HomeSearch by dateVacation packagesHotelsFlight dealsCar rentalTravel tips & news
Islip

$80+ 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 1/10. Fares are subject to change and may not be available on all flights or dates of travel.
IAD — ISP
Jan 11 — Jan 181
Sun 1/11
Sun 1/18
1 adult, Economy
We work with more than 300 partners to bring you better travel deals

Find cheap flights from Dulles Intl to Islip with Cheapflights

1. Tell us where you want to go

Enter your travel information like dates, passengers, trip type (one-way or round trip), and preferred cabin class then click “Find deals”

2. Select your favorite providers

We find the providers serving your travel needs. Choose up to four travel providers to compare side-by-side for flights, hotels, or car rentals.

3. Compare prices and book

Review each provider’s pricing and select the best option for you! Book through your favorite provider’s website for a seamless experience.

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 December 12, 2025.

This Expedia deal was found by Cheapflights users on 12/11. 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 Expedia is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 12/139:20 pmIAD - ISP
1 stop13h 00mFrontier
Sun 12/1412:07 pmISP - IAD
1 stop20h 24mFrontier
Deal found 12/11$327
This Kiwi.com deal was found by Cheapflights users on 12/10. 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 12/129:20 pmIAD - ISP
1 stop11h 53mMultiple Airlines
Sun 12/1411:15 amISP - IAD
2 stops27h 55mMultiple Airlines
Deal found 12/10$386
This Kiwi.com deal was found by Cheapflights users on 12/10. 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 12/1110:38 amIAD - ISP
2 stops46h 35mMultiple Airlines
Thu 12/1812:00 pmISP - IAD
1 stop7h 55mMultiple Airlines
Deal found 12/10$407
This Kiwi.com deal was found by Cheapflights users on 12/9. 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 12/149:20 pmIAD - ISP
1 stop11h 53mMultiple Airlines
Mon 12/152:25 pmISP - IAD
2 stops24h 04mMultiple Airlines
Deal found 12/9$533
This Kiwi.com deal was found by Cheapflights users on 12/11. 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.
Sat 12/139:20 pmIAD - ISP
1 stop13h 00mMultiple Airlines
Sun 12/146:35 pmISP - IAD
2 stops23h 56mMultiple Airlines
Deal found 12/11$592
This Kiwi.com deal was found by Cheapflights users on 12/9. 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.
Wed 12/247:01 pmIAD - ISP
2 stops16h 24mFrontier
Sun 12/288:35 pmISP - IAD
1 stop24h 28mFrontier
Deal found 12/9$593
This Kiwi.com deal was found by Cheapflights users on 12/10. 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 12/289:58 pmIAD - ISP
1 stop15h 11mFrontier
Mon 12/298:35 pmISP - IAD
2 stops15h 03mFrontier
Deal found 12/10$608
This Kiwi.com deal was found by Cheapflights users on 12/10. 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 12/259:41 amIAD - ISP
1 stop13h 50mFrontier
Mon 12/292:04 pmISP - IAD
1 stop6h 59mFrontier
Deal found 12/10$647
This Kiwi.com deal was found by Cheapflights users on 12/10. 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.
Mon 12/159:26 amIAD - ISP
1 stop14h 33mFrontier
Wed 12/1712:37 pmISP - IAD
1 stop20h 09mFrontier
Deal found 12/10$655
This Frontier deal was found by Cheapflights users on 12/9. 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.
Fri 12/1910:43 amIAD - ISP
1 stop13h 16mFrontier
Sun 12/212:04 pmISP - IAD
1 stop6h 59mFrontier
Deal found 12/9$656

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 December 12, 2025.

