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Flights from Islip to San Juan

Find the cheapest flight options from Islip to San Juan over the next three months. Book one-way tickets from CAD 124 and round-trip tickets from CAD 379.

      • ISP 15:34
        10h 16m
        1 stop
        SJU 02:50
        Islip - San Juan | Sun, Jan 11 | Frontier Airlines
        SJU 06:00
        6h 35m
        1 stop
        ISP 11:35
        San Juan - Islip | Wed, Jan 14 | Jetblue Airways
        CAD 379 CAD 705
        46% OFF
        46% OFF
        CAD 705 CAD 379
      • ISP 19:43
        13h 41m
        1 stop
        SJU 10:24
        Islip - San Juan | Thu, Jan 22 | Frontier Airlines
        SJU 06:01
        6h 32m
        1 stop
        ISP 11:33
        San Juan - Islip | Thu, Jan 29 | Jetblue Airways
        CAD 383 CAD 705
        46% OFF
        46% OFF
        CAD 705 CAD 383
      • ISP 06:00
        8h 31m
        1 stop
        SJU 15:31
        Islip - San Juan | Thu, Dec 18 | Frontier Airlines
        SJU 06:00
        19h 55m
        1 stop
        ISP 00:55
        San Juan - Islip | Mon, Dec 22 | Frontier Airlines
        CAD 388 CAD 705
        45% OFF
        45% OFF
        CAD 705 CAD 388
      • ISP 19:58
        23h 31m
        1 stop
        SJU 20:29
        Islip - San Juan | Thu, Jan 15 | Frontier Airlines
        SJU 03:58
        19h 48m
        1 stop
        ISP 22:46
        San Juan - Islip | Sat, Jan 17 | Frontier Airlines
        CAD 419
        41% OFF
        CAD 705 CAD 419
      • ISP 10:19
        15h 31m
        1 stop
        SJU 02:50
        Islip - San Juan | Sat, Dec 13 | Frontier Airlines
        SJU 03:55
        19h 49m
        1 stop
        ISP 22:44
        San Juan - Islip | Wed, Dec 17 | Frontier Airlines
        CAD 420
        41% OFF
        CAD 705 CAD 420
      • ISP 20:29
        12h 26m
        1 stop
        SJU 09:55
        Islip - San Juan | Fri, Dec 12 | Frontier Airlines
        SJU 03:55
        21h 43m
        1 stop
        ISP 00:38
        San Juan - Islip | Wed, Dec 17 | Frontier Airlines
        CAD 420
        40% OFF
        CAD 705 CAD 420
      • ISP 12:25
        6h 37m
        1 stop
        SJU 20:02
        Islip - San Juan | Tue, Jan 13 | Jetblue Airways
        SJU 16:36
        27h 12m
        1 stop
        ISP 18:48
        San Juan - Islip | Wed, Jan 21 | Frontier Airlines
        CAD 462
        34% OFF
        CAD 705 CAD 462
      • ISP 09:40
        16h 10m
        1 stop
        SJU 02:50
        Islip - San Juan | Sun, Jan 11 | Jetblue Airways
        SJU 06:00
        6h 35m
        1 stop
        ISP 11:35
        San Juan - Islip | Wed, Jan 14 | Jetblue Airways
        CAD 478
        32% OFF
        CAD 705 CAD 478
      • ISP 06:00
        16h 56m
        1 stop
        SJU 23:56
        Islip - San Juan | Mon, Dec 15 | Frontier Airlines
        SJU 03:55
        9h 47m
        1 stop
        ISP 12:42
        San Juan - Islip | Fri, Dec 19 | Frontier Airlines
        CAD 504
        28% OFF
        CAD 705 CAD 504
      • ISP 09:40
        13h 19m
        1 stop
        SJU 23:59
        Islip - San Juan | Sat, Jan 31 | Jetblue Airways
        SJU 16:36
        17h 19m
        1 stop
        ISP 08:55
        San Juan - Islip | Wed, Feb 4 | Frontier Airlines
        CAD 515
        27% OFF
        CAD 705 CAD 515
      • ISP 13:00
        17h 25m
        1 stop
        SJU Invalid Date
        Islip - San Juan | Sun, Dec 14 | Normal Airline
        SJU 15:00
        6h
        Direct
        ISP 16:00
        San Juan - Islip | Tue, Dec 16 | Normal Airline
        Find More Flights
        Find More Flights
      • ISP 08:00
        7h 27m
        1 stop
        SJU 16:27
        Islip - San Juan | Tue, Jan 13 | Frontier Airlines
        CAD 124 CAD 298
        59% OFF
        59% OFF
        CAD 298 CAD 124
      • ISP 19:58
        12h 27m
        1 stop
        SJU 09:25
        Islip - San Juan | Sun, Jan 18 | Frontier Airlines
        CAD 135 CAD 298
        55% OFF
        55% OFF
        CAD 298 CAD 135
      • ISP 19:43
        13h 41m
        1 stop
        SJU 10:24
        Islip - San Juan | Thu, Jan 22 | Frontier Airlines
        CAD 169 CAD 298
        43% OFF
        43% OFF
        CAD 298 CAD 169
      • ISP 20:54
        17h 32m
        1 stop
        SJU 15:26
        Islip - San Juan | Mon, Jan 19 | Frontier Airlines
        CAD 170
        43% OFF
        CAD 298 CAD 170
      • ISP 19:43
        18h 43m
        1 stop
        SJU 15:26
        Islip - San Juan | Mon, Jan 26 | Frontier Airlines
        CAD 178
        40% OFF
        CAD 298 CAD 178
      • ISP 16:40
        16h 36m
        1 stop
        SJU 10:16
        Islip - San Juan | Mon, Jan 5 | Frontier Airlines
        CAD 194
        35% OFF
        CAD 298 CAD 194
      • ISP 12:25
        11h 55m
        1 stop
        SJU 01:20
        Islip - San Juan | Sun, Jan 18 | Jetblue Airways
        CAD 199
        33% OFF
        CAD 298 CAD 199
      • ISP 13:10
        9h 34m
        1 stop
        SJU 23:44
        Islip - San Juan | Tue, Jan 6 | Jetblue Airways
        CAD 211
        28% OFF
        CAD 298 CAD 211
      • ISP 12:25
        22h 30m
        1 stop
        SJU 11:55
        Islip - San Juan | Thu, Jan 22 | Jetblue Airways
        CAD 215
        28% OFF
        CAD 298 CAD 215
      • ISP 15:34
        10h 14m
        1 stop
        SJU 02:48
        Islip - San Juan | Thu, Jan 15 | Frontier Airlines
        CAD 218
        27% OFF
        CAD 298 CAD 218
      • ISP 13:00
        17h 25m
        1 stop
        SJU Invalid Date
        Islip - San Juan | Sun, Dec 14 | Normal Airline
        Find More Flights
        Find More Flights

