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Islip

$188+ 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 2/22. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — ISP
Feb 26 — Mar 51
Thu 2/26
Thu 3/5
1 adult, Economy
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Cheap 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 January 27, 2026.

This Trip.com deal was found by Cheapflights users on 1/26. 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 Trip.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 3/128:15 am
IAD
-
ISP
1 stop7h 58m
Frontier
Thu 3/194:34 pm
ISP
-
IAD
1 stop14h 50m
Frontier
Deal found 1/26$309
This Expedia deal was found by Cheapflights users on 1/25. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 1/309:35 am
IAD
-
ISP
1 stop11h 12m
Frontier
Sun 2/19:25 am
ISP
-
IAD
1 stop27h 11m
Frontier
Deal found 1/25$310
This Kiwi.com deal was found by Cheapflights users on 1/26. 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 3/128:15 am
IAD
-
ISP
1 stop7h 58m
Multiple Airlines
Thu 3/197:26 pm
ISP
-
IAD
2 stops35h 58m
Multiple Airlines
Deal found 1/26$314
This Kiwi.com deal was found by Cheapflights users on 1/26. 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.
Fri 2/69:35 am
IAD
-
ISP
1 stop11h 12m
Frontier
Sun 2/87:53 pm
ISP
-
IAD
2 stops20h 35m
Frontier
Deal found 1/26$355
This Kiwi.com deal was found by Cheapflights users on 1/26. 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.
Fri 2/69:35 am
IAD
-
ISP
1 stop11h 12m
Multiple Airlines
Sun 2/89:25 am
ISP
-
IAD
2 stops28h 53m
Multiple Airlines
Deal found 1/26$357
This Kiwi.com deal was found by Cheapflights users on 1/25. 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.
Fri 1/309:35 am
IAD
-
ISP
1 stop11h 12m
Multiple Airlines
Sun 2/19:25 am
ISP
-
IAD
2 stops28h 53m
Multiple Airlines
Deal found 1/25$418
This Kiwi.com deal was found by Cheapflights users on 1/26. 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.
Fri 2/69:35 am
IAD
-
ISP
1 stop11h 12m
Frontier
Sun 2/158:01 pm
ISP
-
IAD
1 stop11h 19m
Frontier
Deal found 1/26$442
This Kiwi.com deal was found by Cheapflights users on 1/27. 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 2/55:37 pm
IAD
-
ISP
2 stops27h 10m
Multiple Airlines
Sun 2/810:31 am
ISP
-
IAD
1 stop7h 16m
Multiple Airlines
Deal found 1/27$463
This Kiwi.com deal was found by Cheapflights users on 1/26. 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.
Fri 2/69:35 am
IAD
-
ISP
2 stops25h 35m
Multiple Airlines
Sun 2/158:01 pm
ISP
-
IAD
1 stop11h 19m
Multiple Airlines
Deal found 1/26$493

Find 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 January 27, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$309
(Trip.com)

One-way from

$188
(Trip.com)

Popular in

October

Cheapest in

April

Average price

$207
Provider with most accurate pricing for Washington, D.C. Dulles Intl-Islip Long Island flight deals.
Search Deals
Provider most trusted by Cheapflights users for Washington, D.C. Dulles Intl-Islip Long Island flights.
Search Deals
From Washington, D.C. Dulles Intl to Islip Long Island
Search Deals
One-way flight from Washington, D.C. Dulles Intl to Islip Long Island
Search Deals
Highest demand for flights based on searches. 3% potential increase in price ($6 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($5 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in January 2026
Search Deals

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 January 27, 2026.
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 3/12

8:15 am-4:13 pm

1 stop7h 58m

Islip Long Island

Thu 3/19

4:34 pm-7:24 am

1 stop14h 50m

$309

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Fri 2/6

9:35 am-8:47 pm

1 stop11h 12m

Islip Long Island

Sun 2/8

9:25 am-12:36 pm

1 stop27h 11m

$310

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Thu 3/12

8:15 am-4:13 pm

1 stop7h 58m

Islip Long Island

Thu 3/19

7:26 pm-7:24 am

2 stops35h 58m

$314

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Fri 2/6

9:35 am-8:47 pm

1 stop11h 12m

Islip Long Island

Sun 2/15

8:01 pm-7:20 am

1 stop11h 19m

$442

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Fri 2/6

9:35 am-8:47 pm

1 stop11h 12m

Islip Long Island

Sun 2/8

10:31 am-5:47 pm

1 stop7h 16m

$471

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Fri 2/6

9:35 am-11:10 am

2 stops25h 35m

Islip Long Island

Sun 2/15

8:01 pm-7:20 am

1 stop11h 19m

$493

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Tue 2/10

1:30 am-2:39 pm

2 stops37h 09m

Islip Long Island

Sun 2/15

8:01 pm-7:20 am

1 stop11h 19m

$644

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Tue 3/17

7:00 am-8:55 am

2 stops25h 55m

Islip Long Island

Thu 3/19

9:45 am-7:24 am

1 stop21h 39m

$783

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Sun 2/22

9:07 pm-7:38 am

1 stop10h 31m

$188

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Sun 2/22

9:07 pm-1:31 pm

2 stops16h 24m

$225

Flights are sorted by cheapest round-trip flights first.

Deals found on 1/26

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 January.
ProviderPrice AccuracyTrust Score*
ExpediaPrice Accuracy1 starTrust Score*3 stars
FlightHubPrice 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 FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Washington, D.C. Dulles Intl Airport-Islip, New York flight deals on Cheapflights vs. FlightHub >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 FlightHub the most. FlightHub 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 July is currently the most expensive (average of $139). 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 7h 58m. 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 July is currently the most expensive (average of $139). 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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Dulles Intl to Binghamton flights
Reagan-National to Stewart flights
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