$239+ Cheap flights from Islip, NY to Seattle (ISP - SEA)
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 8/1. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — SEA
Jul 12 — Jul 191
Round-trip
1 adult, Economy
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Find cheap flights from Islip to Seattle 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
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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 Seattle
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Best
Last-minute
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Cheapest flights from Islip to SeattleExplore the most affordable flight options available from Islip to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2026.
Explore the most affordable flight options available from Islip to Seattle. Find the lowest fares from popular airlines and budget airlines, with prices last updated on June 12, 2026.
This Southwest deal was found by Cheapflights users on 6/8. 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.
Sat 8/2211:55 am
ISP
- SEA
2 stops14h 00m
Southwest
Fri 8/2810:30 pm
SEA
- ISP
1 stop13h 00m
Southwest
Deal found 6/8![Southwest logo]()
$405
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/410:20 am
ISP
- SEA
2 stops10h 15m
Southwest
Fri 9/1111:05 pm
SEA
- ISP
2 stops12h 25m
Southwest
Deal found 6/10![Southwest logo]()
$467
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/13:20 pm
ISP
- SEA
2 stops11h 05m
Southwest
Thu 9/310:30 pm
SEA
- ISP
1 stop8h 10m
Southwest
Deal found 6/10![Southwest logo]()
$476
This Southwest deal was found by Cheapflights users on 6/8. 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.
Sun 8/234:35 pm
ISP
- SEA
2 stops11h 15m
Southwest
Sun 8/3011:00 pm
SEA
- ISP
2 stops10h 35m
Southwest
Deal found 6/8![Southwest logo]()
$477
This Southwest deal was found by Cheapflights users on 6/9. 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.
Tue 7/74:40 pm
ISP
- SEA
2 stops10h 55m
Southwest
Tue 7/149:25 pm
SEA
- ISP
1 stop7h 40m
Southwest
Deal found 6/9![Southwest logo]()
$508
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/410:20 am
ISP
- SEA
1 stop7h 40m
Southwest
Fri 9/410:30 pm
SEA
- ISP
1 stop10h 35m
Southwest
Deal found 6/10![Southwest logo]()
$512
Best flights from Islip to SeattleDiscover carefully curated flight deals from Islip to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 12, 2026.
Discover carefully curated flight deals from Islip to Seattle that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated June 12, 2026.
This Southwest deal was found by Cheapflights users on 6/8. 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.
Sat 8/225:30 am
ISP
- SEA
1 stop8h 15m
Southwest
Fri 8/2810:30 pm
SEA
- ISP
1 stop13h 00m
Southwest
Deal found 6/8![Southwest logo]()
$452
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 9/410:20 am
ISP
- SEA
2 stops10h 15m
Southwest
Fri 9/1111:05 pm
SEA
- ISP
2 stops12h 25m
Southwest
Deal found 6/10![Southwest logo]()
$467
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 9/13:20 pm
ISP
- SEA
2 stops11h 05m
Southwest
Thu 9/310:30 pm
SEA
- ISP
1 stop8h 10m
Southwest
Deal found 6/10![Southwest logo]()
$476
This Southwest deal was found by Cheapflights users on 6/9. 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.
Fri 10/212:35 pm
ISP
- SEA
2 stops13h 10m
Southwest
Fri 10/912:15 am
SEA
- ISP
2 stops12h 20m
Southwest
Deal found 6/9![Southwest logo]()
$477
This Southwest deal was found by Cheapflights users on 6/8. 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.
Sun 8/234:35 pm
ISP
- SEA
2 stops11h 15m
Southwest
Sun 8/3011:00 pm
SEA
- ISP
2 stops10h 35m
Southwest
Deal found 6/8![Southwest logo]()
$477
This Southwest deal was found by Cheapflights users on 6/9. 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.