Displayed flight fares from Islip to San Juan are based on average prices across airlines for the next 3 months, according to the latest Trip.com database.

Flight details for Islip to San Juan

The distance between Islip and San Juan is 2,575.4 km. Based on Trip.com's data, travel demand peaks in July. The off-season for travel is September.

Cheapest one-way flight priceCAD 124
Cheapest round-trip ticket priceCAD 379
Off-season for travelSeptember
Peak season for travelJuly
Flight distance2,575.4 km

Find the best time to fly from Islip to San Juan

The cheapest time for Islip to San Juan flights: Jan 11 to Jan 18 — one way flight prices from CAD 123.

Cheapest flights
From price
Search
  • 714
  • 1421
  • 2128

  • Jan

    284
  • 411
  • 1118
  • 1825

  • Feb

    251
  • 18
  • 815
  • 1522

  • Mar

    221
Displayed fare trends are based on Trip.com's aggregated average of the lowest flight prices from Islip to San Juan, calculated over the upcoming 10 weeks.

Flight FAQs

  • What are the cheapest flights from Islip to San Juan (ISP-SJU)?

    Based on Trip.com data, Frontier Airlines offers one-way fares as low as CAD 124 on Cheapest nonstop routes (e.g. ISP to SJU on Tue, Jan 13), while Frontier Airlines offers Cheapest nonstop round-trips from CAD 379 departing on Sun, Jan 11 and returning on Wed, Jan 14.
  • By analyzing data from all airlines on the Trip.com flight calendar, it looks like the best time to book a flight from Islip to San Juan is around 40 days (6 weeks) in advance, and the best time to fly is usually on Tuesday, Wednesday, and Saturday. Tuesday typically offers the cheapest flights for departure, while Saturday offers the best return deals.
  • To find best deals on flights from Islip to San Juan, you can use various tools on Trip.com:
    · Be flexible with your travel dates to get the cheapest flight deal. Now the cheapest flight deal is on Tue, Jan 13, with one-way flights priced at just CAD 124.
    · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is Frontier Airlines.
    · Set up price alerts to easily monitor ticket prices without having to check every day.
    · Check Trip.com flight deals and promo codes frequently.
    · Avoid peak season unless you book very early. It seems the peak season for San Juan travel is around July.
    · Get exclusive promo codes for Trip.com app users.
  • The cheapest months to fly from Islip to San Juan is September, when demand for travel is lower.
  • After crunching the numbers on our December flight calendar, it's currently cheapest to fly from Islip to San Juan on December 18, 2025 with Frontier Airlines, with prices starting at CAD 387.
  • The time difference between San Juan and Islip is 1h.
  • Tickets can only be changed or canceled if permitted by airline policy. To submit a change or cancellation request, go to the flight bookings page, select the option to change or cancel your booking, choose the relevant passengers and segment, and submit a request. Please note that additional charges may apply according to the airline ticket policy. However, if the flight has been rescheduled and you would like to change or cancel your ticket, you can submit an involuntary cancellation request. For more details about change and cancellation policies, please check the customer support pages.