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$401+ Cheap flights from Islip to Portland (ISP - PDX)

This is the cheapest round-trip flight price found by a Cheapflights user in the last 72 hours by searching for a flight departing on 10/19. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — PDX
Oct 17 — Oct 241
Fri 10/17
Fri 10/24
1 adult, Economy
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Cheap flight deals from Islip to Portland

Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) to Portland (PDX). 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 17, 2025.

Round-trip from

$401
(Frontier)

Popular in

December

Cheapest in

January

Average price

$397
From Islip Long Island to Portland
Search Deals
Highest demand for flights based on searches. 4% potential increase in price ($19 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($15 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in September 2025
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Find flight deals from Islip to Portland

Cheapest flights from Islip to Portland
Explore the most affordable flight options available from Islip to Portland. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 17, 2025.

This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/199:47 pmISP - PDX
2 stops17h 01mFrontier
Sat 10/2512:43 pmPDX - ISP
2 stops17h 24mFrontier
Deal found 9/16$401
This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/199:47 pmISP - PDX
2 stops17h 01mFrontier
Tue 10/2812:52 pmPDX - ISP
2 stops18h 45mFrontier
Deal found 9/16$402
This Southwest deal was found by Cheapflights users on 9/16. 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 10/165:35 pmISP - PDX
2 stops9h 20mSouthwest
Thu 10/237:35 pmPDX - ISP
2 stops13h 15mSouthwest
Deal found 9/16$429
This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/199:47 pmISP - PDX
2 stops17h 01mFrontier
Fri 10/2412:43 pmPDX - ISP
2 stops20h 10mFrontier
Deal found 9/16$442
This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/169:37 pmISP - PDX
2 stops17h 11mFrontier
Wed 10/2212:43 pmPDX - ISP
2 stops17h 21mFrontier
Deal found 9/16$454
This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/169:37 pmISP - PDX
2 stops17h 11mFrontier
Tue 10/2812:52 pmPDX - ISP
2 stops18h 45mFrontier
Deal found 9/16$455
This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/169:37 pmISP - PDX
2 stops17h 11mFrontier
Fri 10/2412:43 pmPDX - ISP
2 stops20h 10mFrontier
Deal found 9/16$496
This Frontier deal was found by Cheapflights users on 9/16. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/199:47 pmISP - PDX
2 stops17h 01mFrontier
Sun 10/2612:43 pmPDX - ISP
2 stops18h 54mFrontier
Deal found 9/16$525
This Southwest deal was found by Cheapflights users on 9/15. 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 10/16:05 amISP - PDX
1 stop10h 45mSouthwest
Sun 10/57:05 pmPDX - ISP
2 stops13h 45mSouthwest
Deal found 9/15$618
This Trip.com deal was found by Cheapflights users on 9/15. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/111:35 amISP - PDX
1 stop12h 15mMultiple Airlines
Sun 10/510:16 amPDX - ISP
1 stop21h 24mMultiple Airlines
Deal found 9/15$755
This Trip.com deal was found by Cheapflights users on 9/15. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 10/211:40 amISP - PDX
1 stop12h 10mMultiple Airlines
Sun 10/510:16 amPDX - ISP
1 stop21h 24mMultiple Airlines
Deal found 9/15$781

Cheapflights Fare Finder

 
Customize your flight search to find flights from Islip to Portland 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 17, 2025.
Use the filters below to find and compare flights from Islip to Portland that are best for you.

Fly from

Islip

Fly to

Portland

Route

Depart

Return

Price

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Sun 10/19

9:47 pm-11:48 am

2 stops17h 01m

Portland

Sat 10/25

12:43 pm-9:07 am

2 stops17h 24m

$401

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Sun 10/19

9:47 pm-11:48 am

2 stops17h 01m

Portland

Thu 10/23

12:43 pm-9:04 am

2 stops17h 21m

$401

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Sun 10/19

9:47 pm-11:48 am

2 stops17h 01m

Portland

Wed 10/22

12:43 pm-9:04 am

2 stops17h 21m

$401

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Sun 10/19

9:47 pm-11:48 am

2 stops17h 01m

Portland

Tue 10/28

12:52 pm-10:37 am

2 stops18h 45m

$402

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Thu 10/16

5:35 pm-11:55 pm

2 stops9h 20m

Portland

Thu 10/23

7:35 pm-11:50 am

2 stops13h 15m

$429

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Sun 10/19

9:47 pm-11:48 am

2 stops17h 01m

Portland

Fri 10/24

12:43 pm-11:53 am

2 stops20h 10m

$442

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Thu 10/16

9:37 pm-11:48 am

2 stops17h 11m

Portland

Thu 10/23

12:43 pm-9:04 am

2 stops17h 21m

$454

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Thu 10/16

9:37 pm-11:48 am

2 stops17h 11m

Portland

Sat 10/25

12:43 pm-9:07 am

2 stops17h 24m

$454

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Thu 10/16

9:37 pm-11:48 am

2 stops17h 11m

Portland

Tue 10/28

12:52 pm-10:37 am

2 stops18h 45m

$455

IslipPortland

ISP - PDX

ISPPDX

Islip Long Island

Wed 10/1

6:05 am-1:50 pm

1 stop10h 45m

Portland

Sun 10/5

7:05 pm-11:50 am

2 stops13h 45m

$618

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/15

Showing 1-10 of 19 results
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Best time to book a flight from Islip to Portland

Have a flexible travel schedule? Discover the best time to fly to Portland from Islip 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 Islip to Portland

What is the cheapest month to book a flight from Islip to Portland?

Currently, November is the cheapest month in which you can book a flight from Islip to Portland (average of $277). Flying from Islip to Portland in March is currently the most expensive (average of $368). 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 Islip to Portland. 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 Islip to Portland?

    Departing from Islip to Portland will take you 9h 20m. Airlines will cover a distance of 2474 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • Can I find deals for flights from Islip to Portland that include hotel bookings?

    Yes. In addition to deals on Islip to Portland flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Islip to Portland?

    After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Islip to Portland.

  • Can I find deals for business class flights from Islip to Portland?

    Yes. Cheapflights offers flight deals from Islip to Portland 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 Islip to Portland?

    Currently, November is the cheapest month in which you can book a flight from Islip to Portland (average of $277). Flying from Islip to Portland in March is currently the most expensive (average of $368). 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 Portland?

Book flights to Portland if you plan to visit one of these locations
Vancouver
Seaside
Beaverton
Clackamas
McMinnville
Lake Oswego
Hillsboro
Cannon Beach
Long Beach
Longview
Lincoln City
Tigard
Depoe Bay
Stevenson
Wilsonville
Pacific City
Tillamook
Troutdale
Gresham
Silverton

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