$126 Find Cheap Flights from Islip 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 Islip to Puerto Rico departing on 9/22. 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.
1 adult
1 adult, Economy

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Flight Deals

Book Cheap Islip 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 Islip 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 Islip to Puerto Rico

Sat, Sep 27 - Sat, Sep 27
Frontier Logo
5:05 pm - 11:59 pmISP-SJU
6h 54m1 stop
Frontier Logo
3:39 am - 10:40 amSJU-ISP
7h 01m1 stop
$245Frontier
Find Deal
Sat, Sep 27 - Sat, Sep 27
Frontier Logo
5:05 pm - 11:59 pmISP-SJU
6h 54m1 stop
Frontier Logo
3:39 am - 10:40 amSJU-ISP
7h 01m1 stop
$249Frontier
Find Deal
Fri, Sep 26 - Thu, Oct 2
Frontier Logo
5:05 pm - 11:59 pmISP-SJU
6h 54m1 stop
Frontier Logo
3:39 am - 10:40 amSJU-ISP
7h 01m1 stop
$250Frontier
Find Deal
Fri, Sep 26 - Sun, Sep 28
Frontier Logo
5:05 pm - 11:59 pmISP-SJU
6h 54m1 stop
Frontier Logo
3:39 am - 10:40 amSJU-ISP
7h 01m1 stop
$251Frontier
Find Deal
Sun, Sep 28 - Sun, Oct 5
Frontier Logo
5:12 pm - 3:22 pmISP-SJU
22h 10m1 stop
Frontier Logo
9:07 am - 10:40 amSJU-ISP
25h 33m1 stop
$254Frontier
Find Deal
Tue, Feb 3 - Tue, Feb 10
JetBlue Logo
1:15 pm - 9:52 pmISP-SJU
7h 37m1 stop
JetBlue Logo
6:00 am - 12:20 pmSJU-ISP
7h 20m1 stop
$403JetBlue
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Tue, Sep 30 - Fri, Oct 3
Multiple Airlines Logo
11:25 am - 1:58 amISP-SJU
14h 33m2 stops
Multiple Airlines Logo
3:39 am - 10:55 amSJU-ISP
7h 16m1 stop
$405Multiple Airlines
Find Deal
Mon, Jan 19 - Sun, Jan 25
JetBlue Logo
12:05 pm - 9:52 pmISP-SJU
8h 47m1 stop
JetBlue Logo
6:00 am - 12:40 pmSJU-ISP
7h 40m1 stop
$436JetBlue
Find Deal
Sat, Dec 6 - Mon, Dec 8
Multiple Airlines Logo
9:09 pm - 9:52 amISP-SJU
11h 43m1 stop
Multiple Airlines Logo
7:00 am - 8:07 pmSJU-ISP
14h 07m2 stops
$455Multiple Airlines
Find Deal
Sat, Dec 6 - Mon, Dec 8
Southwest Logo
1:30 pm - 12:15 amISP-SJU
9h 45m2 stops
Southwest Logo
5:45 am - 3:20 pmSJU-ISP
10h 35m2 stops
$472Southwest
Find Deal
Booking Insights

KAYAK's insights & trends for Islip to Puerto Rico flights

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

What is the cheapest month to fly from Islip to Puerto Rico?

To calculate monthly average prices, KAYAK takes all prices for each month over the last year for round-trip flights from Islip 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 Islip to Puerto Rico is November, when tickets cost $204 (return) on average. On the other hand, the most expensive months are October and December, when the average cost of round-trip tickets is $943 and $673 respectively.

Good to know

Low seasonJuly
Cheapest flight$126
Best time to beat the crowds with an average 20% drop in price.
Most popular time to fly and prices are also 35% lower on average.
Flight from Islip to San Juan

FAQs - booking Puerto Rico flights

  • How does KAYAK find such low prices on flights from Islip 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 Islip to Puerto Rico.

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

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight from Islip 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 Islip 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 Islip 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 Islip 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 Islip to Puerto Rico up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

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

    The cheapest time of day to fly to Puerto Rico is generally at night, when round-trip flights cost $208 on average. Morning departures are around 27% cheaper than evening flights, on average. The most expensive time of day to fly to Puerto Rico is generally in the evening, which is peak travel time and where the average cost of a ticket is $390.

Reviews of the top 3 airlines serving from Islip to Puerto Rico

 
Need help choosing which airline to fly with from Islip 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.
8.0
SouthwestOverall score based on 4242 reviews
8.1Boarding
8.6Crew
7.5Entertainment
7.0Food
8.0Comfort
Airline reviews

I wish they had movie screens in the headrests. The seats are much improved, more legroom and recently renovated. Bathroom was clean. Staff was outstanding!!

10.0 ExcellentG, Sep 2025LAS - ATL
Read more Southwest reviews

I wish they had movie screens in the headrests. The seats are much improved, more legroom and recently renovated. Bathroom was clean. Staff was outstanding!!

