ISP - SEA

$485 Find Cheap Flights from Islip to Seattle

This is the cheapest round-trip flight price found by a KAYAK user in the last 72 hours by searching for a flight from Islip to Seattle departing on 2/16. Fares are subject to change and may not be available on all flights or dates of travel. Click the price to replicate the search for this deal.
1 adult
1 adult, Economy, 0 bags

KAYAK searches hundreds of travel sites at once for deals on flights to Seattle

 
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Islip to Seattle, as well as popular online travel agencies
These are the airlines KAYAK users have selected most often from within our search results in flight searches from Islip to Seattle, as well as popular online travel agencies
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Everything you should know

Cheapest round-trip
$485
Southwest
Mon 2/16Sun 2/22
ISP - SEA • 2 stops
Cheapest one-way
Multiple Airlines
Thu 12/18
ISP - SEA • multi-stop
Top airlines
Southwest
Cheapest • from $485 (round-trip)
Southwest
Best reviews • 7.9 score
Airline reviews
Airline reviews
+1
+1
Airline reviews
Airline reviews
+1
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Flight Deals
Booking Insights
Flight Deals

Cheap Flights from Islip to Seattle (ISP-SEA)

 
Here are some of the best deals found on KAYAK recently from the most popular airlines for round-trip flights from Islip to Seattle that are departing in the next months. While these flights were available on KAYAK in the last 72 hours, prices and availability are subject to change and deals may expire.
Discover the best prices for you by selecting your travel dates on KAYAK.

Recent round-trip flight deals from Islip to Seattle

Mon, Feb 16 - Sun, Feb 22
Southwest Logo
1:10 pm - 12:10 am
ISP
-
SEA
14h 00m2 stops
Southwest Logo
6:25 pm - 11:55 am
SEA
-
ISP
14h 30m2 stops
$485Southwest
Tue, Dec 30 - Sat, Jan 3
Frontier Logo
12:20 pm - 12:30 pm
ISP
-
SEA
27h 10m2 stops
Frontier Logo
6:12 pm - 7:39 pm
SEA
-
ISP
22h 27m2 stops
$896Frontier
Mon, Feb 16 - Sun, Feb 22
Multiple Airlines Logo
12:30 pm - 10:00 pm
ISP
-
SEA
12h 30m1 stop
Multiple Airlines Logo
7:55 am - 12:53 am
SEA
-
ISP
37h 58m2 stops
$975Multiple Airlines
Mon, Feb 16 - Sun, Feb 22
Multiple Airlines Logo
12:30 pm - 10:00 pm
ISP
-
SEA
12h 30m1 stop
Multiple Airlines Logo
10:40 pm - 11:05 am
SEA
-
ISP
9h 25m1 stop
$979Multiple Airlines
Tue, Dec 30 - Sat, Jan 3
Southwest Logo
1:35 pm - 12:55 am
ISP
-
SEA
14h 20m2 stops
Southwest Logo
6:15 am - 8:50 pm
SEA
-
ISP
11h 35m2 stops
$997Southwest
Thu, Jan 1 - Mon, Jan 5
Multiple Airlines Logo
12:30 pm - 9:30 pm
ISP
-
SEA
12h 00m1 stop
Multiple Airlines Logo
1:43 pm - 11:05 am
SEA
-
ISP
18h 22m2 stops
$1,439Multiple Airlines
Thu, Jan 1 - Mon, Jan 5
Multiple Airlines Logo
12:30 pm - 9:30 pm
ISP
-
SEA
12h 00m1 stop
Multiple Airlines Logo
11:25 pm - 4:10 pm
SEA
-
ISP
13h 45m1 stop
$1,485Multiple Airlines
Tue, Dec 30 - Sat, Jan 3
Multiple Airlines Logo
12:30 pm - 9:30 pm
ISP
-
SEA
12h 00m1 stop
Multiple Airlines Logo
11:25 pm - 4:10 pm
SEA
-
ISP
13h 45m1 stop
$2,054Multiple Airlines
Booking Insights

KAYAK's insights & trends for Islip to Seattle flights

Get data-powered insights and trends into flights from Islip to Seattle to help you find the cheapest flights, the best time to fly and much more.

Which airlines provide the cheapest flights from Islip to Seattle?

The cheapest round-trip price for the route for each airline clicked by KAYAK users in the last 72 hours.

In the past 3 days, the cheapest round-trip tickets from Islip to Seattle were found on Southwest ($485) and Frontier ($896).

Which airlines fly non-stop between Islip and Seattle?

Airline and price data is aggregated from results in KAYAK’s search results from the last 2 weeks for round-trip flights from Islip to Seattle.

There is just one airline that flies from Islip to Seattle direct and that is Southwest. The best round-trip deal found from Southwest for the route is $356.

