What are the cheapest airlines to fly from St. Louis to Caribbean Islands one-way?

$103 is the cheapest one-way deal found within the past few days, from Delta. You may also be able to find cheap deals on American Airlines and United Airlines, with prices starting from $109 and $117, respectively.

In terms of precipitation, rainfall in Caribbean Islands ranges from 2.2 - 6.1 inches per month. November is typically the wettest month, when rainfall can reach 6.1 in. February is typically the driest time to visit Caribbean Islands when rainfall is around 2.2 in.

If weather is an important factor for your trip to Caribbean Islands, use this chart to help with planning. For those seeking warmer temperatures, June is the ideal time of year to visit, when temperatures reach an average of 82.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 77.0 F).

What are the most popular routes from St. Louis to Caribbean Islands?

The most popular route from St. Louis to Caribbean Islands is Lambert-St Louis - San Juan Luis Munoz Marin Intl. You may also consider Lambert-St Louis - Nassau Intl or Lambert-St Louis - Punta Cana.

What are the most popular airlines that fly from St. Louis to Caribbean Islands?

Before booking your flight from St. Louis to Caribbean Islands check out the most popular airlines for this route: American Airlines, Delta or Frontier.

How far in advance should I book a flight from St. Louis to Caribbean Islands?

To save on the cost of your flight from St. Louis to Caribbean Islands, book at least 24 days before your planned departure. Booking around this time can save you about 137% on the cost of this flight compared to booking a flight leaving this week. We have found prices from $328 if you need a flight within two weeks. For flights within the next 72 hours, you can find tickets from as low as $531.

What is the cheapest month to fly from St. Louis to Caribbean Islands?

Flights from St. Louis to Caribbean Islands lean towards being more expensive in December. Prices are generally better when you fly from St. Louis to Caribbean Islands in September, with the cheapest ticket starting at $197.

What airport do you fly from for flights from St. Louis to Caribbean Islands?

Located just 12.7 mi from the city center, Lambert-St Louis (STL) is the airport most travelers will use when flying to Caribbean Islands from St. Louis.

Can I find deals for flights from St. Louis to Caribbean Islands that include hotel bookings?

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

How can I find direct flights from St. Louis to Caribbean Islands?

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

Can I find deals for business class flights from St. Louis to Caribbean Islands?

Yes. Cheapflights offers flight deals from St. Louis to Caribbean Islands by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$103+ Flights from St. Louis to Caribbean Islands

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Cheap flight deals from St. Louis to Caribbean Islands

Round-trip from	$205 (Delta)
One-way from	$103 (Delta)
Popular in	December
Cheapest in	September
Average price	$462

From Lambert-St Louis to Caribbean Islands

Search Deals

One-way flight from Lambert-St Louis to Caribbean Islands

Search Deals

Highest demand for flights based on searches. 7% potential increase in price ($35 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease ($14 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in August 2025

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Find flight deals from St. Louis to Caribbean Islands

Cheapest flights from St. Louis to Caribbean Islands
Explore the most affordable flight options available from St. Louis to Caribbean Islands. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 14, 2025.

