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Islip

$54+ Cheap flights from Dulles Intl (IAD) to Islip, NY (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 1/5. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — ISP
Nov 27 — Dec 41
Thu 11/27
Thu 12/4
1 adult, Economy
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Cheap flight deals from Dulles Intl to Islip

Discover tips and strategies to find the most affordable flight options for your journey from Dulles Intl (IAD) to Islip (ISP). 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 October 28, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$140
(Kiwi.com)

One-way from

$64
(Trip.com)

Popular in

December

Cheapest in

April

Average price

$273
Provider with most accurate pricing for Washington, D.C. Dulles Intl-Islip Long Island flight deals.
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Provider most trusted by Cheapflights users for Washington, D.C. Dulles Intl-Islip Long Island flights.
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From Washington, D.C. Dulles Intl to Islip Long Island
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One-way flight from Washington, D.C. Dulles Intl to Islip Long Island
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Highest demand for flights based on searches. 19% potential increase in price ($49 potential increase over avg. RT price).
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Cheapest flight prices on average. 2% potential price decrease ($7 potential savings vs. average RT price).
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Average for round-trip flights in October 2025
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Find flight deals from Dulles Intl to Islip

Cheapest flights from Dulles Intl to Islip
Explore the most affordable flight options available from Dulles Intl to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on October 28, 2025.

This Kiwi.com deal was found by Cheapflights users on 10/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/2011:12 amIAD - ISP
1 stop23h 25mFrontier
Sun 11/238:25 pmISP - IAD
1 stop11h 20mFrontier
Deal found 10/26$140
This Kiwi.com deal was found by Cheapflights users on 10/25. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/2711:12 amIAD - ISP
1 stop23h 25mFrontier
Tue 12/28:29 pmISP - IAD
2 stops18h 00mFrontier
Deal found 10/25$181
This Trip.com deal was found by Cheapflights users on 10/28. 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.
Fri 11/148:36 pmIAD - ISP
1 stop14h 01mFrontier
Mon 11/179:54 amISP - IAD
2 stops14h 17mFrontier
Deal found 10/28$228
This Trip.com deal was found by Cheapflights users on 10/28. 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.
Mon 11/108:36 pmIAD - ISP
1 stop21h 06mFrontier
Wed 11/124:58 pmISP - IAD
1 stop26h 53mFrontier
Deal found 10/28$233
This Kiwi.com deal was found by Cheapflights users on 10/26. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 11/205:40 pmIAD - ISP
2 stops16h 57mMultiple Airlines
Sun 11/238:25 pmISP - IAD
1 stop11h 20mMultiple Airlines
Deal found 10/26$278
This Kiwi.com deal was found by Cheapflights users on 10/28. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 11/98:36 pmIAD - ISP
1 stop14h 01mMultiple Airlines
Mon 11/108:02 pmISP - IAD
2 stops24h 18mMultiple Airlines
Deal found 10/28$284
This Kiwi.com deal was found by Cheapflights users on 10/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 11/118:40 amIAD - ISP
2 stops25h 57mFrontier
Sat 11/154:58 pmISP - IAD
1 stop26h 53mFrontier
Deal found 10/27$294
This Kiwi.com deal was found by Cheapflights users on 10/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 12/47:57 pmIAD - ISP
2 stops23h 37mMultiple Airlines
Sun 12/712:00 pmISP - IAD
1 stop7h 55mMultiple Airlines
Deal found 10/27$337
This Kiwi.com deal was found by Cheapflights users on 10/27. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 11/148:36 pmIAD - ISP
1 stop14h 01mMultiple Airlines
Sun 11/1612:00 pmISP - IAD
1 stop7h 55mMultiple Airlines
Deal found 10/27$379
This Trip.com deal was found by Cheapflights users on 10/27. 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.
Fri 10/315:34 pmIAD - ISP
2 stops17h 03mFrontier
Sun 11/29:27 pmISP - IAD
2 stops26h 44mFrontier
Deal found 10/27$390
This Frontier deal was found by Cheapflights users on 10/28. 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.
Mon 11/242:11 pmIAD - ISP
1 stop9h 48mFrontier
Wed 11/266:00 amISP - IAD
1 stop10h 31mFrontier
Deal found 10/28$405

Cheapflights Fare Finder

 
Customize your flight search to find flights from Dulles Intl to Islip 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 October 28, 2025.
Use the filters below to find and compare flights from Washington, D.C. Dulles Intl Airport to Islip that are best for you.

