HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Keflavik Intl

$1,199+ Cheap flights from Islip, NY (ISP) to Keflavik Intl (KEF)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 12/15. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — KEF
Jan 11 — Jan 181
Sun 1/11
Sun 1/18
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Islip to Keflavik Intl 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

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

Cheap flight deals from Islip to Keflavik Intl

Cheapest flights from Islip to Keflavik Intl
Explore the most affordable flight options available from Islip to Keflavik Intl. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 12, 2025.

This Kiwi.com deal was found by Cheapflights users on 12/11. 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.
Mon 12/152:25 pmISP - KEF
1 stop11h 15mMultiple Airlines
Wed 12/174:45 pmKEF - ISP
2 stops23h 40mMultiple Airlines
Deal found 12/11$1,199
This Kiwi.com deal was found by Cheapflights users on 12/11. 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.
Wed 12/176:00 amISP - KEF
1 stop19h 15mMultiple Airlines
Sat 12/205:00 pmKEF - ISP
2 stops25h 09mMultiple Airlines
Deal found 12/11$1,283
This Kiwi.com deal was found by Cheapflights users on 12/11. 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 12/2512:30 pmISP - KEF
1 stop12h 35mMultiple Airlines
Sun 12/285:00 pmKEF - ISP
1 stop23h 05mMultiple Airlines
Deal found 12/11$1,497

Find flight deals from Islip to Keflavik Intl

Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) to Keflavik Intl (KEF). 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 December 12, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$1,497
(Kiwi.com)

Popular in

December

Cheapest in

May

Average price

$693
Provider with most accurate pricing for Islip Long Island-Reykjavik Keflavik Intl flight deals.
Search Deals
Provider most trusted by Cheapflights users for Islip Long Island-Reykjavik Keflavik Intl flights.
Search Deals
From Islip Long Island to Reykjavik Keflavik Intl
Search Deals
Highest demand for flights based on searches. 10% potential increase in price ($55 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 4% potential price decrease ($22 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in December 2025
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Islip to Keflavik Intl 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 December 12, 2025.
Use the filters below to find and compare flights from Islip to Reykjavik Keflavik Intl Airport that are best for you.

Fly from

Islip

Fly to

Keflavik Intl

Route

Depart

Return

Price

IslipReykjavik

ISP - KEF

ISPKEF

Islip Long Island

Thu 12/25

12:30 pm-6:05 am

1 stop12h 35m

Reykjavik Keflavik Intl

Sun 12/28

5:00 pm-11:05 am

1 stop23h 05m

$1,497

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/11

Compare providers for flights from Islip to Keflavik Intl

Provider information is updated monthly. Please note that these providers often have deals for this flight, but the availability may vary on a day-by-day basis on Cheapflights.
Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Islip to Keflavik Intl in December.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

  • Most accurate provider: When it comes to deals on Islip, New York-Reykjavik Keflavik Intl Airport flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Islip, New York-Reykjavik Keflavik Intl Airport flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Islip, New York-Reykjavik Keflavik Intl Airport flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Islip, New York-Reykjavik Keflavik Intl Airport flights, Cheapflights users trust eDreams the most. eDreams has received a user feedback score of 3 out of 3 stars (3 being the best), meaning they have been trusted the most by Cheapflights users looking for Islip, New York-Reykjavik Keflavik Intl Airport flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

Best time to book a flight from Islip to Keflavik Intl

Have a flexible travel schedule? Discover the best time to fly to Keflavik Intl 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 Reykjavik Keflavik Intl Airport

What is the cheapest month to book a flight from Islip, New York to Reykjavik Keflavik Intl Airport?

Currently, March is the cheapest month in which you can book a flight from Islip, New York to Reykjavik Keflavik Intl Airport (average of $221). Flying from Islip, New York to Reykjavik Keflavik Intl Airport in August is currently the most expensive (average of $330). 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.

Related info for your journey

Find useful and relevant information for your journey from Islip to Keflavik Intl. 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 Reykjavik Keflavik Intl?

    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 Reykjavik Keflavik Intl. 0 airlines have flights from Long Island to Reykjavik Keflavik Intl on a regular basis. Booking flights from Islip Long Island to Reykjavik Keflavik Intl should not be difficult; the airport handles an average of 0 outbound flights to Reykjavik Keflavik Intl per day.

  • Can I find deals for flights from Islip to Keflavik Intl that include hotel bookings?

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

  • How can I find direct flights from Islip to Keflavik Intl?

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

  • Can I find deals for business class flights from Islip to Keflavik Intl?

    Yes. Cheapflights offers flight deals from Islip to Keflavik Intl 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 Reykjavik Keflavik Intl Airport?

    Currently, March is the cheapest month in which you can book a flight from Islip, New York to Reykjavik Keflavik Intl Airport (average of $221). Flying from Islip, New York to Reykjavik Keflavik Intl Airport in August is currently the most expensive (average of $330). 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

Traveling to a place near Reykjavik Keflavik Intl Airport?

Book flights to Reykjavik Keflavik Intl Airport if you plan to visit one of these locations
Keflavik
Hveragerdi

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.

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.
Site
©2025 Cheapflights