What is the cheapest airline that flies from Islip Long Island to Seattle/Tacoma Intl?

Frontier and Southwest are the most popular carriers operating from Islip Long Island to Seattle/Tacoma Intl

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 51% 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 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.

$203 Cheap Flights from Islip, New York to Seattle in 2026

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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.

4:30 pm - 12:55 am

ISP

SEA

11h 25m

2 stops

9:25 pm - 8:20 am

SEA

ISP

7h 55m

1 stop

$474Southwest

Mon, Jun 1 - Sun, Jun 7

4:05 pm - 10:55 pm

ISP

SEA

9h 50m

2 stops

6:50 pm - 9:40 am

SEA

ISP

11h 50m

2 stops

$477Southwest

Thu, Aug 20 - Sun, Aug 23

4:30 pm - 12:55 am

ISP

SEA

11h 25m

2 stops

11:05 pm - 11:50 am

SEA

ISP

9h 45m

2 stops

$503Southwest

Mon, Jun 1 - Sun, Jun 7

6:10 am - 1:55 pm

ISP

SEA

10h 45m

2 stops

10:30 pm - 9:40 am

SEA

ISP

8h 10m

1 stop

$532Southwest

Thu, Aug 20 - Sun, Aug 23

12:30 pm - 11:55 pm

ISP

SEA

14h 25m

2 stops

9:25 pm - 11:10 pm

SEA

ISP

22h 45m

1 stop

$540Southwest

Tue, Jun 2 - Fri, Jun 5

12:30 pm - 9:50 pm

ISP

SEA

12h 20m

2 stops

9:25 pm - 8:20 am

SEA

ISP

7h 55m

1 stop

$559Southwest

Fri, Jul 10 - Sun, Jul 12

12:30 pm - 6:30 pm

ISP

SEA

9h 00m

1 stop

9:25 pm - 8:20 am

SEA

ISP

7h 55m

1 stop

$563Southwest

Fri, Jul 10 - Sun, Jul 12

6:30 am - 6:00 pm

ISP

SEA

14h 30m

2 stops

5:30 am - 11:35 pm

SEA

ISP

15h 05m

3 stops

$566Southwest

Tue, Jun 2 - Fri, Jun 5

12:30 pm - 9:50 pm

ISP

SEA

12h 20m

2 stops

10:45 pm - 11:50 am

SEA

ISP

10h 05m

2 stops

$579Southwest

Fri, Jul 10 - Sun, Jul 12

4:30 pm - 12:05 am

ISP

SEA

10h 35m

2 stops

5:45 am - 10:50 pm

SEA

ISP

14h 05m

2 stops

$588Southwest

Thu, May 14 - Sun, May 24

Southwest flights from Islip, New York to Seattle

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

Southwest

Jun 1

ISP4:30 pmIslip Long Island

11h 25m

2 stops

SEA12:55 amSeattle/Tacoma Intl

Jun 7

SEA9:25 pmSeattle/Tacoma Intl

7h 55m

1 stop

ISP8:20 amIslip Long Island

$474

Southwest

Aug 20

ISP4:05 pmIslip Long Island

9h 50m

2 stops

SEA10:55 pmSeattle/Tacoma Intl

Aug 23

SEA6:50 pmSeattle/Tacoma Intl

11h 50m

2 stops

ISP9:40 amIslip Long Island

$477

Southwest

Jun 1

ISP4:30 pmIslip Long Island

11h 25m

2 stops

SEA12:55 amSeattle/Tacoma Intl

Jun 7

SEA11:05 pmSeattle/Tacoma Intl

9h 45m

2 stops

ISP11:50 amIslip Long Island

$503

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Mon 6/1

4:30 pm-12:55 am

2 stops11h 25m

Seattle/Tacoma Intl

Sun 6/7

9:25 pm-8:20 am

1 stop7h 55m

$474

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Thu 8/20

4:05 pm-10:55 pm

2 stops9h 50m

Seattle/Tacoma Intl

Sun 8/23

6:50 pm-9:40 am

2 stops11h 50m

$477

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Mon 6/1

4:30 pm-12:55 am

2 stops11h 25m

Seattle/Tacoma Intl

Sun 6/7

11:05 pm-11:50 am

2 stops9h 45m

$503

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Thu 8/20

6:10 am-1:55 pm

2 stops10h 45m

Seattle/Tacoma Intl

Sun 8/23

10:30 pm-9:40 am

1 stop8h 10m

$532

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Tue 6/2

12:30 pm-11:55 pm

2 stops14h 25m

Seattle/Tacoma Intl

Fri 6/5

9:25 pm-11:10 pm

1 stop22h 45m

$540

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Fri 7/10

12:30 pm-9:50 pm

2 stops12h 20m

Seattle/Tacoma Intl

Sun 7/12

9:25 pm-8:20 am

1 stop7h 55m

$559

Quickest round-trip

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Fri 7/10

12:30 pm-6:30 pm

1 stop9h 00m

Seattle/Tacoma Intl

Sun 7/12

9:25 pm-8:20 am

1 stop7h 55m

$563

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Tue 6/2

6:30 am-6:00 pm

2 stops14h 30m

Seattle/Tacoma Intl

Fri 6/5

5:30 am-11:35 pm

3 stops15h 05m

$566

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Fri 7/10

12:30 pm-9:50 pm

2 stops12h 20m

Seattle/Tacoma Intl

Sun 7/12

10:45 pm-11:50 am

2 stops10h 05m

$579

IslipSeattle

ISP - SEA

ISPSEA

Islip Long Island

Thu 5/14

4:30 pm-12:05 am

2 stops10h 35m

Seattle/Tacoma Intl

Sun 5/24

5:45 am-10:50 pm

2 stops14h 05m

$588

Flights are sorted by cheapest round-trip flights first.

Showing 1-10 of 20 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 $442. 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 $513.

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 $373 when looking at flights departing in the evening. Flights to Seattle are more costly at noon, with an average ticket price of $567. 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 29% 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	10h 35m
Direct flights	None

The fastest flight from Islip, New York to Seattle takes 10h 35m

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

Search flight deals

Frequently asked questions about flying from Islip, New York to Seattle

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 10h 35m.
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 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.

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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.