$100+ Cheap flights from St. Louis (STL) to San Juan
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 4/7. Fares are subject to change and may not be available on all flights or dates of travel.
STL — SJU
Apr 10 — Apr 171
Round-trip
1 adult, Economy
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Find cheap flights from St. Louis to San Juan with Cheapflights
1. Tell us where you want to go
Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”2. Select your favorite providers
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Cheapest flights from St. Louis to San JuanExplore the most affordable flight options available from St. Louis to San Juan. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 11, 2026.
Explore the most affordable flight options available from St. Louis to San Juan. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 11, 2026.
This Priceline deal was found by Cheapflights users on 3/6. 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.
Tue 4/74:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Mon 4/133:08 am
SJU
- STL
1 stop21h 11m
Frontier
Deal found 3/6![Frontier logo]()
$202
This CheapOair deal was found by Cheapflights users on 3/5. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/138:41 am
STL
- SJU
1 stop10h 19m
Frontier
Fri 4/176:30 am
SJU
- STL
1 stop17h 49m
Frontier
Deal found 3/5![Frontier logo]()
$213
This CheapOair deal was found by Cheapflights users on 3/6. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/94:55 pm
STL
- SJU
1 stop8h 06m
Frontier
Tue 5/123:08 am
SJU
- STL
1 stop21h 11m
Frontier
Deal found 3/6![Frontier logo]()
$221
This American Airlines deal was found by Cheapflights users on 3/6. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/266:29 am
STL
- SJU
1 stop7h 00m
American Airlines
Thu 4/306:45 am
SJU
- STL
1 stop11h 36m
American Airlines
Deal found 3/6![American Airlines logo]()
$222
This Frontier deal was found by Cheapflights users on 3/8. 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.
Mon 5/44:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Thu 5/711:07 am
SJU
- STL
1 stop13h 12m
Frontier
Deal found 3/8![Frontier logo]()
$223
This American Airlines deal was found by Cheapflights users on 3/9. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/226:29 am
STL
- SJU
1 stop14h 36m
American Airlines
Thu 4/3011:59 pm
SJU
- STL
1 stop9h 55m
American Airlines
Deal found 3/9![American Airlines logo]()
$227
This CheapOair deal was found by Cheapflights users on 3/6. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/3111:27 am
STL
- SJU
1 stop12h 30m
Frontier
Tue 4/76:30 am
SJU
- STL
1 stop17h 55m
Frontier
Deal found 3/6![Frontier logo]()
$234
This Frontier deal was found by Cheapflights users on 3/9. 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.
Tue 3/314:51 pm
STL
- SJU
1 stop8h 12m
Frontier
Mon 4/612:28 pm
SJU
- STL
1 stop11h 57m
Frontier
Deal found 3/9![Frontier logo]()
$239
This CheapOair deal was found by Cheapflights users on 3/9. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 5/94:55 pm
STL
- SJU
1 stop8h 06m
Frontier
Mon 5/113:08 am
SJU
- STL
1 stop21h 11m
Frontier
Deal found 3/9![Frontier logo]()
$241
This CheapOair deal was found by Cheapflights users on 3/10. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/154:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Wed 4/226:30 am
SJU
- STL
1 stop17h 49m
Frontier
Deal found 3/10![Frontier logo]()
$242
This CheapOair deal was found by Cheapflights users on 3/8. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/84:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Sat 4/113:21 am
SJU
- STL
1 stop29h 30m
Frontier
Deal found 3/8![Frontier logo]()
$243
This Frontier deal was found by Cheapflights users on 3/9. 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.
Fri 5/84:55 pm
STL
- SJU
1 stop8h 06m
Frontier
Wed 5/1311:07 am
SJU
- STL
1 stop13h 12m
Frontier
Deal found 3/9![Frontier logo]()
$244
Best flights from St. Louis to San JuanDiscover carefully curated flight deals from St. Louis to San Juan that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 11, 2026.
Discover carefully curated flight deals from St. Louis to San Juan that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated March 11, 2026.
