What is the cheapest airline to fly from Portland to Islip, New York round-trip?

Currently priced at $361, Southwest will fly you from Portland to Islip, New York and back. In addition to Southwest, many other airlines offer competitively priced options for your trip.

In terms of precipitation, rainfall in Islip, New York ranges from 3.3 - 4.4 inches per month. March is typically the wettest month, when rainfall can reach 4.4 in. February is typically the driest time to visit Islip, New York when rainfall is around 3.3 in.

If weather is an important factor for your trip to Islip, New York, use this chart to help with planning. For those seeking warmer temperatures, July is the ideal time of year to visit, when temperatures reach an average of 73.4 F. Travelers looking to avoid the cold should look outside of January, when temperatures are typically at their lowest (around 30.2 F).

What is the cheapest time of day to fly from PDX to ISP?

Regardless of the time of day you decide to fly, the ticket price will remain around the same. Book flights from Portland to Islip, New York as you normally would.

Most accurate provider : When it comes to deals on Portland-Islip, New York flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Portland-Islip, New York flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Portland-Islip, New York flight searches over the past month and is updated monthly.

Most trusted provider : When it comes to deals on Portland-Islip, New York flights, Cheapflights users trust eDreams the most. eDreams 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 Portland-Islip, New York flight deals. Provider user feedback score is based on Cheapflights searches over the past month and is updated monthly.

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

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

How can I find direct flights from Portland to Islip?

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

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

Yes. Cheapflights offers flight deals from Portland to Islip by cabin class. In addition to browsing deals, you can also filter by cabin class on the search results page after making a search.

$468+ Flights from Portland to Islip, NY

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1. Tell us where you want to go

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Cheap flight deals from Portland to Islip

Cheapest flights from Portland to Islip
Explore the most affordable flight options available from Portland to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 9, 2025.

Wed 12/249:42 pmPDX - ISP

1 stop10h 23mMultiple Airlines

Sun 12/2812:30 pmISP - PDX

1 stop11h 06mMultiple Airlines

Deal found 12/9

$2,065

Best flights from Portland to Islip
Discover carefully curated flight deals from Portland to Islip that have cost, travel time, and layovers in mind to ensure you get the best travel experience. Data last updated December 9, 2025.

Wed 12/249:42 pmPDX - ISP

1 stop10h 23mMultiple Airlines

Sun 12/2812:30 pmISP - PDX

1 stop11h 06mMultiple Airlines

Deal found 12/9

$2,065

Last-minute flights from Portland to Islip
Discover last-minute flight deals from Portland to Islip. Data last updated December 9, 2025 and is based on user searches.

Wed 12/249:42 pmPDX - ISP

1 stop10h 23mMultiple Airlines

Sun 12/2812:30 pmISP - PDX

1 stop11h 06mMultiple Airlines

Deal found 12/9

$2,065

One-way flights from Portland to Islip
Search for one-way flight options from Portland to Islip. Find affordable one-way fares based on user searches. Data last updated December 9, 2025.