As always, the entire Southwest experience was wonderful, from online booking to flight to baggage retrieval. Very grateful.

The weather could have been better. There was a 40 minute ATC delay in SFO because of marine fog and a micro cell storm delayed landing and take-off at Nashville. The gate was changed 5 minutes from boarding from gate B3 to gate C23 at Nashville airport.

After being assaulted by a flight attendant I was then brushed off as oh well because he long braids didn’t mean to whip me in the eye. I have filed complaints and will see. But like any other issue I’ve had with kayak involved it’s been trash. Last time I’ll be using your app

AC sub par. WiFi not working correctly. Ac sucked. Seats very narrow.

Near 4 hour flight with only 1 service. Had to use call button to request water. Internet and power not working until into flight. Internet would stop working during flight.

Southwest's seats are the least comfortable I have ever sat in.

The cabin was quiet for the redeye flight. The area was clean. The staff was great. The 787 Max was in good condition. Drawbacks were that the seat widths were tight for some passengers. The seat padding was at best average and for a long flight uncomfortable.

Southwest like most American domestic airlines, is a mediocre airline. But it is among the cheapest. Oh well.

My flight was delayed 50 minutes and we were rushed to board to then sit for 15 minutes until the pilot arrived. Unacceptable since we could have waited to board. Also the delayed flight was updated AFTER we boarded to more than the 10 minutes as originally stated.

Worst flight experience ever flights canceled. JetBlue told us just did not even bother standing in line to come back in one and a half hours then without any information we had to go pick up all of our luggage and spend over $2000 in accommodation just to get home. JetBlue said that the next flight available for us to get home would be three days later. Absolutely absurd hasn’t offered to give us any compensation do not fly JetBlue horrible company. They said it was based on the weather and the weather is great in all locations that we would’ve been flying to total hoax. I think it’s a conspiracy theory.

flight was delayed for hours with no explanation. The plane was a very old aircraft.

Communication since no reason or explanation was given for 3 hrs delay

The flight departed more than 1 hour late. Leg room is bigger than most airlines

Excellent. Although they used to greet me as a mosaic member and provide a free drink, early boarding helps me to keep coming back to JetBlue.

No music app working: no economy meal on five hour flight; hour on tarmac at the end waiting for a gate. Flight itself was smooth and easy.

Communication with the customer and stay is important. Staff off with a minor inconvenience but it worked out of course. Also this was a very old Mint Class plane. They snuck this one in on us. The updated aircraft are much better.

The flight itself was fine, but the boarding process was extremely frustrating. There is no one scanning boarding passes - passengers just scan themselves and enter the jetway. By the time my husband and I got on the plane and were halfway to our seats they determined there were too many bags on the plane and everything at that point needed to be checked. This created a lot of unnecessary chaos. They should have alerted people before getting on the plane that they would need to start checking bags instead of waiting until people were already on the plane.

The best flight I’ve had in a while. The plane was like 25% capacity, if that. Smoothest boarding and deplaning process I’ve ever experienced. Wish all flights were this smooth.

In flight on demand didn't work at our seats. Only a single beverage/snack run.

Seats were new and comfortable. Staff was fine. Missed my connection due to weather -which wasn’t their fault- but got no help at all. Gate staff sent me to customer service, which was and stayed unstaffed. Sign with QR code directed me to call or chat. Chat was useless. Call was returned after an hour. No itinerary offered by Frontier could get me home in less than 30 hours. Rebooked with another airline and got a partial refund that came to about 10 percent of what I paid to get home.

Finally a Frontier on time and efficient. I've had problems before with your airline, but this time everything went fine.

The experience was good. No frills but I got there safe and sound and on time.

Great for the price. No wifi or entertainment, but gate agents and crew were fantastic and we boarded quickly and left on time.

sluggish boarding and arrival procedures, fake nice flight attendants, and lots of delays.

Disaster. They lied every step of the way. We ended up being delayed due to crew and then allegedly abandoned the flight because of a curfew at LGA. No rebooking to LGA at any reasonable time. No hotel. No meal vouchers. Had to sleep in the airport and fly to Newark instead. Will never fly Frontier again.

What I expected, nickeled and dined and a frontier flight attendant loudly complained about her job and lack of communication as she headed to the gate on her cell phone. Not professional.

As every law enforcement agency I could imagine surrounded the plane and we didn’t disembark for 2 hours and then had to stick around for another hour to go get our personal belongings after leaving them behind and being bused away from the plane, it was scary and inconvenient. We were given no information as to why this was happening. Lack of communication with passengers was disappointing.

After boarding and un-boarding twice over 6+hours, the flight was canceled.

Severe turbulence. Captain never came on to reassure passengers after things settled down.

Everything you need to know for your flight from Islip to Puerto Rico

Information on your arrival and departure airports

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