Sat 10/256:00 amSTL - SJU

1 stop7h 11mDelta

Sat 11/17:15 amSJU - STL

1 stop8h 28mDelta

Deal found 8/14

$205

Tue 10/146:15 amSTL - SJU

1 stop8h 27mUnited Airlines

Mon 10/271:05 amSJU - STL

2 stops14h 20mUnited Airlines

Deal found 8/13

$220

Sat 10/187:00 pmSTL - STT

1 stop13h 56mSpirit Airlines

Sat 10/2511:01 amSTT - STL

1 stop7h 44mSpirit Airlines

Deal found 8/14

$261

Tue 12/96:00 amSTL - SJU

1 stop6h 15mDelta

Fri 12/123:30 pmSJU - STL

1 stop10h 09mDelta

Deal found 8/12

$265

Fri 12/59:45 amSTL - SJU

1 stop8h 42mFrontier

Fri 12/1211:05 amSJU - STL

1 stop13h 41mFrontier

Deal found 8/13

$269

Sun 9/2110:35 amSTL - SJU

1 stop23h 29mSpirit Airlines

Sat 9/273:19 pmSJU - STL

2 stops19h 21mSpirit Airlines

Deal found 8/13

$271

Thu 8/282:30 pmSTL - SJU

2 stops9h 26mSpirit Airlines

Sat 8/302:11 amSJU - STL

2 stops12h 21mSpirit Airlines

Deal found 8/12

$277

Sat 10/45:18 amSTL - SJU

1 stop7h 57mAmerican Airlines

Tue 10/73:34 pmSJU - STL

1 stop8h 44mAmerican Airlines

Deal found 8/14

$278

Sat 9/67:00 amSTL - SJU

1 stop8h 36mDelta

Sat 9/132:15 pmSJU - STL

1 stop8h 35mDelta

Deal found 8/13

$283

Fri 10/176:00 amSTL - SJU

1 stop16h 59mAmerican Airlines

Sun 10/197:10 amSJU - STL

1 stop17h 48mAmerican Airlines

Deal found 8/12

$284

Mon 9/151:57 pmSTL - SJU

1 stop9h 02mFrontier

Sat 9/203:39 amSJU - STL

1 stop10h 28mFrontier

Deal found 8/14

$286

Sun 8/175:40 pmSTL - SJU

1 stop7h 59mFrontier

Wed 8/208:13 pmSJU - STL

1 stop17h 54mFrontier

Deal found 8/14

$287

Best flights from St. Louis to Caribbean Islands
Discover carefully curated flight deals from St. Louis to Caribbean Islands that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated August 14, 2025.

Sat 10/2512:21 pmSTL - SJU

2 stops10h 33mAmerican Airlines

Sat 11/15:30 amSJU - STL

1 stop14h 12mAmerican Airlines

Deal found 8/12

$205

Sat 10/256:00 amSTL - SJU

1 stop7h 11mDelta

Sat 11/17:15 amSJU - STL

1 stop8h 28mDelta

Deal found 8/14

$205

Tue 9/235:25 amSTL - SJU

1 stop7h 45mSouthwest

Tue 9/305:00 amSJU - STL

1 stop9h 30mSouthwest

Deal found 8/13

$205

Sat 10/187:00 pmSTL - STT

1 stop13h 56mSpirit Airlines

Sat 10/2511:01 amSTT - STL

1 stop7h 44mSpirit Airlines

Deal found 8/13

$261

Wed 10/227:52 pmSTL - STT

2 stops16h 07mMultiple Airlines

Wed 10/2911:01 amSTT - STL

1 stop24h 01mMultiple Airlines

Deal found 8/14

$323

Thu 9/44:00 pmSTL - MBJ

1 stop20h 45mFrontier

Sun 9/72:12 pmMBJ - STL

1 stop24h 52mFrontier

Deal found 8/13

$401

Wed 10/2210:36 amSTL - SJU

1 stop12h 23mAmerican Airlines

Tue 10/283:34 pmSJU - STL

1 stop18h 19mAmerican Airlines

Deal found 8/13

$205

Sat 10/186:00 amSTL - SJU

1 stop7h 11mDelta

Wed 10/227:15 amSJU - STL

1 stop8h 28mDelta

Deal found 8/14

$205

Wed 10/156:00 amSTL - SJU

1 stop16h 59mAmerican Airlines

Wed 10/295:00 pmSJU - STL

1 stop7h 56mAmerican Airlines

Deal found 8/13

$205

Mon 9/228:50 amSTL - SJU

2 stops13h 47mAmerican Airlines

Sat 9/273:05 pmSJU - STL

1 stop8h 45mAmerican Airlines

Deal found 8/12

$205

Sun 11/24:05 pmSTL - CUR

1 stop22h 15mAir Canada

Fri 11/74:10 pmCUR - STL

2 stops25h 19mAir Canada

Deal found 8/13

$498

Sun 9/215:18 amSTL - SJU

1 stop7h 57mAmerican Airlines

Sat 9/273:05 pmSJU - STL

1 stop8h 45mAmerican Airlines

Deal found 8/12

$205

Last-minute flights from St. Louis to Caribbean Islands
Discover last-minute flight deals from St. Louis to Caribbean Islands. Data last updated August 14, 2025 and is based on user searches.