Tue 2/36:00 amPDX - ISP

2 stops10h 45mMultiple Airlines

Deal found 12/7

$468

Sun 1/256:00 amPDX - ISP

2 stops10h 45mMultiple Airlines

Deal found 12/7

$594

Thu 12/188:32 pmPDX - ISP

2 stops11h 33mMultiple Airlines

Deal found 12/7

$621

Thu 1/226:00 amPDX - ISP

2 stops10h 45mMultiple Airlines

Deal found 12/7

$624

Wed 2/46:00 amPDX - ISP

2 stops10h 45mMultiple Airlines

Deal found 12/8

$654

Thu 12/256:14 amPDX - ISP

2 stops10h 31mMultiple Airlines

Deal found 12/7

$681

Tue 1/206:00 amPDX - ISP

2 stops10h 45mMultiple Airlines

Deal found 12/6

$740

Thu 1/16:14 amPDX - ISP

2 stops10h 31mMultiple Airlines

Deal found 12/7

$750

Sat 1/246:00 amPDX - ISP

2 stops10h 45mMultiple Airlines

Deal found 12/8

$770

Sun 1/48:32 pmPDX - ISP

2 stops11h 33mMultiple Airlines

Deal found 12/8

$787

Fri 1/166:00 amPDX - ISP

2 stops10h 45mMultiple Airlines

Deal found 12/7

$808

Sat 12/278:32 pmPDX - ISP

2 stops11h 33mMultiple Airlines

Deal found 12/8

$882

Find flight deals from Portland to Islip

Most accurate provider	eDreams 3 stars
Most trusted provider	eDreams 3 stars
Round-trip from	$2,065 (Expedia)
One-way from	$468 (Cheapflightsfares)
Popular in	December
Cheapest in	February
Average price	$526

Provider with most accurate pricing for Portland-Islip Long Island flight deals.

Search Deals

Provider most trusted by Cheapflights users for Portland-Islip Long Island flights.

Search Deals

From Portland to Islip Long Island

Search Deals

One-way flight from Portland to Islip Long Island

Search Deals

Highest demand for flights based on searches. 7% potential increase in price ($30 potential increase over avg. RT price).

Search Deals

Cheapest flight prices on average. 3% potential price decrease ($14 potential savings vs. average RT price).

Search Deals

Average for round-trip flights in December 2025

Search Deals

Fly from

Fly to

Route

Depart

Return

Price

PortlandIslip

PDX - ISP

PDXISP

Portland

Wed 12/24

9:42 pm-11:05 am

1 stop10h 23m

Islip Long Island

Sun 12/28

12:30 pm-8:36 pm

1 stop11h 06m

$2,065

PortlandIslip

PDX - ISP

PDXISP

Portland

Tue 2/3

6:00 am-7:45 pm

2 stops10h 45m

$468

PortlandIslip

PDX - ISP

PDXISP

Portland

Sun 1/25

6:00 am-7:45 pm

2 stops10h 45m

$594

PortlandIslip

PDX - ISP

PDXISP

Portland

Thu 1/22

6:00 am-7:45 pm

2 stops10h 45m

$624

PortlandIslip

PDX - ISP

PDXISP

Portland

Wed 2/4

6:00 am-7:45 pm

2 stops10h 45m

$654

PortlandIslip

PDX - ISP

PDXISP

Portland

Thu 1/15

6:00 am-7:45 pm

2 stops10h 45m

$681

PortlandIslip

PDX - ISP

PDXISP

Portland

Thu 12/25

6:14 am-7:45 pm

2 stops10h 31m

$681

PortlandIslip

PDX - ISP

PDXISP

Portland

Tue 1/20

6:00 am-7:45 pm

2 stops10h 45m

$740

PortlandIslip

PDX - ISP

PDXISP

Portland

Sun 1/4

8:32 pm-11:05 am

2 stops11h 33m

$750

PortlandIslip

PDX - ISP

PDXISP

Portland

Mon 3/16

6:00 am-7:45 pm

2 stops10h 45m

$750

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/7

Showing 1-10 of 11 results

Compare providers for flights from Portland to Islip

Use the table below to compare price accuracy, trust ratings, and cancellation policies for each provider offering flight deals from Portland to Islip in December.

Provider	Price Accuracy	Trust Score*
FlightHub	Price Accuracy3 stars	Trust Score*1 star
Expedia	Price Accuracy2 stars	Trust Score*3 stars
eDreams	Price Accuracy3 stars	Trust Score*3 stars

*The Trust Score is based on feedback from users after their booking experience. It measures overall satisfaction, helping us identify issues like hidden fees, problems during the ticketing process, and the quality of customer service. This score is our best indicator of the provider's quality and reliability.

