What airlines fly to Seattle?

Alaska Airlines, United Airlines and Delta are the top three most popular airlines that fly to Seattle from Islip, New York according to our data. Alaska Airlines is the first choice among our users, with 44% of people opting to fly with this airline when traveling to Seattle. Keep in mind that there are 10 different airlines that fly to Seattle on a routine basis, so you have a few additional options to choose from.

When did momondo last update prices for flights from Islip Long Island Airport to Seattle/Tacoma Intl Airport?

Prices for flights from Islip Long Island Airport to Seattle/Tacoma Intl Airport are refreshed on a daily basis.

How many operators does momondo search for flights from Islip Long Island Airport to Seattle/Tacoma Intl Airport?

As of November 2025, there is 1 operator available to choose from for flights from Islip Long Island Airport to Seattle/Tacoma Intl Airport.

How old do you have to be to fly from Islip Long Island Airport to Seattle/Tacoma Intl Airport?

The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Islip Long Island Airport to Seattle/Tacoma Intl Airport.

What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?

The required travel and health documents for your Seattle/Tacoma Intl Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.

$206 Cheap Flights from Islip to Seattle in 2025/26

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Find the cheapest flights from Islip, New York to Seattle

Round-trip

One-way

Cheap round-trip flights

Enter your travel dates to find the best prices.

