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San Juan

$148+ Cheap flights from Islip, NY (ISP) 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 9/2. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — SJU
Jun 17 — Jun 241
Wed 6/17
Wed 6/24
1 adult, Economy
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Cheap flight deals from Islip to San Juan

Cheapest flights from Islip to San Juan
Explore the most affordable flight options available from Islip to San Juan. Find the lowest fares from popular airlines and budget airlines, with prices last updated on May 18, 2026.

This Frontier deal was found by Cheapflights users on 5/13. 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.
Thu 10/14:13 pm
ISP
-
SJU
1 stop9h 37m
Frontier
Mon 10/53:00 am
SJU
-
ISP
1 stop6h 33m
Frontier
Deal found 5/13$306
This CheapOair deal was found by Cheapflights users on 5/15. 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 9/124:13 pm
ISP
-
SJU
1 stop9h 37m
Frontier
Tue 9/153:00 am
SJU
-
ISP
1 stop6h 33m
Frontier
Deal found 5/15$310
This Priceline deal was found by Cheapflights users on 5/13. 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 7/3010:48 am
ISP
-
SJU
1 stop15h 23m
Frontier
Fri 8/149:24 am
SJU
-
ISP
1 stop24h 34m
Frontier
Deal found 5/13$316
This CheapOair deal was found by Cheapflights users on 5/16. 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 8/87:50 pm
ISP
-
SJU
1 stop28h 51m
Frontier
Fri 8/143:06 am
SJU
-
ISP
1 stop6h 52m
Frontier
Deal found 5/16$324
This CheapOair deal was found by Cheapflights users on 5/17. 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.
Fri 7/317:50 pm
ISP
-
SJU
1 stop28h 51m
Frontier
Fri 8/73:06 am
SJU
-
ISP
1 stop6h 52m
Frontier
Deal found 5/17$330
This CheapOair deal was found by Cheapflights users on 5/15. 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 7/227:50 pm
ISP
-
SJU
1 stop28h 51m
Frontier
Sun 7/265:22 pm
SJU
-
ISP
1 stop25h 41m
Frontier
Deal found 5/15$336
This CheapOair deal was found by Cheapflights users on 5/16. 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.
Fri 9/187:46 pm
ISP
-
SJU
1 stop28h 11m
Frontier
Sat 9/266:42 pm
SJU
-
ISP
1 stop14h 51m
Frontier
Deal found 5/16$350
This CheapOair deal was found by Cheapflights users on 5/17. 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.
Sun 8/210:48 am
ISP
-
SJU
1 stop15h 23m
Frontier
Fri 8/76:00 am
SJU
-
ISP
1 stop27h 58m
Frontier
Deal found 5/17$356
This Trip.com deal was found by Cheapflights users on 5/13. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 6/56:43 pm
ISP
-
SJU
1 stop29h 16m
Frontier
Wed 6/106:00 am
SJU
-
ISP
1 stop14h 57m
Frontier
Deal found 5/13$365
This CheapOair deal was found by Cheapflights users on 5/15. 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 5/266:02 pm
ISP
-
SJU
1 stop8h 06m
Frontier
Tue 6/95:15 pm
SJU
-
ISP
1 stop25h 50m
Frontier
Deal found 5/15$366
This CheapOair deal was found by Cheapflights users on 5/14. 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.
Thu 5/2811:00 am
ISP
-
SJU
1 stop15h 08m
Frontier
Sun 5/313:03 am
SJU
-
ISP
1 stop7h 02m
Frontier
Deal found 5/14$376
This Priceline deal was found by Cheapflights users on 5/16. 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 6/207:50 pm
ISP
-
SJU
1 stop28h 47m
Frontier
Wed 6/246:05 pm
SJU
-
ISP
1 stop26h 52m
Frontier
Deal found 5/16$379

Find flight deals from Islip to San Juan

Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) 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 May 18, 2026.

Round-trip from

$306
(Frontier)

One-way from

$148
(CheapOair)

Popular in

February

Cheapest in

January

Average price

$636
From Islip Long Island to San Juan
Search Deals
One-way flight from Islip Long Island to San Juan
Search Deals
Highest demand for flights based on searches. 9% potential increase in price ($55 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 6% potential price decrease ($32 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in May 2026
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Islip 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 May 18, 2026.
Use the filters below to find and compare flights from Islip to San Juan that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Fri 8/14