Fly from

Dulles Intl

Fly to

Islip

Route

Depart

Return

Price

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Thu 11/20

11:12 am-10:37 am

1 stop23h 25m

Islip Long Island

Sun 11/23

8:25 pm-7:45 am

1 stop11h 20m

$140

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Thu 11/27

11:12 am-10:37 am

1 stop23h 25m

Islip Long Island

Tue 12/2

8:29 pm-2:29 pm

2 stops18h 00m

$181

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Thu 11/20

5:40 pm-10:37 am

2 stops16h 57m

Islip Long Island

Sun 11/23

8:25 pm-7:45 am

1 stop11h 20m

$278

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Fri 11/14

8:36 pm-10:37 am

1 stop14h 01m

Islip Long Island

Sun 11/16

12:00 pm-7:55 pm

1 stop7h 55m

$379

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Mon 11/24

2:11 pm-11:59 pm

1 stop9h 48m

Islip Long Island

Wed 11/26

6:00 am-4:31 pm

1 stop10h 31m

$405

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Fri 11/7

8:36 pm-10:37 am

1 stop14h 01m

Islip Long Island

Sun 11/9

12:00 pm-7:55 pm

1 stop7h 55m

$492

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Mon 11/10

8:36 pm-5:42 pm

1 stop21h 06m

Islip Long Island

Fri 11/14

2:25 pm-12:11 am

2 stops9h 46m

$529

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Tue 11/25

8:44 am-8:14 pm

1 stop11h 30m

Islip Long Island

Sun 11/30

8:25 pm-7:45 am

1 stop11h 20m

$609

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Sat 11/22

1:33 pm-11:53 pm

1 stop10h 20m

Islip Long Island

Sun 11/30

8:25 pm-7:45 am

1 stop11h 20m

$613

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Mon 11/24

8:40 am-7:45 pm

2 stops11h 05m

Islip Long Island

Wed 11/26

11:03 am-10:17 am

1 stop23h 14m

$618

Flights are sorted by cheapest round-trip flights first.

Deals found on 10/27

Showing 1-10 of 22 results
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Compare providers for flights from Dulles Intl 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 Dulles Intl to Islip in October.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy2 starsTrust Score*3 stars
FlightHubPrice Accuracy3 starsTrust Score*1 star
eDreamsPrice Accuracy3 starsTrust 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 Washington, D.C. Dulles Intl Airport-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 Washington, D.C. Dulles Intl Airport-Islip, New York flight deals on Cheapflights vs. eDreams >95% of the time. Price accuracy is based on data collected from Washington, D.C. Dulles Intl Airport-Islip, New York flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Washington, D.C. Dulles Intl Airport-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 Washington, D.C. Dulles Intl Airport-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 Dulles Intl to Islip

Have a flexible travel schedule? Discover the best time to fly to Islip from Dulles Intl 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 Washington, D.C. Dulles Intl Airport to Islip

What is the cheapest month to book a flight from Washington, D.C. Dulles Intl Airport to Islip, New York?

Currently, April is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Islip, New York (average of $67). Flying from Washington, D.C. Dulles Intl Airport to Islip, New York in January is currently the most expensive (average of $148). 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 Dulles Intl to Islip. Access travel guides, tips, and recommendations to enhance your travel experience. Get information about local attractions, weather, transportation options, and more.

  • What airport do you fly into for flights to Islip from Washington, D.C. Dulles Intl?

    Located just 7.2 mi from the city center, Islip Long Island is the airport most travelers will use when flying to Islip from Washington, D.C. Dulles Intl. Booking flights from Washington, D.C. Dulles Intl to Long Island (ISP) should be relatively easy as there are 0 daily inbound flights from Washington, D.C. Dulles Intl from 0 different airlines.

  • How long is the flight from Washington, D.C. Dulles Intl Airport to Islip, New York?

    There are many flights that can get you from Washington, D.C. Dulles Intl Airport to Islip, New York in 23h 25m. Fly via Frontier to get the fastest option. Airlines will cover a distance of 263 mi.

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

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

  • How can I find direct flights from Dulles Intl to Islip?

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

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

    Yes. Cheapflights offers flight deals from Dulles Intl 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 Washington, D.C. Dulles Intl Airport to Islip, New York?

    Currently, April is the cheapest month in which you can book a flight from Washington, D.C. Dulles Intl Airport to Islip, New York (average of $67). Flying from Washington, D.C. Dulles Intl Airport to Islip, New York in January is currently the most expensive (average of $148). 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 Islip?

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Alternative routes for Dulles Intl to Islip

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