2:00 pm - 1:25 amISP-SEA

14h 25m2 stops

11:55 pm - 11:45 amSEA-ISP

8h 50m2 stops

$457Southwest

Find Deal

Fri, Mar 6 - Mon, Mar 9

12:25 pm - 11:55 pmISP-SEA

14h 30m2 stops

11:55 pm - 1:50 pmSEA-ISP

10h 55m2 stops

$463Southwest

Find Deal

Wed, Apr 1 - Mon, Apr 13

10:19 am - 7:18 pmISP-SEA

35h 59m2 stops

11:10 pm - 11:05 amSEA-ISP

8h 55m1 stop

$871Multiple Airlines

Find Deal

Sat, Dec 13 - Wed, Dec 17

9:59 am - 10:00 pmISP-SEA

15h 01m1 stop

10:40 pm - 11:05 amSEA-ISP

9h 25m1 stop

$893Multiple Airlines

Find Deal

Fri, Mar 6 - Mon, Mar 9

3:55 pm - 10:55 pmISP-SEA

10h 00m2 stops

8:35 am - 11:50 pmSEA-ISP

12h 15m2 stops

$907Southwest

Find Deal

Tue, Dec 9 - Fri, Dec 12

7:25 am - 1:26 pmISP-SEA

9h 01m1 stop

8:20 am - 7:45 pmSEA-ISP

8h 25m1 stop

$964Multiple Airlines

Find Deal

Sun, Mar 29 - Wed, Apr 1

8:29 pm - 7:18 pmISP-SEA

25h 49m2 stops

9:00 am - 7:45 pmSEA-ISP

7h 45m1 stop

$1,149Multiple Airlines

Find Deal

Tue, Dec 9 - Fri, Dec 12

5:40 am - 3:15 pmISP-SEA

12h 35m2 stops

8:35 pm - 12:50 pmSEA-ISP

13h 15m2 stops

$1,239Southwest

Find Deal

Sun, Dec 28 - Sun, Jan 4

12:30 pm - 10:30 pmISP-SEA

13h 00m1 stop

11:10 pm - 11:05 amSEA-ISP

8h 55m1 stop

$1,274Multiple Airlines

Find Deal

Tue, Dec 9 - Fri, Dec 12

12:30 pm - 10:52 amISP-SEA

25h 22m1 stop

8:05 am - 1:09 pmSEA-ISP

26h 04m2 stops

$1,680Multiple Airlines

Find Deal

Sun, Dec 28 - Sun, Jan 4

Southwest flights from Islip, New York to Seattle

Our best Southwest deals on Islip, New York to Seattle flight tickets

Southwest

Mar 6

ISP2:00 pmIslip Long Island

14h 25m

2 stops

SEA1:25 amSeattle/Tacoma Intl

Mar 9

SEA11:55 pmSeattle/Tacoma Intl

8h 50m

2 stops

ISP11:45 amIslip Long Island

$457

Find similar

Southwest

Apr 1

ISP12:25 pmIslip Long Island

14h 30m

2 stops

SEA11:55 pmSeattle/Tacoma Intl

Apr 13

SEA11:55 pmSeattle/Tacoma Intl

10h 55m

2 stops

ISP1:50 pmIslip Long Island

$463

Find similar

Southwest

Dec 9

ISP3:55 pmIslip Long Island

10h 00m

2 stops

SEA10:55 pmSeattle/Tacoma Intl

Dec 12

SEA8:35 amSeattle/Tacoma Intl

12h 15m

2 stops

ISP11:50 pmIslip Long Island

$907

Find similar

Fly from

Fly to

Route

Depart

Return

Price

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Fri 3/6

2:00 pm-1:25 am

2 stops14h 25m

Seattle/Tacoma Intl

Mon 3/9

11:55 pm-11:45 am

2 stops8h 50m

$457

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Wed 4/1

12:25 pm-11:55 pm

2 stops14h 30m

Seattle/Tacoma Intl

Mon 4/13

11:55 pm-1:50 pm

2 stops10h 55m

$463

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Sat 12/13

10:19 am-7:18 pm

2 stops35h 59m

Seattle/Tacoma Intl

Wed 12/17

11:10 pm-11:05 am

1 stop8h 55m

$871

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Fri 3/6

9:59 am-10:00 pm

1 stop15h 01m

Seattle/Tacoma Intl

Mon 3/9

10:40 pm-11:05 am

1 stop9h 25m

$893

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Tue 12/9

3:55 pm-10:55 pm

2 stops10h 00m

Seattle/Tacoma Intl

Fri 12/12

8:35 am-11:50 pm

2 stops12h 15m

$907

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Sun 3/29

7:25 am-1:26 pm

1 stop9h 01m

Seattle/Tacoma Intl

Wed 4/1

8:20 am-7:45 pm

1 stop8h 25m

$964

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Tue 12/9

8:29 pm-7:18 pm

2 stops25h 49m

Seattle/Tacoma Intl

Fri 12/12

9:00 am-7:45 pm

1 stop7h 45m

$1,149

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Sun 12/28

5:40 am-3:15 pm

2 stops12h 35m

Seattle/Tacoma Intl

Sun 1/4

8:35 pm-12:50 pm

2 stops13h 15m

$1,239

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Tue 12/9

12:30 pm-10:30 pm

1 stop13h 00m

Seattle/Tacoma Intl

Fri 12/12

11:10 pm-11:05 am

1 stop8h 55m

$1,274

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Sun 12/28

12:30 pm-10:52 am

1 stop25h 22m

Seattle/Tacoma Intl

Sun 1/4

8:05 am-1:09 pm

2 stops26h 04m

$1,680

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 16 resultsSorted by cheapest first

How to get the cheapest flight ticket from Islip, New York to Seattle

Look no further. We've gone through all the searches for this route on momondo so you have the important information and insights to find the cheapest flight ticket for your trip

Prices

Airlines

What is the cheapest day to depart on your flight to Seattle?

On average, the least expensive day to fly to Seattle from Islip, New York is on a Wednesday. momondo users have found tickets for Wednesday departures for as low as $465. However, this price may fluctuate depending on the airline, the season, and holidays. On the other hand, Sunday is the most expensive day to depart from Islip, New York because it is more convenient for both business and leisure travelers. As a result, prices tend to be around $556.

What is the cheapest time of day to depart on your flight to Seattle?

Flying to Seattle from Islip, New York in the evening is the least expensive time of day to depart. momondo users have found prices as low as $379 when looking at flights departing in the evening. Flights to Seattle are more costly at noon, with an average ticket price of $573. Departure times at noon fall within the peak daily travel times, which is why tickets can be more expensive.