Tue 7/74:40 pm
ISP
- SEA
2 stops10h 55m
Southwest
Tue 7/149:25 pm
SEA
- ISP
1 stop7h 40m
Southwest
Deal found 6/9![Southwest logo]()
$508
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/812:25 pm
ISP
- SEA
2 stops10h 45m
Southwest
Wed 7/159:25 pm
SEA
- ISP
1 stop7h 55m
Southwest
Deal found 6/10![Southwest logo]()
$518
Last-minute flights from Islip to SeattleDiscover last-minute flight deals from Islip to Seattle. Data last updated June 12, 2026 and is based on user searches.
Discover last-minute flight deals from Islip to Seattle. Data last updated June 12, 2026 and is based on user searches.
This Southwest deal was found by Cheapflights users on 6/12. 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.
Thu 7/212:30 pm
ISP
- SEA
1 stop9h 00m
Southwest
Wed 7/89:25 pm
SEA
- ISP
1 stop7h 55m
Southwest
Deal found 6/12![Southwest logo]()
$623
This Southwest deal was found by Cheapflights users on 6/9. 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.
Sat 7/46:05 am
ISP
- SEA
1 stop10h 40m
Southwest
Fri 7/1010:45 pm
SEA
- ISP
2 stops9h 50m
Southwest
Deal found 6/9![Southwest logo]()
$568
This Southwest deal was found by Cheapflights users on 6/9. 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.
Tue 7/74:40 pm
ISP
- SEA
2 stops10h 55m
Southwest
Tue 7/149:25 pm
SEA
- ISP
1 stop7h 40m
Southwest
Deal found 6/9![Southwest logo]()
$508
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 7/812:25 pm
ISP
- SEA
2 stops10h 45m
Southwest
Wed 7/159:25 pm
SEA
- ISP
1 stop7h 55m
Southwest
Deal found 6/10![Southwest logo]()
$518
This Southwest deal was found by Cheapflights users on 6/10. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 7/912:30 pm
ISP
- SEA
2 stops12h 20m
Southwest
Thu 7/167:30 pm
SEA
- ISP
2 stops9h 50m
Southwest
Deal found 6/10![Southwest logo]()
$559
One-way flights from Islip to SeattleSearch for one-way flight options from Islip to Seattle. Find affordable one-way fares based on user searches. Data last updated June 12, 2026.
Search for one-way flight options from Islip to Seattle. Find affordable one-way fares based on user searches. Data last updated June 12, 2026.
This Southwest deal was found by Cheapflights users on 6/8. 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.
Sat 8/15:35 pm
ISP
- SEA
2 stops10h 40m
Southwest
Deal found 6/8![Southwest logo]()
$239
This Kiwi.com deal was found by Cheapflights users on 6/8. 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.
Sat 8/111:57 am
ISP
- SEA
3 stops48h 20m
Multiple Airlines
Deal found 6/8![Multiple Airlines logo]()
$260
This Kiwi.com deal was found by Cheapflights users on 6/8. 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.
Sun 6/289:52 pm
ISP
- SEA
2 stops19h 26m
Frontier
Deal found 6/8![Frontier logo]()
$283
This Kiwi.com deal was found by Cheapflights users on 6/8. 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 8/1211:57 am
ISP
- SEA
3 stops48h 07m
Multiple Airlines
Deal found 6/8![Multiple Airlines logo]()
$308
This Southwest deal was found by Cheapflights users on 6/8. 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 8/126:05 am
ISP
- SEA
1 stop9h 55m
Southwest
Deal found 6/8![Southwest logo]()
$321
This Kiwi.com deal was found by Cheapflights users on 6/8. 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 6/189:52 pm
ISP
- SEA
2 stops38h 56m
Frontier
Deal found 6/8![Frontier logo]()
$427
This Southwest deal was found by Cheapflights users on 6/8. 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.