Fri 8/155:40 pmSTL - SJU

1 stop7h 59mFrontier

Thu 8/213:59 amSJU - STL

1 stop11h 22mFrontier

Deal found 8/14

$269

Sun 8/175:40 pmSTL - SJU

1 stop7h 59mFrontier

Wed 8/208:13 pmSJU - STL

1 stop17h 54mFrontier

Deal found 8/14

$287

Tue 8/198:00 amSTL - SJU

1 stop10h 08mMultiple Airlines

Sun 8/244:12 pmSJU - STL

1 stop22h 20mMultiple Airlines

Deal found 8/13

$336

Tue 8/198:00 amSTL - SJU

1 stop10h 08mFrontier

Sat 8/233:59 amSJU - STL

1 stop10h 08mFrontier

Deal found 8/13

$346

Tue 8/198:00 amSTL - SJU

1 stop10h 08mMultiple Airlines

Sun 8/242:11 amSJU - STL

2 stops12h 21mMultiple Airlines

Deal found 8/13

$381

Tue 8/198:00 amSTL - SJU

1 stop10h 08mFrontier

Sun 8/243:59 amSJU - STL

1 stop11h 22mFrontier

Deal found 8/13

$416

Tue 8/198:00 amSTL - SJU

1 stop10h 08mMultiple Airlines

Fri 8/222:11 amSJU - STL

2 stops32h 29mMultiple Airlines

Deal found 8/13

$433

Tue 8/198:00 amSTL - SJU

1 stop10h 08mFrontier

Sat 8/233:21 pmSJU - STL

2 stops22h 46mFrontier

Deal found 8/13

$456

Wed 8/206:06 amSTL - PUJ

1 stop7h 09mAmerican Airlines

Wed 9/101:35 pmPUJ - STL

1 stop11h 24mAmerican Airlines

Deal found 8/12

$429

Thu 8/2110:37 amSTL - PUJ

1 stop27h 23mSpirit Airlines

Thu 8/2812:40 pmPUJ - STL

2 stops25h 52mSpirit Airlines

Deal found 8/14

$436

Thu 8/2110:37 amSTL - PUJ

1 stop27h 23mMultiple Airlines

Thu 8/2812:40 pmPUJ - STL

1 stop26h 41mMultiple Airlines

Deal found 8/14

$447

Sun 8/246:00 amSTL - MBJ

1 stop7h 05mDelta

Fri 9/51:20 pmMBJ - STL

1 stop8h 42mDelta

Deal found 8/13

$446

One-way flights from St. Louis to Caribbean Islands
Search for one-way flight options from St. Louis to Caribbean Islands. Find affordable one-way fares based on user searches. Data last updated August 14, 2025.

Mon 9/226:01 amSTL - SJU

1 stop6h 15mDelta

Deal found 8/14

$103

Wed 10/16:00 pmSTL - SJU

2 stops17h 47mAmerican Airlines

Deal found 8/14

$109

Thu 10/212:25 pmSTL - NAS

2 stops24h 06mUnited Airlines

Deal found 8/12

$117

Tue 11/1810:00 amSTL - SJU

2 stops10h 22mUnited Airlines

Deal found 8/14

$118

Sat 9/279:20 amSTL - SJU

2 stops13h 37mUnited Airlines

Deal found 8/14

$121

Sat 11/152:22 pmSTL - SJU

1 stop10h 32mFrontier

Deal found 8/12

$126

Sat 10/116:00 amSTL - SJU

1 stop16h 05mAmerican Airlines

Deal found 8/13

$128

Tue 11/410:57 amSTL - SJU

2 stops20h 55mSpirit Airlines

Deal found 8/14

$132

Wed 9/105:28 amSTL - SJU

1 stop9h 52mAmerican Airlines

Deal found 8/14

$133

Fri 10/106:05 pmSTL - SJU

1 stop7h 25mFrontier

Deal found 8/14

$135

Fri 11/145:56 pmSTL - SJU

2 stops16h 09mAmerican Airlines

Deal found 8/14

$139

Fri 10/247:05 amSTL - NAS

1 stop5h 44mDelta

Deal found 8/14

$139

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Caribbean Islands that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 10/25

