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Islip

$381+ Cheap flights from Seattle to Islip (SEA - ISP)

This is the cheapest one-way flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 11/2. Fares are subject to change and may not be available on all flights or dates of travel.
SEA — ISP
Oct 11 — Oct 181
Sat 10/11
Sat 10/18
1 adult, Economy
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Cheap 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 September 11, 2025.

Round-trip from

$423
(Southwest)

One-way from

$381
(Cheapflightsfares)

Popular in

December

Cheapest in

September

Average price

$312
From Seattle/Tacoma Intl to Islip Long Island
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One-way flight from Seattle/Tacoma Intl to Islip Long Island
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Highest demand for flights based on searches. 3% potential increase in price ($15 potential increase over avg. RT price).
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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 September 2025
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Find 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 September 11, 2025.

This Southwest deal was found by Cheapflights users on 9/9. 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.
Wed 11/268:40 amSEA - ISP
2 stops12h 15mSouthwest
Wed 12/312:55 pmISP - SEA
2 stops13h 00mSouthwest
Deal found 9/9$423
This Cheapflightsfares deal was found by Cheapflights users on 9/9. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/168:00 amSEA - ISP
1 stop9h 01mMultiple Airlines
Tue 9/234:33 pmISP - SEA
1 stop8h 35mMultiple Airlines
Deal found 9/9$687
This Cheapflightsfares deal was found by Cheapflights users on 9/10. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 9/1711:34 pmSEA - ISP
1 stop8h 24mMultiple Airlines
Sat 9/204:33 pmISP - SEA
1 stop8h 35mMultiple Airlines
Deal found 9/10$710
This Cheapflightsfares deal was found by Cheapflights users on 9/10. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 9/138:00 amSEA - ISP
1 stop9h 01mMultiple Airlines
Sat 9/204:33 pmISP - SEA
1 stop8h 35mMultiple Airlines
Deal found 9/10$745
This Cheapflightsfares deal was found by Cheapflights users on 9/11. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/2111:34 pmSEA - ISP
1 stop8h 24mMultiple Airlines
Fri 9/264:33 pmISP - SEA
1 stop8h 35mMultiple Airlines
Deal found 9/11$748
This Cheapflightsfares deal was found by Cheapflights users on 9/9. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/1511:34 pmSEA - ISP
1 stop8h 24mMultiple Airlines
Tue 9/164:33 pmISP - SEA
1 stop8h 35mMultiple Airlines
Deal found 9/9$762
This Cheapflightsfares deal was found by Cheapflights users on 9/10. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/1411:34 pmSEA - ISP
1 stop8h 24mMultiple Airlines
Tue 9/164:33 pmISP - SEA
1 stop8h 35mMultiple Airlines
Deal found 9/10$766
This Cheapflightsfares deal was found by Cheapflights users on 9/10. 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 Cheapflightsfares is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/1511:34 pmSEA - ISP
1 stop8h 24mMultiple Airlines
Mon 9/224:33 pmISP - SEA
1 stop8h 35mMultiple Airlines
Deal found 9/10$797

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 September 11, 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

Tue 11/25

8:40 am-11:55 pm

2 stops12h 15m

Islip Long Island

Tue 12/2

12:55 pm-10:30 pm

2 stops12h 35m

$423

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Wed 11/26

8:40 am-11:55 pm

2 stops12h 15m

Islip Long Island

Tue 12/2

12:55 pm-10:30 pm

2 stops12h 35m

$423

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Wed 11/26

8:40 am-11:55 pm

2 stops12h 15m

Islip Long Island

Wed 12/3

12:55 pm-10:55 pm

2 stops13h 00m

$423

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Sun 9/21

11:34 pm-10:58 am

1 stop8h 24m

Islip Long Island

Fri 9/26

2:19 pm-10:29 pm

2 stops11h 10m

$752

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Wed 11/26

11:25 pm-10:58 am

1 stop8h 33m

Islip Long Island

Wed 12/3

5:54 pm-7:18 pm

2 stops28h 24m

$830

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Wed 11/26

11:25 pm-10:58 am

1 stop8h 33m

Islip Long Island

Tue 12/2

11:08 am-7:18 pm

2 stops35h 10m

$838

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Fri 12/12

11:21 pm-10:58 am

1 stop8h 37m

Islip Long Island

Mon 1/5

2:19 pm-11:15 pm

2 stops11h 56m

$845

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Thu 12/11

9:00 am-8:01 pm

1 stop8h 01m

Islip Long Island

Mon 1/5

2:19 pm-11:15 pm

2 stops11h 56m

$845

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Sun 10/19

11:15 pm-10:58 am

1 stop8h 43m

Islip Long Island

Thu 10/23

2:19 pm-11:04 pm

2 stops11h 45m

$883

SeattleIslip

SEA - ISP

SEAISP

Seattle/Tacoma Intl

Thu 12/4

11:21 pm-10:58 am

1 stop8h 37m

Islip Long Island

Mon 12/8

2:19 pm-10:43 pm

2 stops11h 24m

$902

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/9

Showing 1-10 of 20 results
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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?

Currently, January is the cheapest month in which you can book a flight from Seattle to Islip (average of $108). Flying from Seattle to Islip in November is currently the most expensive (average of $213). 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.

  • How long is the flight from Seattle to Islip?

    Southwest can get you from Seattle to Islip in just under 12h 15m. Your travel time can differ by up to . The distance between Seattle and Islip is about 2440 mi.

  • 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?

    Currently, January is the cheapest month in which you can book a flight from Seattle to Islip (average of $108). Flying from Seattle to Islip in November is currently the most expensive (average of $213). 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
Southampton

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