Sun 6/286:00 am
ISP
- SEA
2 stops11h 15m
Southwest
Deal found 6/8![Southwest logo]()
$461
This Priceline deal was found by Cheapflights users on 6/8. 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 Priceline is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/182:11 pm
ISP
- SEA
1 stop11h 38m
Multiple Airlines
Deal found 6/8![Multiple Airlines logo]()
$767
This United deal was found by Cheapflights users on 6/8. 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 United is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 6/285:29 pm
ISP
- SEA
3 stops24h 07m
Multiple Airlines
Deal found 6/8![Multiple Airlines logo]()
$977
Find flight deals from Islip to Seattle
Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) to Seattle (SEA). 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 June 12, 2026.
Most accurate provider | FlightHub 3 stars |
|---|---|
Most trusted provider | FlightHub 3 stars |
Round-trip from | $405 (Southwest) |
One-way from | $239 (Southwest) |
Popular in | December |
Cheapest in | October |
Average price | $487 |
Cheapflights Fare Finder
Customize your flight search to find flights from Islip to Seattle 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 June 12, 2026.
Use the filters below to find and compare flights from Islip to Seattle that are best for you.
Fly from
Fly to
Route
Depart
Return
Cheapest round-trip
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Sat 8/22
5:30 am-10:45 am
1 stop8h 15m
Seattle/Tacoma Intl
Fri 8/28
10:30 pm-2:30 pm
1 stop13h 00m
$452
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Fri 9/4
10:20 am-5:35 pm
2 stops10h 15m
Seattle/Tacoma Intl
Fri 9/11
11:05 pm-2:30 pm
2 stops12h 25m
$467
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Tue 9/1
3:20 pm-11:25 pm
2 stops11h 05m
Seattle/Tacoma Intl
Thu 9/3
10:30 pm-9:40 am
1 stop8h 10m
$476
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Fri 10/2
12:35 pm-10:45 pm
2 stops13h 10m
Seattle/Tacoma Intl
Fri 10/9
12:15 am-3:35 pm
2 stops12h 20m
$477
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Sun 8/23
4:35 pm-12:50 am
2 stops11h 15m
Seattle/Tacoma Intl
Sun 8/30
11:00 pm-12:35 pm
2 stops10h 35m
$477
Quickest round-trip
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Tue 7/7
4:40 pm-12:35 am
2 stops10h 55m
Seattle/Tacoma Intl
Tue 7/14
9:25 pm-8:05 am
1 stop7h 40m
$508
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Wed 7/8
12:25 pm-8:10 pm
2 stops10h 45m
Seattle/Tacoma Intl
Wed 7/15
9:25 pm-8:20 am
1 stop7h 55m
$518
Cheapest one-way
Quickest one-way
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Sat 8/1
5:35 pm-1:15 am
2 stops10h 40m
$239
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Wed 8/12
3:20 pm-11:25 pm
2 stops11h 05m
$239
IslipSeattle
ISP - SEA
ISPSEA
Islip Long Island
Wed 8/12
11:57 am-9:04 am
3 stops48h 07m
$308
Showing 1-10 of 12 resultsSorted by cheapest first
Compare providers for flights from Islip to Seattle
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 Seattle in June.
| Provider | Price Accuracy | Trust Score* |
|---|---|---|
| Price Accuracy1 star | Trust Score*3 stars | |
| Price Accuracy3 stars | Trust Score*3 stars |
- Most accurate provider: When it comes to deals on Islip, New York-Seattle flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Islip, New York-Seattle flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Islip, New York-Seattle flight searches over the past month and is updated monthly.
- Most trusted provider: When it comes to deals on Islip, New York-Seattle flights, Cheapflights users trust FlightHub the most. FlightHub 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-Seattle 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 Seattle
Have a flexible travel schedule? Discover the best time to fly to Seattle from Islip with our price prediction graph.
ISP-SEA
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.
Related info for your journey
Find useful and relevant information for your journey from Islip to Seattle. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.
Traveling to a place near Seattle?
Book flights to Seattle if you plan to visit one of these locationsSeaTac
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