Most accurate provider

eDreams
3 stars

Most trusted provider

eDreams
3 stars

Round-trip from

$190
(Kiwi.com)

One-way from

$80
(Kiwi.com)

Popular in

January

Cheapest in

April

Average price

$189
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. 6% potential increase in price ($13 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 December 2025
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 December 12, 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

Sat 1/10

10:03 am-7:08 pm

1 stop9h 05m

Islip Long Island

Mon 1/12

2:01 pm-11:43 am

2 stops21h 42m

$190

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Sun 1/4

9:58 pm-1:09 pm

1 stop15h 11m

Islip Long Island

Thu 1/15

7:58 pm-7:58 pm

1 stop24h 00m

$262

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Mon 1/5

10:43 am-11:59 pm

1 stop13h 16m

Islip Long Island

Thu 1/15

7:58 pm-7:58 pm

1 stop24h 00m

$392

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Sun 12/14

9:20 pm-9:13 am

1 stop11h 53m

Islip Long Island

Mon 12/15

2:25 pm-2:29 pm

2 stops24h 04m

$533

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Wed 12/24

7:01 pm-11:25 am

2 stops16h 24m

Islip Long Island

Sun 12/28

8:35 pm-9:03 pm

1 stop24h 28m

$593

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Sun 12/28

9:58 pm-1:09 pm

1 stop15h 11m

Islip Long Island

Mon 12/29

8:35 pm-11:38 am

2 stops15h 03m

$608

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Thu 1/8

2:10 pm-11:15 am

1 stop21h 05m

Islip Long Island

Thu 1/15

12:00 pm-8:06 pm

1 stop8h 06m

$631

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Thu 12/25

9:41 am-11:31 pm

1 stop13h 50m

Islip Long Island

Mon 12/29

2:04 pm-9:03 pm

1 stop6h 59m

$647

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Mon 12/15

9:26 am-11:59 pm

1 stop14h 33m

Islip Long Island

Wed 12/17

12:37 pm-8:46 am

1 stop20h 09m

$655

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Fri 12/19

10:43 am-11:59 pm

1 stop13h 16m

Islip Long Island

Sun 12/21

2:04 pm-9:03 pm

1 stop6h 59m

$656

Flights are sorted by cheapest round-trip flights first.

Deals found on 12/8

Showing 1-10 of 19 results
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 December.
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 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 15h 11m. 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?

Book flights to Islip if you plan to visit one of these locations
Riverhead

Browse thousands of different options on Cheapflights for your next trip

Toggle through the tabs below to find thousands of options on Cheapflights for your next trip.

Alternative routes for Dulles Intl to Islip

See prices for flight routes from nearby airports that may be better suited for you.
Dulles Intl to John F Kennedy Intl flights
Reagan-National to John F Kennedy Intl flights
Reagan-National to LaGuardia flights
Dulles Intl to Newark flights
Dulles Intl to LaGuardia flights
Reagan-National to Newark flights
Baltimore to LaGuardia flights
Baltimore to John F Kennedy Intl flights
Baltimore to Newark flights
Reagan-National to Buffalo flights
Dulles Intl to Buffalo flights
Baltimore to Buffalo flights
Dulles Intl to Stewart flights
Dulles Intl to White Plains flights
Reagan-National to White Plains flights
Dulles Intl to Rochester flights
Dulles Intl to Albany flights
Reagan-National to Rochester flights
Reagan-National to Syracuse flights
Baltimore to Stewart flights
Reagan-National to Albany flights
Baltimore to Rochester flights
Dulles Intl to Syracuse flights
Baltimore to Albany flights
Baltimore to White Plains flights
Reagan-National to Saranac Lake flights
Baltimore to Syracuse flights
Dulles Intl to Plattsburgh flights
Reagan-National to Ithaca flights
Baltimore to Islip flights
Dulles Intl to Ithaca flights
Baltimore to Plattsburgh flights
Reagan-National to Islip flights
Baltimore to Ithaca flights
Reagan-National to Rutland flights
Baltimore to Niagara Falls flights
Dulles Intl to Rutland flights
Reagan-National to Watertown flights
Baltimore to Rutland flights
Baltimore to Elmira flights
Dulles Intl to Elmira flights
Reagan-National to Stewart flights
Baltimore to Saranac Lake flights
Baltimore to Watertown flights
Dulles Intl to Watertown flights
Dulles Intl to Saranac Lake flights
Baltimore to Binghamton flights
Reagan-National to Binghamton flights
Dulles Intl to Binghamton flights

100% Free

Cheapflights is completely free to use, so you can start saving the moment you arrive.

Book with Flexibility

Our users can plan ahead with confidence and find flights with no change fees

Travel Smart

Millions of people come to us for their flight needs every year. We help make travel planning easy by providing useful insights and data-driven graphs that can inform your decisions.