12:21 pm-11:54 pm

2 stops10h 33m

San Juan Luis Munoz Marin Intl

Sat 11/1

5:30 am-6:42 pm

1 stop14h 12m

$205

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 10/25

6:00 am-2:11 pm

1 stop7h 11m

San Juan Luis Munoz Marin Intl

Sat 11/1

7:15 am-2:43 pm

1 stop8h 28m

$205

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Tue 9/23

5:25 am-2:10 pm

1 stop7h 45m

San Juan Luis Munoz Marin Intl

Tue 9/30

5:00 am-1:30 pm

1 stop9h 30m

$205

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Wed 10/22

10:36 am-11:59 pm

1 stop12h 23m

San Juan Luis Munoz Marin Intl

Tue 10/28

3:34 pm-8:53 am

1 stop18h 19m

$205

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sat 10/18

6:00 am-2:11 pm

1 stop7h 11m

San Juan Luis Munoz Marin Intl

Wed 10/22

7:15 am-2:43 pm

1 stop8h 28m

$205

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Wed 10/15

6:00 am-11:59 pm

1 stop16h 59m

San Juan Luis Munoz Marin Intl

Wed 10/29

5:00 pm-11:56 pm

1 stop7h 56m

$205

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Mon 9/22

8:50 am-11:37 pm

2 stops13h 47m

San Juan Luis Munoz Marin Intl

Sat 9/27

3:05 pm-10:50 pm

1 stop8h 45m

$205

St. LouisSan Juan

STL - SJU

STLSJU

Lambert-St Louis

Sun 9/21

5:18 am-2:15 pm

1 stop7h 57m

San Juan Luis Munoz Marin Intl

Sat 9/27

3:05 pm-10:50 pm

1 stop8h 45m

$205

St. LouisSaint Thomas Island

STL - STT

STLSTT

Lambert-St Louis

Sat 10/18

7:00 pm-9:56 am

1 stop13h 56m

Saint Thomas Island Cyril E King

Sat 10/25

11:01 am-5:45 pm

1 stop7h 44m

$261

St. LouisNassau

STL - NAS

STLNAS

Lambert-St Louis

Wed 10/1

6:01 am-1:49 pm

1 stop6h 48m

Nassau Intl

Wed 10/8

1:16 pm-6:02 pm

1 stop5h 46m

$305

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/12

Showing 1-10 of 60 results

...

Best time to book a flight from St. Louis to Caribbean Islands

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

What is the cheapest month to book a flight from St. Louis to Caribbean Islands?

Currently, September is the cheapest month in which you can book a flight from St. Louis to Caribbean Islands (average of $254). Flying from St. Louis to Caribbean Islands in June is currently the most expensive (average of $339). 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 EPX?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from St. Louis to Caribbean Islands as you normally would.

Reviews of airlines servicing Caribbean Islands

Read reviews from past customers who have flown Southwest, Delta, and United Airlines from St. Louis to Caribbean Islands. 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

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Dozens of flights and I've never seen a row's beverages forgotten. I even went back and asked the attendant to check on them and nothing. I really hope it didn't have something to do with the Black mother with her kid in the row. Otherwise it was a typical Southwest flight, rapid boarding, tolerable leg room.

