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Islip

$100+ 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 8/29. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — ISP
ago. 22 — ago. 291
sáb. 8/22
sáb. 8/29
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 julio 23, 2026.

This Expedia deal was found by Cheapflights users on 7/22. 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.
jue. 8/274:52 pm
IAD
-
ISP
1 stop17h 01m
Frontier
mar. 9/110:57 am
ISP
-
IAD
1 stop23h 10m
Frontier
Deal found 7/22$234
This Expedia deal was found by Cheapflights users on 7/19. 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.
vie. 8/2112:28 pm
IAD
-
ISP
1 stop6h 33m
Frontier
dom. 8/237:09 pm
ISP
-
IAD
1 stop14h 41m
Frontier
Deal found 7/19$248
This Trip.com deal was found by Cheapflights users on 7/21. 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.
mié. 8/1911:05 am
IAD
-
ISP
1 stop22h 48m
Frontier
vie. 8/217:46 pm
ISP
-
IAD
1 stop15h 57m
Frontier
Deal found 7/21$253
This Frontier deal was found by Cheapflights users on 7/23. 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.
vie. 10/29:21 am
IAD
-
ISP
1 stop9h 30m
Frontier
dom. 10/47:46 pm
ISP
-
IAD
1 stop12h 40m
Frontier
Deal found 7/23$258
This Kiwi.com deal was found by Cheapflights users on 7/19. 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.
mié. 9/211:05 am
IAD
-
ISP
1 stop22h 48m
Multiple Airlines
mar. 9/85:27 pm
ISP
-
IAD
2 stops43h 40m
Multiple Airlines
Deal found 7/19$261
This Kiwi.com deal was found by Cheapflights users on 7/22. 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.
mar. 9/811:05 am
IAD
-
ISP
1 stop22h 28m
Multiple Airlines
mar. 9/1512:00 pm
ISP
-
IAD
2 stops49h 07m
Multiple Airlines
Deal found 7/22$263
This Trip.com deal was found by Cheapflights users on 7/21. 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.
jue. 8/204:52 pm
IAD
-
ISP
1 stop17h 01m
Frontier
lun. 8/247:09 pm
ISP
-
IAD
1 stop14h 58m
Frontier
Deal found 7/21$266
This Frontier deal was found by Cheapflights users on 7/22. 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.
jue. 9/179:21 am
IAD
-
ISP
1 stop9h 30m
Frontier
dom. 9/207:46 pm
ISP
-
IAD
1 stop12h 40m
Frontier
Deal found 7/22$278
This Kiwi.com deal was found by Cheapflights users on 7/21. 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.
mar. 9/111:05 am
IAD
-
ISP
1 stop22h 48m
Frontier
sáb. 9/510:57 am
ISP
-
IAD
2 stops11h 55m
Frontier
Deal found 7/21$292
This Kiwi.com deal was found by Cheapflights users on 7/22. 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.
mar. 9/811:05 am
IAD
-
ISP
1 stop22h 28m
Frontier
mar. 9/154:13 pm
ISP
-
IAD
1 stop26h 56m
Frontier
Deal found 7/22$294
This Orbitz deal was found by Cheapflights users on 7/19. 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 Orbitz is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
lun. 8/1012:28 pm
IAD
-
ISP
1 stop6h 33m
Frontier
mié. 8/1210:57 am
ISP
-
IAD
1 stop25h 50m
Frontier
Deal found 7/19$298
This Kiwi.com deal was found by Cheapflights users on 7/22. 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.
jue. 9/178:00 pm
IAD
-
ISP
1 stop13h 33m
Multiple Airlines
sáb. 9/1912:00 pm
ISP
-
IAD
2 stops12h 28m
Multiple Airlines
Deal found 7/22$312

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 julio 23, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$234
(Expedia)

One-way from

$100
(Frontier)

Popular in

March

Cheapest in

November

Average price

$241
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. 7% potential increase in price ($17 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 3% potential price decrease ($7 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in July 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 julio 23, 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

Fly to

Route

Depart

Return

Price

Cheapest round-trip

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

jue. 8/27

4:52 pm-9:53 am

1 stop17h 01m

Islip Long Island

mar. 9/1

10:57 am-10:07 am

1 stop23h 10m

$234

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

sáb. 8/22

12:28 pm-7:01 pm

1 stop6h 33m

Islip Long Island

dom. 8/23

7:46 pm-11:43 am

1 stop15h 57m

$248

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

vie. 8/21

12:28 pm-7:01 pm

1 stop6h 33m

Islip Long Island

dom. 8/23

7:09 pm-9:50 am

1 stop14h 41m

$248

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

vie. 8/21

12:00 pm-9:53 am

2 stops21h 53m

Islip Long Island

lun. 8/24

7:09 pm-10:07 am

1 stop14h 58m

$363

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

vie. 8/21

4:52 pm-9:53 am

1 stop17h 01m

Islip Long Island

dom. 8/23

7:09 pm-11:20 am

2 stops16h 11m

$381
Quickest round-trip

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

vie. 8/7

12:28 pm-7:01 pm

1 stop6h 33m

Islip Long Island

lun. 8/10

10:57 am-6:33 pm

1 stop7h 36m

$650

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

vie. 10/2

7:53 pm-2:45 pm

1 stop18h 52m

Islip Long Island

dom. 10/4

10:57 am-2:21 pm

2 stops27h 24m

$676

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

sáb. 9/5

10:15 pm-8:59 pm

1 stop22h 44m

Islip Long Island

lun. 9/7

2:16 pm-7:20 am

1 stop17h 04m

$743

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

mié. 9/2

10:15 pm-5:41 pm

1 stop19h 26m

Islip Long Island

mar. 9/8

7:31 am-7:20 am

1 stop23h 49m

$752

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

mar. 9/8

12:35 pm-8:15 pm

2 stops7h 40m

Islip Long Island

mar. 9/15

10:05 am-9:28 pm

2 stops11h 23m

$763

Flights are sorted by cheapest round-trip flights first.

Deals found on 7/19

Showing 1-10 of 20 resultsSorted by cheapest first
1
2

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 July.
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.

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 17h 01m. 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.

See more FAQs

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