This United Airlines deal was found by Cheapflights users on 3/6. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 5/39:21 am
STL
- SJU
1 stop10h 13m
United Airlines
Thu 5/77:20 am
SJU
- STL
2 stops14h 53m
United Airlines
Deal found 3/6![United Airlines logo]()
$312
This Southwest deal was found by Cheapflights users on 3/9. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 5/152:25 pm
STL
- SJU
1 stop8h 00m
Southwest
Mon 5/185:35 am
SJU
- STL
2 stops10h 55m
Southwest
Deal found 3/9![Southwest logo]()
$448
This United Airlines deal was found by Cheapflights users on 3/8. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/47:45 am
STL
- SJU
2 stops12h 39m
United Airlines
Thu 5/77:20 am
SJU
- STL
2 stops14h 53m
United Airlines
Deal found 3/8![United Airlines logo]()
$312
This United Airlines deal was found by Cheapflights users on 3/7. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/139:10 am
STL
- SJU
1 stop10h 24m
United Airlines
Thu 4/161:00 am
SJU
- STL
2 stops12h 22m
United Airlines
Deal found 3/7![United Airlines logo]()
$312
This Southwest deal was found by Cheapflights users on 3/8. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 5/202:05 pm
STL
- SJU
1 stop6h 00m
Southwest
Sun 5/245:45 am
SJU
- STL
1 stop11h 50m
Southwest
Deal found 3/8![Southwest logo]()
$512
This Southwest deal was found by Cheapflights users on 3/6. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/59:55 am
STL
- SJU
2 stops13h 20m
Southwest
Sat 6/139:25 pm
SJU
- STL
1 stop12h 00m
Southwest
Deal found 3/6![Southwest logo]()
$521
This United Airlines deal was found by Cheapflights users on 3/8. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/189:16 am
STL
- SJU
2 stops13h 34m
United Airlines
Fri 4/241:00 am
SJU
- STL
2 stops14h 24m
United Airlines
Deal found 3/8![United Airlines logo]()
$509
This Southwest deal was found by Cheapflights users on 3/6. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/252:25 pm
STL
- SJU
2 stops8h 15m
Southwest
Mon 4/275:05 am
SJU
- STL
2 stops9h 40m
Southwest
Deal found 3/6![Southwest logo]()
$521
This United Airlines deal was found by Cheapflights users on 3/8. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 5/259:23 am
STL
- SJU
2 stops13h 27m
United Airlines
Thu 5/282:05 am
SJU
- STL
1 stop9h 02m
United Airlines
Deal found 3/8![United Airlines logo]()
$536
Last-minute flights from St. Louis to San JuanDiscover last-minute flight deals from St. Louis to San Juan. Data last updated March 11, 2026 and is based on user searches.
Discover last-minute flight deals from St. Louis to San Juan. Data last updated March 11, 2026 and is based on user searches.
This CheapOair deal was found by Cheapflights users on 3/6. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 3/3111:27 am
STL
- SJU
1 stop12h 30m
Frontier
Tue 4/76:30 am
SJU
- STL
1 stop17h 55m
Frontier
Deal found 3/6![Frontier logo]()
$234
This Frontier deal was found by Cheapflights users on 3/9. 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.
Tue 3/314:51 pm
STL
- SJU
1 stop8h 12m
Frontier
Mon 4/612:28 pm
SJU
- STL
1 stop11h 57m
Frontier
Deal found 3/9![Frontier logo]()
$239
This Priceline deal was found by Cheapflights users on 3/6. 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.
Tue 4/74:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Mon 4/133:08 am
SJU
- STL
1 stop21h 11m
Frontier
Deal found 3/6![Frontier logo]()
$202
This Kiwi.com deal was found by Cheapflights users on 3/6. 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.
Tue 4/711:21 am
STL
- SJU
2 stops13h 40m
Frontier
Fri 4/173:23 pm
SJU
- STL
1 stop16h 27m
Frontier
Deal found 3/6![Frontier logo]()
$248
This CheapOair deal was found by Cheapflights users on 3/6. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/84:59 pm
STL
- SJU
1 stop6h 03m
Frontier
Mon 4/133:08 am
SJU
- STL
1 stop21h 11m
Frontier
Deal found 3/6![Frontier logo]()
$221
This CheapOair deal was found by Cheapflights users on 3/8. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/84:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Sat 4/113:21 am
SJU
- STL
1 stop29h 30m
Frontier
Deal found 3/8![Frontier logo]()
$243
This Kiwi.com deal was found by Cheapflights users on 3/6. 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 4/96:29 pm
STL
- SJU
1 stop24h 21m
Multiple Airlines
Fri 4/173:23 pm
SJU
- STL
1 stop16h 27m
Multiple Airlines
Deal found 3/6![Multiple Airlines logo]()
$247
This CheapOair deal was found by Cheapflights users on 3/5. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/138:41 am
STL
- SJU
1 stop10h 19m
Frontier
Fri 4/176:30 am
SJU
- STL
1 stop17h 49m
Frontier
Deal found 3/5![Frontier logo]()
$213
This CheapOair deal was found by Cheapflights users on 3/10. 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 CheapOair is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/154:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Wed 4/226:30 am
SJU
- STL
1 stop17h 49m
Frontier
Deal found 3/10![Frontier logo]()
$242
This American Airlines deal was found by Cheapflights users on 3/9. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/226:29 am
STL
- SJU
1 stop14h 36m
American Airlines
Thu 4/3011:59 pm
SJU
- STL
1 stop9h 55m
American Airlines
Deal found 3/9![American Airlines logo]()
$227
This American Airlines deal was found by Cheapflights users on 3/6. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/266:29 am
STL
- SJU
1 stop7h 00m
American Airlines
Thu 4/306:45 am
SJU
- STL
1 stop11h 36m
American Airlines
Deal found 3/6![American Airlines logo]()
$222
One-way flights from St. Louis to San JuanSearch for one-way flight options from St. Louis to San Juan. Find affordable one-way fares based on user searches. Data last updated March 11, 2026.
