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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 9/16. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — ISP
Sep 14 — Sep 211
Mon 9/14
Mon 9/21
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 August 15, 2026.

This Trip.com deal was found by Cheapflights users on 8/12. 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 9/2311:12 am -
1 stop5h 46m
Thu 9/245:43 pm -
1 stop16h 34m
Deal found 8/12$231
This Trip.com deal was found by Cheapflights users on 8/14. 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.
Sat 9/1911:12 am -
1 stop5h 46m
Sun 9/206:48 pm -
1 stop18h 05m
Deal found 8/14$235
This Kiwi.com deal was found by Cheapflights users on 8/11. 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 9/2411:12 am -
1 stop29h 46m
Mon 9/285:43 pm -
1 stop16h 34m
Deal found 8/11$238
This Expedia deal was found by Cheapflights users on 8/15. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 8/294:52 pm -
1 stop17h 01m
Tue 9/110:57 am -
1 stop23h 10m
Deal found 8/15$240
This Trip.com deal was found by Cheapflights users on 8/12. 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 9/2811:12 am -
1 stop5h 46m
Wed 9/305:43 pm -
1 stop16h 44m
Deal found 8/12$241
This Trip.com deal was found by Cheapflights users on 8/13. 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 9/1111:12 am -
1 stop5h 46m
Sat 9/125:43 pm -
1 stop16h 44m
Deal found 8/13$245
This Trip.com deal was found by Cheapflights users on 8/11. 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 9/2511:12 am -
1 stop5h 46m
Mon 9/285:43 pm -
1 stop16h 34m
Deal found 8/11$250
This Trip.com deal was found by Cheapflights users on 8/11. 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 8/3112:28 pm -
1 stop6h 33m
Tue 9/810:57 am -
1 stop23h 20m
Deal found 8/11$262
This Trip.com deal was found by Cheapflights users on 8/13. 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 10/911:12 am -
1 stop6h 48m
Mon 10/126:55 pm -
1 stop15h 22m
Deal found 8/13$265
This Trip.com deal was found by Cheapflights users on 8/13. 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 9/1011:12 am -
1 stop5h 46m
Fri 9/116:48 pm -
1 stop23h 45m
Deal found 8/13$276
This Kiwi.com deal was found by Cheapflights users on 8/11. 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 9/2411:12 am -
1 stop29h 46m
Mon 9/2811:08 am -
2 stops9h 01m
Deal found 8/11$281

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 August 15, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$231
(Trip.com)

One-way from

$100
(Frontier)

Popular in

March

Cheapest in

November

Average price

$261
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. 4% potential increase in price ($11 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 2% potential price decrease ($6 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in August 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 August 15, 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 Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Fri 9/18

10:27 am-4:58 pm

1 stop6h 31m

Islip Long Island

Sun 9/20

6:48 pm-12:53 pm

1 stop18h 05m

$308

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Mon 8/24

10:45 am-6:14 pm

1 stop7h 29m

Islip Long Island

Tue 8/25

5:27 pm-5:14 pm

2 stops23h 47m

$446

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Thu 8/27

12:28 pm-7:01 pm

1 stop6h 33m

Islip Long Island

Sat 8/29

11:57 am-10:52 pm

2 stops10h 55m

$541

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Sat 9/5

10:15 pm-12:30 pm

1 stop14h 15m

Islip Long Island

Mon 9/7

7:31 am-7:20 am

1 stop23h 49m

$738

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Sun 9/13

6:15 am-12:30 pm

2 stops6h 15m

Islip Long Island

Fri 9/18

7:05 am-7:20 am

1 stop24h 15m

$754

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Mon 9/28

10:25 pm-10:56 am

1 stop12h 31m

Islip Long Island

Wed 9/30

7:31 am-4:23 pm

2 stops8h 52m

$754

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Fri 9/11

8:35 am-8:59 pm

2 stops12h 24m

Islip Long Island

Sat 9/12

9:05 am-4:09 pm

1 stop7h 04m

$824
Quickest round-trip

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Thu 9/10

12:35 pm-8:15 pm

2 stops7h 40m

Islip Long Island

Fri 9/11

7:05 am-4:35 pm

2 stops9h 30m

$907

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Tue 10/13

6:45 am-7:45 pm

2 stops13h 00m

Islip Long Island

Wed 10/14

7:25 am-7:20 am

1 stop23h 55m

$933

Washington, D.C.Islip

IAD Washington, D.C. Dulles Intl - ISP Islip Long Island

IADISP

Washington, D.C. Dulles Intl

Sun 9/13

10:15 pm-10:56 am

1 stop12h 41m

Islip Long Island

Sun 9/20

7:05 am-7:20 am

1 stop24h 15m

$944

Flights are sorted by cheapest round-trip flights first.

Deals found on 8/10

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 August.
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 6h 31m. 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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