Can stopping save me money on Islip, New York to Seattle flights?

You could potentially save up to 6% on your flight if you consider stops on a Islip, New York to Seattle flight.

When to book flights from Islip, New York to Seattle

Are you open to changing your travel dates? Check out the ideal times to fly from Islip, New York to Seattle according to our flight data. Find out which month and days have the cheapest flights.

Estimated round-trip price

Cheap Islip, New York to Seattle (ISP to SEA) flight deals and tips

Find info about flight duration, direct flights, and airports for your flight from Islip, New York to Seattle

Fastest flight time	9h 01m
Direct flights	None

The fastest flight from Islip, New York to Seattle takes 9h 01m

There are no direct flights from Islip, New York to Seattle. There are no popular flight routes from Islip, New York to Seattle.

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How far is Islip Long Island to Seattle/Tacoma Intl by plane?
Seattle/Tacoma Intl is 2436.8 mi away from Islip Long Island. By plane, this route typically takes 9h 01m.
When did momondo last update prices for flights from Islip Long Island Airport to Seattle/Tacoma Intl Airport?
Prices for flights from Islip Long Island Airport to Seattle/Tacoma Intl Airport are refreshed on a daily basis.
How many operators does momondo search for flights from Islip Long Island Airport to Seattle/Tacoma Intl Airport?
As of November 2025, there is 1 operator available to choose from for flights from Islip Long Island Airport to Seattle/Tacoma Intl Airport.
How old do you have to be to fly from Islip Long Island Airport to Seattle/Tacoma Intl Airport?
The minimum age for a child to fly alone is five, but airlines that offer an unaccompanied minor (UNMR) service may have their own age limitations. Flight duration, scheduling, and layovers are among the considerations that may influence age limits. We recommend that you double-check with the airline you are booking with for travel from Islip Long Island Airport to Seattle/Tacoma Intl Airport.
What documentation or ID do you need to fly to Seattle/Tacoma Intl Airport?
The required travel and health documents for your Seattle/Tacoma Intl Airport trip may vary depending on your itinerary and personal circumstances. As a general rule, you should carry multiple documents, including a national ID card or driver's license and a passport valid for six months after your intended arrival at Seattle/Tacoma Intl Airport. We recommend that you seek guidance from your airline or a reliable third party such as IATA.
What is the most popular airline from Islip, New York to Seattle?
momondo data reveals that the most frequently booked airline on the route from Islip, New York to Seattle is Southwest, representing 100% of all bookings.

Best airlines flying from Islip, New York to Seattle

Compare and see reviews for airlines that fly from Islip, New York to Seattle with momondo

Airline	Rating	Free Cancellation	Price
Southwest	PriceFrom $356	Free Cancellation	Rating 8.0 4,251 reviews		Search Southwest flights

Tacoma

Leavenworth

SeaTac

Ocean Shores

Renton

Olympia

Lynnwood

Kent

Marysville

Puyallup

Redmond

Tukwila

Cle Elum

Lakewood

Federal Way

Fife

Centralia

Kirkland

Westport

Shoreline

Why use momondo?

Why should I use momondo to find a flight deal from Islip to Seattle?

Finding the right flight to Seattle from Islip is quick and easy when you have a range of options in front of you, from reputable agents and recognisable airlines. Options that can then be filtered down to find the best fit. That is what momondo does. We make finding flights to Seattle quick and easy, saving you time and money.

Can I find flights from Islip to Seattle with flexible booking policies on momondo?

Yes. momondo enables you to select and highlight flights to Seattle from Islip with this policy.

How can momondo help me find flights from Islip to Seattle?

Once you have performed a search in the form on the page, momondo provides useful filters and insights. We can show you the cheapest days and times to fly as well as help filter your options to help you make an informed choice when booking flights to Seattle from Islip.

I’m not ready to book a flight from Islip to Seattle right now. Can momondo alert me if prices change?

If you are simply researching potential flights to Seattle, momondo offers a useful price alert feature which will track prices for flights to Seattle from Islip and alert you when they change.