7:50 pm-12:41 am

1 stop28h 51m

San Juan Luis Munoz Marin Intl

Sun 8/16

3:06 am-9:58 am

1 stop6h 52m

$330

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Wed 7/1

9:52 pm-2:09 am

1 stop28h 17m

San Juan Luis Munoz Marin Intl

Mon 7/6

4:05 pm-3:56 pm

1 stop23h 51m

$426

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Sun 6/14

9:52 pm-5:21 pm

1 stop19h 29m

San Juan Luis Munoz Marin Intl

Sat 6/20

3:06 am-8:57 pm

1 stop17h 51m

$455
Quickest round-trip

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Tue 8/18

6:00 am-3:21 pm

1 stop9h 21m

San Juan Luis Munoz Marin Intl

Wed 8/19

3:01 pm-9:34 pm

1 stop6h 33m

$475

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Fri 6/26

9:52 pm-1:16 pm

1 stop15h 24m

San Juan Luis Munoz Marin Intl

Sat 6/27

3:06 am-8:57 pm

1 stop17h 51m

$475

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Wed 9/9

10:30 am-10:00 pm

2 stops11h 30m

San Juan Luis Munoz Marin Intl

Sun 9/20

6:35 am-3:55 pm

2 stops9h 20m

$508

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Sun 10/11

12:30 pm-8:35 pm

2 stops8h 05m

San Juan Luis Munoz Marin Intl

Wed 10/14

5:35 am-3:40 pm

2 stops10h 05m

$508

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Fri 6/12

9:52 pm-7:55 am

1 stop10h 03m

San Juan Luis Munoz Marin Intl

Mon 6/15

9:24 am-8:57 pm

1 stop11h 33m

$520

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Sun 6/21

3:07 pm-12:58 am

1 stop9h 51m

San Juan Luis Munoz Marin Intl

Tue 6/30

5:28 am-2:12 pm

1 stop8h 44m

$539
Cheapest one-way

IslipSan Juan

ISP - SJU

ISPSJU

Islip Long Island

Wed 9/2

10:48 am-11:29 pm

1 stop12h 41m

$148

Flights are sorted by cheapest round-trip flights first.

Deals found on 5/14

Showing 1-10 of 21 resultsSorted by cheapest first
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2
3

Best time to book a flight from Islip to San Juan

Have a flexible travel schedule? Discover the best time to fly to San Juan from Islip 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 Islip to San Juan

What is the cheapest month to book a flight from Islip, New York to San Juan?

Currently, January is the cheapest month in which you can book a flight from Islip, New York to San Juan (average of $106). Flying from Islip, New York to San Juan in February is currently the most expensive (average of $865). 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.

How much does it cost to fly round-trip from Islip, New York to San Juan?

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 May 18, 2026.
Peruse reviews from past customers who have flown with Southwest and Frontier from Islip 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.
Southwest
7.9
Good
4,288 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

7.9

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
7.9
Good
4,288 reviews
Southwest
7.9
Good
4,288 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

7.9

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Frontier
5.7
Fair
2,946 reviews
Southwest
7.9
Good
4,288 reviews

Crew

8.6

Comfort

8.0

Entertainment

7.5

Overall

7.9

Boarding

8.1

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from Islip to San Juan. 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 Islip to San Juan?

    Islip Long Island (ISP), located 7.2 mi from the city center, is the airport you fly out of when you book flights from Islip to San Juan. 2 airlines have flights from Long Island to San Juan on a regular basis. Booking flights from Islip Long Island to San Juan should not be difficult; the airport handles an average of 0 outbound flights to San Juan per day.

  • How long is the flight from Islip, New York to San Juan?

    Departing from Islip, New York to San Juan will take you 9h 21m. Airlines will cover a distance of 1599 mi. This flight may include one or multiple stops.

  • What are the cheapest airlines flying from Islip, New York to San Juan round-trip?

    Currently priced at $106, Frontier will fly you from Islip, New York to San Juan and back. In addition to Frontier, many other airlines offer competitively priced options for your trip. Check Cheapflights for deals on Southwest for as low as $367. Frontier is currently priced 79% below the average price you’ll pay for this route.

  • Can I find deals for flights from Islip to San Juan that include hotel bookings?

    Yes. In addition to deals on Islip to San Juan flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Islip to San Juan?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Islip to San Juan.

  • Can I find deals for business class flights from Islip to San Juan?

    Yes. Cheapflights offers flight deals from Islip to San Juan 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 Islip, New York to San Juan?

    Currently, January is the cheapest month in which you can book a flight from Islip, New York to San Juan (average of $106). Flying from Islip, New York to San Juan in February is currently the most expensive (average of $865). 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

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

Top 2 airlines flying from Islip to San Juan

Discover the top 2 airlines that operate flights from Islip 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 May 18, 2026.
AirlineCheapestAverageFlexibilityOn-time
FrontierCheapest$106Average$356FlexibilityNo cancel feeOn-time62%
SouthwestCheapest$367Average$556FlexibilityNo cancel feeOn-time63%

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