Search for one-way flight options from St. Louis to San Juan. Find affordable one-way fares based on user searches. Data last updated March 11, 2026.
This Super.com deal was found by Cheapflights users on 3/6. 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 Super.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/74:59 pm
STL
- SJU
1 stop15h 19m
Frontier
Deal found 3/6![Frontier logo]()
$100
This Priceline deal was found by Cheapflights users on 3/6. 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 4/184:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Deal found 3/6![Frontier logo]()
$101
This Priceline deal was found by Cheapflights users on 3/9. 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.
Thu 4/94:59 pm
STL
- SJU
1 stop26h 01m
Frontier
Deal found 3/9![Frontier logo]()
$107
This Delta deal was found by Cheapflights users on 3/9. 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 Delta is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/1411:42 am
STL
- SJU
1 stop7h 42m
Delta
Deal found 3/9![Delta logo]()
$111
This American Airlines deal was found by Cheapflights users on 3/9. 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 American Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/226:29 am
STL
- SJU
1 stop14h 36m
American Airlines
Deal found 3/9![American Airlines logo]()
$116
This Priceline deal was found by Cheapflights users on 3/10. 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.
Wed 5/274:44 pm
STL
- SJU
1 stop29h 38m
Frontier
Deal found 3/10![Frontier logo]()
$117
This Priceline deal was found by Cheapflights users on 3/8. 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.
Mon 3/304:51 pm
STL
- SJU
1 stop8h 07m
Frontier
Deal found 3/8![Frontier logo]()
$120
This United Airlines deal was found by Cheapflights users on 3/10. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 4/149:10 am
STL
- SJU
2 stops13h 40m
United Airlines
Deal found 3/10![United Airlines logo]()
$121
This Priceline deal was found by Cheapflights users on 3/6. 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.
Thu 4/234:59 pm
STL
- SJU
1 stop8h 02m
Frontier
Deal found 3/6![Frontier logo]()
$122
This United Airlines deal was found by Cheapflights users on 3/6. 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 United Airlines is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 4/199:10 am
STL
- SJU
2 stops11h 14m
United Airlines
Deal found 3/6![United Airlines logo]()
$124
Find flight deals from St. Louis to San Juan
Discover tips and strategies to find the most affordable flight options for your journey from St. Louis (STL) to San Juan (PR1). 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 March 11, 2026.
Round-trip from | $202 (Priceline) |
|---|---|
One-way from | $100 (Super.com) |
Popular in | December |
Cheapest in | September |
Average price | $406 |
Cheapflights Fare Finder
Customize your flight search to find flights from St. Louis to San Juan 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 March 11, 2026.
Use the filters below to find and compare flights from St. Louis to San Juan that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Sun 5/3
9:21 am-8:34 pm
1 stop10h 13m
San Juan Luis Munoz Marin Intl
Thu 5/7
7:20 am-9:13 pm
2 stops14h 53m
$312
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Mon 5/4
7:45 am-9:24 pm
2 stops12h 39m
San Juan Luis Munoz Marin Intl
Thu 5/7
7:20 am-9:13 pm
2 stops14h 53m
$312
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Mon 4/13
9:10 am-8:34 pm
1 stop10h 24m
San Juan Luis Munoz Marin Intl
Thu 4/16
1:00 am-12:22 pm
2 stops12h 22m
$312
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Fri 5/15
2:25 pm-11:25 pm
1 stop8h 00m
San Juan Luis Munoz Marin Intl
Mon 5/18
5:35 am-3:30 pm
2 stops10h 55m
$448
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Sat 4/18
9:16 am-11:50 pm
2 stops13h 34m
San Juan Luis Munoz Marin Intl
Fri 4/24
1:00 am-2:24 pm
2 stops14h 24m
$509
Quickest round-trip
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Wed 5/20
2:05 pm-9:05 pm
1 stop6h 00m
San Juan Luis Munoz Marin Intl
Sun 5/24
5:45 am-4:35 pm
1 stop11h 50m
$512
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Fri 6/5
9:55 am-12:15 am
2 stops13h 20m
San Juan Luis Munoz Marin Intl
Sat 6/13
9:25 pm-8:25 am
1 stop12h 00m
$521
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Sat 4/25
2:25 pm-11:40 pm
2 stops8h 15m
San Juan Luis Munoz Marin Intl
Mon 4/27
5:05 am-1:45 pm
2 stops9h 40m
$521
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Mon 5/25
9:23 am-11:50 pm
2 stops13h 27m
San Juan Luis Munoz Marin Intl
Thu 5/28
2:05 am-10:07 am
1 stop9h 02m
$536
Cheapest one-way
St. LouisSan Juan
STL - SJU
STLSJU
Lambert-St Louis
Tue 5/5
7:45 am-8:38 pm
2 stops11h 53m
$111
Showing 1-10 of 20 resultsSorted by cheapest first
Best time to book a flight from St. Louis to San Juan
Have a flexible travel schedule? Discover the best time to fly to San Juan from St. Louis with our price prediction graph.
