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Flights from Islip to Lisbon

Find flight deals from Islip to Lisbon for the next 3 months. Book one way flights from €798 or round trip flights from €2,807.

      • ISP 9:59 AM
        17h 1m
        1 stop
        LIS 8:00 AM
        Islip - Lisbon | Sat, Dec 27 | Cape Air
        LIS 11:15 AM
        13h 30m
        1 stop
        ISP 7:45 PM
        Lisbon - Islip | Sat, Jan 3 | Delta Air Lines
        €2,807 €3,153
        11% OFF
        11% OFF
        €3,153 €2,807
      • ISP 1:00 PM
        17h 25m
        1 stop
        LIS Invalid Date
        Islip - Lisbon | Fri, Dec 12 | Normal Airline
        LIS 3:00 PM
        6h
        Nonstop
        ISP 4:00 PM
        Lisbon - Islip | Sun, Dec 14 | Normal Airline
        Find More Flights
        Find More Flights

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

Flight Info | Islip to Lisbon

The distance between Islip and Lisbon is approximately 5,345.23 km. Based on Trip.com's data travel demand peaks in November. The off-season for travel is October.

Cheapest one-way flight price€798
Cheapest round-trip ticket price€2,807
Off-season for travelOctober
Peak season for travelNovember
Flight distance5,345.23 km

When is the cheapest time to fly from Islip to Lisbon?

The cheapest time for Islip to Lisbon flights: Jan 4 to Jan 11 — one way flight prices from €269.

Cheapest flights
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  • 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 Lisbon, calculated over the upcoming 10 weeks.

Frequently Asked Questions

  • What are the cheapest flights from Islip to Lisbon (ISP-LIS)?

    Based on Trip.com data, Cape Air offers one-way fares as low as €798 on Cheapest nonstop routes (e.g. ISP to LIS on Fri, Dec 12), while Cape Air offers Cheapest nonstop round-trips from €2,807 departing on Sat, Dec 27 and returning on Sat, Jan 3.
  • 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 Lisbon 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 Lisbon, 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 Fri, Dec 12, with one-way flights priced at just €798.
    · Compare airlines strategically. Budget carriers often provide the lowest base fares, while we found the most affordable airline currently operating on this route is Cape Air.
    · 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 Lisbon travel is around November.
    · Get exclusive promo codes for Trip.com app users.
  • The cheapest months to fly from Islip to Lisbon is October, when demand for travel is lower.
  • After crunching the numbers on our December flight calendar, it's currently cheapest to fly from Islip to Lisbon on December 27, 2025 with Cape Air, with prices starting at €2,806.
  • The time difference between Lisbon and Islip is 5h.
  • 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.

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