Southwest

8.0

Very good

4,244 reviews

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Delta

8.0

Very good

7,980 reviews

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

United Airlines

7.4

Good

8,916 reviews

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

American Airlines

7.2

Good

10,000 reviews

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Frontier

5.8

Fair

3,217 reviews

Southwest

8.0

Very good

4,244 reviews

Reviews

1 / 20

8.0

Excellent

Walter,Aug 2025

OAK - SAN

Related info for your journey

What airport do you fly from for flights from St. Louis to Caribbean Islands?
Located just 12.7 mi from the city center, Lambert-St Louis (STL) is the airport most travelers will use when flying to Caribbean Islands from St. Louis.
What are the cheapest airlines to fly from St. Louis to Caribbean Islands one-way?
$103 is the cheapest one-way deal found within the past few days, from Delta. You may also be able to find cheap deals on American Airlines and United Airlines, with prices starting from $109 and $117, respectively.
What are the most popular routes from St. Louis to Caribbean Islands?
The most popular route from St. Louis to Caribbean Islands is Lambert-St Louis - San Juan Luis Munoz Marin Intl. You may also consider Lambert-St Louis - Nassau Intl or Lambert-St Louis - Punta Cana.
Can I find deals for flights from St. Louis to Caribbean Islands that include hotel bookings?
Yes. In addition to deals on St. Louis to Caribbean Islands flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from St. Louis to Caribbean Islands?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from St. Louis to Caribbean Islands.
Can I find deals for business class flights from St. Louis to Caribbean Islands?
Yes. Cheapflights offers flight deals from St. Louis to Caribbean Islands 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 St. Louis to Caribbean Islands?
Currently, September is the cheapest month in which you can book a flight from St. Louis to Caribbean Islands (average of $254). Flying from St. Louis to Caribbean Islands in June is currently the most expensive (average of $339). 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

Browse thousands of different options on Cheapflights for your next trip

Top 6 airlines flying from St. Louis to Caribbean Islands

Airline	Cheapest	Average	Flexibility	On-time
Frontier	Cheapest$140	Average$390	FlexibilityNo cancel fee	On-time62%
Spirit Airlines	Cheapest$170	Average$329	FlexibilityNo cancel fee	On-time65%
Delta	Cheapest$209	Average$594	FlexibilityNo cancel fee	On-timeN/A
United Airlines	Cheapest$219	Average$541	FlexibilityNo cancel fee	On-time69%
Southwest	Cheapest$219	Average$732	FlexibilityNo cancel fee	On-time63%
American Airlines	Cheapest$257	Average$630	FlexibilityNo cancel fee	On-time71%

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$103+ Cheap flights from St. Louis (STL) to Caribbean Islands

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 9/22. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from St. Louis to Caribbean Islands with Cheapflights

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3. Compare prices and book

Cheap flight deals from St. Louis to Caribbean Islands

Keep the following information in mind while searching for St. Louis to Caribbean Islands flight deals. Data was last updated August 14, 2025.

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Find flight deals from St. Louis to Caribbean Islands

Cheapest flights from St. Louis to Caribbean IslandsExplore the most affordable flight options available from St. Louis to Caribbean Islands. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 14, 2025.

Explore the most affordable flight options available from St. Louis to Caribbean Islands. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 14, 2025.

Cheapflights Fare Finder

Use the filters below to find and compare flights from St. Louis to Caribbean Islands that are best for you.

Best time to book a flight from St. Louis to Caribbean Islands

Have a flexible travel schedule? Discover the best time to fly to Caribbean Islands from St. Louis with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from St. Louis to Caribbean Islands

What is the cheapest month to book a flight from St. Louis to Caribbean Islands?

What is the cheapest time of day to fly from STL to EPX?

Find hourly flight availability from St. Louis to Caribbean Islands. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated August 14, 2025.

Reviews of airlines servicing Caribbean Islands

Read reviews from past customers who have flown Southwest, Delta, and United Airlines from St. Louis to Caribbean Islands. You can also see how each airline compares in terms of entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from St. Louis to Caribbean Islands. 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 from for flights from St. Louis to Caribbean Islands?

What are the cheapest airlines to fly from St. Louis to Caribbean Islands one-way?

What are the most popular routes from St. Louis to Caribbean Islands?

Can I find deals for flights from St. Louis to Caribbean Islands that include hotel bookings?

How can I find direct flights from St. Louis to Caribbean Islands?

Can I find deals for business class flights from St. Louis to Caribbean Islands?

What is the cheapest month to book a flight from St. Louis to Caribbean Islands?

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for St. Louis to Caribbean Islands

See prices for flight routes from nearby airports that may be better suited for you.

Top 6 airlines flying from St. Louis to Caribbean Islands

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Cheapest flights from St. Louis to Caribbean Islands
Explore the most affordable flight options available from St. Louis to Caribbean Islands. Find the lowest fares from popular airlines and budget airlines, with prices last updated on August 14, 2025.