STL-PR1
STL-SJU
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 San Juan
STL-PR1
STL-SJU
How far ahead should I book a flight from St. Louis to San Juan?
Use this chart to determine the optimal time to book a round-trip flight from St. Louis to San Juan. Price data was last updated on March 6, 2026.
The price you pay for your flight from St. Louis to San Juan may vary depending on when you book. For the best chance of a lower fare, look to book 75 days in advance of your trip. Fares are likely to increase a fortnight or so before your departure date.
What is the cheapest month to book a flight from St. Louis to San Juan?
Currently, July is the cheapest month in which you can book a flight from St. Louis to San Juan (average of $144). Flying from St. Louis to San Juan in April is currently the most expensive (average of $246). 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 SJU?
Find hourly flight availability from St. Louis to San Juan. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 11, 2026.
When flying from St. Louis to San Juan, the time of day you decide to fly out makes little to no difference towards the overall price you’ll pay on tickets.
How much does it cost to fly round-trip from St. Louis to San Juan?
How often are flights from St. Louis to San Juan delayed?
About 21% of weekly flights between St. Louis and San Juan have experienced delays in the past year, with the average delay time being 92 minutes.
What is the most punctual flight time for St. Louis to San Juan flights?
Historically, flights departing in the morning are less likely to be delayed, whereas flights leaving in the early afternoon tend to experience delays more often.
What day of the week experiences the fewest flight delays on this route?
Saturday tends to have the lowest number of delays on this route, whereas Monday has historically faced a higher average of delays compared to other days of the week.
Which airline has the best punctuality record on St. Louis to San Juan flights?
Over the last year, Southwest have had the lowest number of delays on this route, with just 20% of flights being delayed.
Reviews of airlines servicing San Juan
Get insights into the airlines that provide service to San Juan. 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 San Juan. Reviews last updated March 11, 2026.
Peruse reviews from past customers who have flown with Southwest,Delta, andUnited Airlines from St. Louis to San Juan to help guide your decision. You can also see how each airline stacks up in terms of entertainment options, comfort, food, crew/service, and boarding process.
Comfort
8.0
Overall
8.0
Entertainment
7.5
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Overall
8.0
Entertainment
7.5
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Overall
8.0
Entertainment
7.5
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Overall
8.0
Entertainment
7.5
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Overall
8.0
Entertainment
7.5
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Comfort
8.0
Overall
8.0
Entertainment
7.5
Food
7.0
Boarding
8.1
Crew
8.6
Reviews
1 / 20
10.0
ExcellentAnonymous,Mar 2026
KOA - HNL
Related info for your journey
Find useful and relevant information for your journey from St. Louis to San Juan. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
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Alternative routes for St. Louis to San Juan
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Complete your trip
Complete your trip to San Juan by adding a car rental and/or hotel reservation to your travel itinerary.
Search flights from St. Louis to San Juan by cabin class
Find flights from St. Louis to San Juan, based on your preferred cabin class, be it economy, premium economy, business, or first class.
St. Louis and San Juan flights
Browse other St. Louis and San Juan flight options. Last updated on March 11, 2026.
Other flights from St. Louis
Browse through other flights departing from St. Louis. Flights are based on user searches made on Cheapflights and were last updated on March 11, 2026.
Popular flight searches
Check out other popular destinations found by fellow travelers in 2026
Top 6 airlines flying from St. Louis to San Juan
Discover the top 6 airlines that operate flights from St. Louis to San Juan. 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 March 11, 2026.
| Airline | Cheapest | Average | Flexibility | On-time |
|---|---|---|---|---|
| Cheapest$138 | Average$322 | FlexibilityNo cancel fee | On-time62% | |
| Cheapest$146 | Average$334 | FlexibilityNo cancel fee | On-time65% | |
| Cheapest$156 | Average$387 | FlexibilityNo cancel fee | On-timeN/A | |
| Cheapest$219 | Average$525 | FlexibilityNo cancel fee | On-time63% | |
| Cheapest$225 | Average$371 | FlexibilityNo cancel fee | On-time69% | |
| Cheapest$231 | Average$518 | FlexibilityNo cancel fee | On-time71% |