Most accurate provider: When it comes to deals on Portland-Islip, New York flights, users find the pricing of eDreams to be most consistent on Cheapflights vs. eDreams Users can find the same prices on Portland-Islip, New York flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Portland-Islip, New York flight searches over the past month and is updated monthly.
Most trusted provider: When it comes to deals on Portland-Islip, New York flights, Cheapflights users trust eDreams the most. eDreams 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 Portland-Islip, New York 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 Portland to Islip

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

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

Currently, February is the cheapest month in which you can book a flight from Portland to Islip, New York (average of $106). Flying from Portland to Islip, New York in October is currently the most expensive (average of $257). 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.

Reviews of airlines servicing Islip

Read through reviews of airlines operating flights from Portland to Islip, such as Southwest. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Southwest

8.0

Very good

4,254 reviews

Reviews

1 / 20

2.0

Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am

Southwest

8.0

Very good

4,254 reviews

Southwest

8.0

Very good

4,254 reviews

Reviews

1 / 20

2.0

Mediocre

Thomas,Dec 2025

SEA - DEN

Plane two hours late in leaving 1:00 pm west coat time got home next day at 2:45am most car rental places are closed and don’t open till 5am

Related info for your journey

What is the cheapest airline to fly from Portland to Islip, New York round-trip?
Currently priced at $361, Southwest will fly you from Portland to Islip, New York and back. In addition to Southwest, many other airlines offer competitively priced options for your trip.
Can I find deals for flights from Portland to Islip that include hotel bookings?
Yes. In addition to deals on Portland to Islip flights, Cheapflights offers vacation packages that include both flights and hotel.
How can I find direct flights from Portland to Islip?
After entering your origin and destination, apply the non-stop filter on the search result page to find direct flights from Portland to Islip.
Can I find deals for business class flights from Portland to Islip?
Yes. Cheapflights offers flight deals from Portland to Islip 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 Portland to Islip, New York?
Currently, February is the cheapest month in which you can book a flight from Portland to Islip, New York (average of $106). Flying from Portland to Islip, New York in October is currently the most expensive (average of $257). 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

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Top airline flying from Portland to Islip

Airline	Cheapest	Average	Flexibility	On-time
Southwest	Cheapest$361	Average$437	FlexibilityNo cancel fee	On-time63%

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$468+ Cheap flights from Portland to Islip, NY (PDX - ISP)

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 2/3. Fares are subject to change and may not be available on all flights or dates of travel.

Find cheap flights from Portland to Islip with Cheapflights

1. Tell us where you want to go

2. Select your favorite providers

3. Compare prices and book

Cheap flight deals from Portland to Islip

Cheapest flights from Portland to IslipExplore the most affordable flight options available from Portland to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 9, 2025.

Explore the most affordable flight options available from Portland to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 9, 2025.

Find flight deals from Portland to Islip

Most accurate provider

Most trusted provider

Round-trip from

One-way from

Popular in

Cheapest in

Average price

Cheapflights Fare Finder

Use the filters below to find and compare flights from Portland to Islip that are best for you.

Compare providers for flights from Portland to Islip

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 Portland to Islip in December.

Best time to book a flight from Portland to Islip

Have a flexible travel schedule? Discover the best time to fly to Islip from Portland with our price prediction graph.

Cheapflights Insights

Everything you need to know about your flight from Portland to Islip

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

Reviews of airlines servicing Islip

Read through reviews of airlines operating flights from Portland to Islip, such as Southwest. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.

Related info for your journey

Find useful and relevant information for your journey from Portland to Islip. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

What is the cheapest airline to fly from Portland to Islip, New York round-trip?

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

How can I find direct flights from Portland to Islip?

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

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

Traveling to a place near Islip?

Browse thousands of different options on Cheapflights for your next trip

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Alternative routes for Portland to Islip

See prices for flight routes from nearby airports that may be better suited for you.

Top airline flying from Portland to Islip

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Cheapest flights from Portland to Islip
Explore the most affordable flight options available from Portland to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on December 9, 2025.