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Islip

$904+ Cheap flights from Seattle to Islip, NY (SEA - ISP)

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 1/8. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ISP
ene. 11 — ene. 181
dom. 1/11
dom. 1/18
1 adult, Economy
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Cheap flight deals from Seattle to Islip

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

This Southwest 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/159:35 amSEA - ISP
2 stops9h 30mSouthwest
mié. 12/1712:55 pmISP - SEA
2 stops13h 00mSouthwest
Deal found 12/11$1,087
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 12/1511:10 pmSEA - ISP
1 stop14h 00mMultiple Airlines
mié. 12/1712:30 pmISP - SEA
2 stops14h 42mMultiple Airlines
Deal found 12/11$1,436
This Expedia 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
sáb. 12/2711:25 pmSEA - ISP
1 stop8h 40mMultiple Airlines
mié. 12/3112:30 pmISP - SEA
2 stops23h 47mMultiple Airlines
Deal found 12/11$1,542

Find flight deals from Seattle to Islip

Discover tips and strategies to find the most affordable flight options for your journey from Seattle (SEA) to Islip (ISP). 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 diciembre 12, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$904
(Expedia)

Popular in

December

Cheapest in

September

Average price

$492
Provider with most accurate pricing for Seattle/Tacoma Intl-Islip Long Island flight deals.
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Provider most trusted by Cheapflights users for Seattle/Tacoma Intl-Islip Long Island flights.
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From Seattle/Tacoma Intl to Islip Long Island
Search Deals
Highest demand for flights based on searches. 6% potential increase in price ($26 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($11 potential savings vs. average RT price).
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Average for round-trip flights in December 2025
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Cheapflights Fare Finder

 
Customize your flight search to find flights from Seattle to Islip 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 diciembre 12, 2025.
Use the filters below to find and compare flights from Seattle to Islip that are best for you.

Fly from

Seattle

Fly to

Islip

Route

Depart

Return

Price

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

jue. 1/8

7:55 am-7:45 pm

1 stop8h 50m

Islip Long Island

jue. 1/15

12:30 pm-10:17 pm

1 stop12h 47m

$904

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

mié. 3/4

10:40 pm-4:10 pm

1 stop14h 30m

Islip Long Island

dom. 3/8

7:25 am-10:18 pm

2 stops17h 53m

$970

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

vie. 2/20

10:40 pm-11:05 am

1 stop9h 25m

Islip Long Island

lun. 2/23

12:30 pm-10:00 pm

1 stop12h 30m

$979

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

sáb. 12/27

11:25 pm-11:05 am

1 stop8h 40m

Islip Long Island

mié. 12/31

12:30 pm-9:17 am

2 stops23h 47m

$1,542

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/11

Compare providers for flights from Seattle to Islip

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 Seattle to Islip in December.
ProviderPrice AccuracyTrust Score*
eDreamsPrice Accuracy3 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star

*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 Seattle-Islip, New York flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Seattle-Islip, New York flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Seattle-Islip, New York flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Seattle-Islip, New York 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 Seattle-Islip, New York 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 Seattle to Islip

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

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

Currently, December is the cheapest month in which you can book a flight from Seattle to Islip, New York (average of $129). Flying from Seattle to Islip, New York in January is currently the most expensive (average of $217). 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 Seattle to Islip. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

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

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

  • How can I find direct flights from Seattle to Islip?

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

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

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

    Currently, December is the cheapest month in which you can book a flight from Seattle to Islip, New York (average of $129). Flying from Seattle to Islip, New York in January is currently the most expensive (average of $217). 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 Islip?

Book flights to Islip if you plan to visit one of these locations
Riverhead

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