Find deals

Good to know

Cheapest flight$485
Flight from Islip to Seattle

When to book flights from Islip to Seattle

Are your dates flexible? Find out the best times to travel from Islip to Seattle based on our flight data from the last year. Discover the cheapest month and even day to fly.
Estimated round-trip price
KAYAK looks at all historical flight data for each date to provide a predicted price for one-way trips or round-trips with a duration up to 40 days. While we try to provide actual minimum prices for each date, some prices are predictions and actual prices may differ.

FAQs for booking flights from Islip to Seattle

  • What is the cheapest flight from Islip to Seattle?

    In the last 3 days, the lowest price for a flight from Islip to Seattle was $485 for a round-trip ticket.

  • Do I need a passport to fly between Islip and Seattle?

    A passport is not required to fly from Islip to Seattle.

  • Which airports will I be using when flying from Islip to Seattle?

    Islip airport is called Islip Long Island and the only airport in Seattle is Seattle/Tacoma Intl.

  • Which aircraft models fly most regularly from Islip to Seattle?

    We unfortunately don’t have that data for this specific route.

  • How does KAYAK find such low prices on flights from Islip to Seattle?

    KAYAK is a travel search engine. That means we look across the web to find the best prices we can find for our users. With over 2 billion flight queries processed yearly, we are able to display a variety of prices and options on flights from Islip to Seattle.

  • How does KAYAK's flight Price Forecast tool help me choose the right time to buy my flight ticket from Islip to Seattle?

    KAYAK’s flight Price Forecast tool uses historical data to determine whether the price for a flight to Seattle from Islip is likely to change within 7 days, so travelers know whether to wait or book now.

  • What is the Hacker Fare option on flights from Islip to Seattle?

    Hacker Fares allow you to combine one-way tickets in order to save you money over a traditional round-trip ticket. You could then fly to Seattle with an airline and back to Islip with another airline. Booking your flights between Islip and SEA can sometimes prove cheaper using this method.

  • What is KAYAK's "flexible dates" feature and why should I care when looking for a flight from Islip to Seattle?

    Sometimes travel dates aren't set in stone. If your preferred travel dates have some wiggle room, flexible dates will show you all the options when flying to Seattle from Islip up to 3 days before/after your preferred dates. You can then pick the flights that suit you best.

Reviews of the top airline flying from Islip to Seattle

 
See real verified KAYAK customer reviews for airlines flying from Islip to Seattle. Airline scores are aggregated from all reviews left by passengers on KAYAK after flying with an airline. KAYAK doesn’t show reviews that are older than 5 years. Learn how KAYAK collects reviews.
Need help choosing which airline to fly with from Islip to Seattle? KAYAK airline reviews give an overall score for each airline based on loads of factors, including comfort, boarding, in-flight entertainment and more, to make your decision easier. See airline scores according to verified KAYAK customer reviews.
7.9
SouthwestOverall score based on 4250 reviews
8.1Boarding
7.5Entertainment
7.0Food
8.0Comfort
8.6Crew
Airline reviews

They sent a notice that they were boarding an hour early. We had to leave the club and run to the gate. They said sorry, that came from corporate and was a mistake. They did not have enough seating because the flight before it had not taken off on time. They moved our gate and delayed it for an hour.

2.0 MediocreRobert, Dec 2025
LAS - TPA
Read more Southwest reviews

They sent a notice that they were boarding an hour early. We had to leave the club and run to the gate. They said sorry, that came from corporate and was a mistake. They did not have enough seating because the flight before it had not taken off on time. They moved our gate and delayed it for an hour.

The boarding and seat assignment system no longer works for me, but I know it is being replaced. Otherwise, I am good with the overall experience.

The lead steward kept singing about "San Francisco" and hotel California---more annoying than humorous....needs work. Flight was smooth and on time.

Still a fan of open seating. Flight was on schedule and arrived on time. The 737 MAX is very comfortable.

Airline travel is always too cramped to really be pleasant, but the cabin crew on this flight did a pretty good job of making up for it by putting on some music during boarding and sprinkling a few funny remarks into the safety briefing and announcements, and just generally being friendly and helpful. It definitely reminded me of why I prefer the in-flight experience on Southwest!

No delays and arrived to destination 30 min early. Staff was super friendly.

San Diego airport is brand new, spacious, airy and very smooth checkin at SW baggage drop.

It was rough. The staff was unprofessional, the choice of on board drinks terrible, it was cramped in space at every airport, they always ran out of overhead bin space so they pressured people to check bags for free or we couldn’t leave on the plane— so I did check my bag to help, and they nearly lost my bag. My bag did not arrive on the luggage belt, another man on my flight and I had to waste our time going to the baggage office to search for our bags. I would only fly southwest again if it was my last choice. Also, my flights were consistently delayed over and over again— at one point they straight up told us we were waiting for the pilot to arrive.

Crew could have been friendlier, maybe I'm spoiled by SW crews. In flight wifi was good. Would be nice to have more food offerings on a 4 plus hour flight

Had to get off plane from prior flight even though I had to reboard same plane to continue to my final destination.

Everything you need to know for your flight from Islip to Seattle

Information on your arrival and departure airports

Islip (ISP)
Seattle (SEA)