pretty good and overall the meals were not that great because the chicken was dry and overcooked. They also didn't provide butter or any kind of spread with the bread which is cheap and concerning. The American airlines staff at the check-in counter was kind of unprofessional because this lady just started singing in the middle of checking us in and that's weird. The worst part of the flights was the terrible conditions of the bathrooms which were unclean and did not have toilet paper or toilet tissue available which is kind of insane for a 14-hour and 8 and 1/2 hour flight.

Requested early boarding to disinfect seat, tray table, etc. before general boarding. Instructed to board after wheelchair passengers. Waited on jet bridge behind 12 wheelchair passengers. Stopped immediately after entering plane to wait for gate agent in rear of plane cleaning a seat that was wet, got to my row and found both seats adjacent to mine already occupied, with the lack of room making it impossible for me to clean my own space and defeating the purpose of my boarding early. Cleaned the armrests and tray table as best I could.

Seat bottom cushions are not good. I’m 165# & they hurt my butt. Plenty of legroom.

The wifi experience is awful. I had to try again and again, taking over 30 minutes, to connect to the wifi. I had to watch the same two ads over and over until I was finally successful. Once connected, it was anything but "high speed" and disconnected at least three times during the flight.

There weren't enough employees at check in took awhile to get bags checked. There wasn't a wheel chair for me, I was sent to someone who turns out to work for a different airline, if My flight hadn't been delayed I probably would have missed my flight as it was, by the time I arrived at my gate, they started boarding in about 15 minutes. I don't know who took me to my gate, definitely was not the normal people who take passengers to the gate. I'm guessing she may have been in a management position. I wish I knew her name, she went beyond to help me. With that said everyone was kind, and were doing the best they could. So, I choose to say it was an Adventure, stressful start, but good. In the end went well. The situation was not only difficult for passengers but the employee's.

The staff at the check in counter was so rude. Made you feel Incompetent

Frontier scheduled a 40 minute connection in DEN. What they failed to mention was that they “close the doors” 20 mins prior to departure, which means you only have 20 mins. Not enough time. Possibly against DOT regulations. Filing complaint.

Flight was scheduled at 9:40pm. Got delayed to 10 am, the next day. crazy

The bag check, flight check-in, and onboard experience convinced my wife and me that we will actively go out of our way to avoid flying Frontier Airlines in the future. At bag check, we were informed that check-in could only be completed via the Frontier mobile app. Unfortunately, the app was extremely frustrating—sending us through repetitive, confusing loops that repeatedly forced us to decline add-on services with nearly every click. While most airline apps upsell, this one felt intentionally exhausting. As the process dragged on, we became genuinely concerned that my phone battery would die before check-in could be completed. We approached the bag check staff—who were standing together talking—and explained both our frustration and our predicament. They laughed. Later, my wife described the interaction as “gaslighting,” which felt accurate. We were then informed it would cost $25 per person simply to have our boarding passes printed. From that point forward, the tone of the experience was consistently hostile. The bag check employees were condescending and combative, behaving more like bullies than customer service staff. Unfortunately, that same attitude continued onboard. One flight attendant argued with me when I attempted to stow my backpack in the overhead bin. I explained that we had each paid $75 to check our bags specifically so we would not need to use carry-on space and could have adequate legroom. She demanded to see my ticket, pointed out that it said “no carry-on”—which I acknowledged—and I reiterated that this was precisely why we paid to check our bags. Her response was, “I don’t make the rules.” She then walked away, but not before asking if I “truly wanted to fly back to Chicago today?”—an unnecessary and unmistakable threat. It is also worth noting that despite booking our tickets together in the same transaction, we were not seated together. Upon our return to Chicago—where we could once again sit together—we compared onboard experiences. We both remarked on how unhappy the flight attendants appeared and how each of us was separately asked whether we would like to purchase a beverage. We declined. At no point was water mentioned as an option, leaving us with the clear impression that even water came at a cost—or that complimentary water, if available at all, was deliberately left unmentioned. Overall, the experience was shocking and deeply disappointing, but it was also a profound learning experience—one we will not forget and will not repeat. -Steve

Plane was hot and miserable and the crew was rude!

12 hour delay required getting on and off plane 3 times - would have at least liked to have been offered a snack or drink

They didn’t offer a water, even after I asked

They switched our terminal 3 times and we were delayed for four plus hours!!!

It was an early flight and most people napped/slept and the crew let us which was nice.

Everything you need to know for your flight from St. Louis to Puerto Rico

Information on your arrival and departure airports