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Islip

$83+ Cheap flights from Washington, D.C. (WAS) to Islip (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 9/25. Fares are subject to change and may not be available on all flights or dates of travel.
WAS — ISP
Oct 16 — Oct 231
Thu 10/16
Thu 10/23
1 adult, Economy
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Cheap flight deals from Washington, D.C. to Islip

Discover tips and strategies to find the most affordable flight options for your journey from Washington, D.C. (WAS) 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 September 16, 2025.

Round-trip from

$165
(Frontier)

One-way from

$83
(Frontier)

Popular in

January

Cheapest in

April

Average price

$486

Good round-trip deal

$304 or less

Good one-way deal

$306 or less
From Washington, D.C. (WAS) to Islip Long Island
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One-way flight from Washington, D.C. (WAS) to Islip Long Island
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Highest demand for flights based on searches. 11% potential increase in price ($52 potential increase over avg. RT price).
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Cheapest flight prices on average. 3% potential price decrease ($12 potential savings vs. average RT price).
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Average for round-trip flights in September 2025
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Price to beat on a round-trip flight from Washington, D.C. (WAS) to Islip Long Island.
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Price to beat on a one-way flight from Washington, D.C. (WAS) to Islip Long Island.
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Find flight deals from Washington, D.C. to Islip

Cheapest flights from Washington, D.C. to Islip
Explore the most affordable flight options available from Washington, D.C. to Islip. Find the lowest fares from popular airlines and budget airlines, with prices last updated on September 16, 2025.

This Frontier deal was found by Cheapflights users on 9/14. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/38:21 amBWI - ISP
1 stop8h 06mFrontier
Sun 10/59:49 amISP - BWI
1 stop10h 16mFrontier
Deal found 9/14$165
This Frontier deal was found by Cheapflights users on 9/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 10/314:20 pmBWI - ISP
2 stops18h 17mFrontier
Sun 11/29:27 pmISP - BWI
1 stop11h 07mFrontier
Deal found 9/15$191
This Frontier deal was found by Cheapflights users on 9/14. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 10/1910:00 pmBWI - ISP
1 stop11h 04mFrontier
Thu 10/239:37 pmISP - BWI
1 stop10h 57mFrontier
Deal found 9/14$195
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/711:19 amBWI - ISP
1 stop9h 23mFrontier
Wed 10/84:58 pmISP - BWI
1 stop17h 32mFrontier
Deal found 9/14$196
This Frontier deal was found by Cheapflights users on 9/14. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/298:21 amBWI - ISP
1 stop8h 06mFrontier
Fri 10/39:49 amISP - BWI
2 stops14h 28mFrontier
Deal found 9/14$197
This Frontier deal was found by Cheapflights users on 9/14. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 9/188:59 pmIAD - ISP
1 stop12h 05mFrontier
Fri 9/269:49 amISP - IAD
1 stop10h 20mFrontier
Deal found 9/14$203
This Kiwi.com deal was found by Cheapflights users on 9/16. 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 10/148:00 amBWI - ISP
1 stop26h 57mMultiple Airlines
Tue 10/219:37 pmISP - BWI
1 stop15h 03mMultiple Airlines
Deal found 9/16$214
This Kiwi.com deal was found by Cheapflights users on 9/14. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 9/298:52 pmBWI - ISP
1 stop13h 48mMultiple Airlines
Fri 10/35:05 pmISP - BWI
1 stop22h 27mMultiple Airlines
Deal found 9/14$226
This Frontier deal was found by Cheapflights users on 9/15. 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 Frontier is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 10/156:45 pmBWI - ISP
2 stops14h 19mFrontier
Wed 10/2210:29 amISP - BWI
2 stops13h 24mFrontier
Deal found 9/15$229
This Kiwi.com deal was found by Cheapflights users on 9/15. 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 Kiwi.com is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sun 9/289:27 pmBWI - ISP
1 stop13h 13mMultiple Airlines
Sun 10/511:40 amISP - BWI
2 stops19h 49mMultiple Airlines
Deal found 9/15$232
This Trip.com deal was found by Cheapflights users on 9/14. 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.
Fri 9/267:14 pmIAD - ISP
1 stop15h 41mFrontier
Sun 9/289:49 amISP - IAD
1 stop11h 30mFrontier
Deal found 9/14$232
This Southwest deal was found by Cheapflights users on 9/16. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Tue 10/73:00 pmBWI - ISP
Nonstop1h 05mSouthwest
Wed 10/86:00 amISP - BWI
Nonstop1h 15mSouthwest
Deal found 9/16$237

Cheapflights Fare Finder

 
Customize your flight search to find flights from Washington, D.C. 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 September 16, 2025.
Use the filters below to find and compare flights from Washington, D.C. to Islip that are best for you.

Fly from

Washington, D.C.

Fly to

Islip

Route

Depart

Return

Price

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Fri 10/3

8:21 am-4:27 pm

1 stop8h 06m

Islip Long Island

Sun 10/5

9:49 am-8:05 pm

1 stop10h 16m

$165

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Tue 10/14

8:00 am-10:57 am

1 stop26h 57m

Islip Long Island

Tue 10/21

9:37 pm-12:40 pm

1 stop15h 03m

$214

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Fri 10/31

4:20 pm-10:37 am

2 stops18h 17m

Islip Long Island

Sun 11/2

9:27 pm-3:30 pm

2 stops18h 03m

$224

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Mon 9/29

8:52 pm-10:40 am

1 stop13h 48m

Islip Long Island

Fri 10/3

5:05 pm-3:32 pm

1 stop22h 27m

$226

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Thu 10/9

6:06 pm-9:04 am

1 stop14h 58m

Islip Long Island

Mon 10/13

4:58 pm-10:20 am

1 stop17h 22m

$226

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Wed 10/15

6:45 pm-9:04 am

2 stops14h 19m

Islip Long Island

Wed 10/22

10:29 am-11:53 pm

2 stops13h 24m

$229

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Sun 9/28

9:27 pm-10:40 am

1 stop13h 13m

Islip Long Island

Sun 10/5

11:40 am-7:29 am

2 stops19h 49m

$232

Washington, D.C.Islip

IAD - ISP

IADISP

Washington, D.C. Dulles Intl

Fri 9/26

7:14 pm-10:55 am

1 stop15h 41m

Islip Long Island

Sun 9/28

9:49 am-9:19 pm

1 stop11h 30m

$232

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Wed 10/15

11:15 am-12:25 pm

Nonstop1h 10m

Islip Long Island

Wed 10/22

4:55 pm-6:10 pm

Nonstop1h 15m

$237

BaltimoreIslip

BWI - ISP

BWIISP

Baltimore/Washington

Tue 10/7

3:00 pm-4:05 pm

Nonstop1h 05m

Islip Long Island

Wed 10/8

6:00 am-7:15 am

Nonstop1h 15m

$237

Flights are sorted by cheapest round-trip flights first.

Deals found on 9/15

Showing 1-10 of 55 results
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Best time to book a flight from Washington, D.C. to Islip

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

What is the cheapest month to book a flight from Washington, D.C. to Islip?

Currently, January is the cheapest month in which you can book a flight from Washington, D.C. to Islip (average of $108). Flying from Washington, D.C. to Islip in November is currently the most expensive (average of $213). 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.

What is the cheapest time of day to fly from WAS to ISP?

Find hourly flight availability from Washington, D.C. to Islip. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated September 16, 2025.

When flying from Washington, D.C. to Islip, the time of day you fly usually plays a role in the price. Save by searching for a flight at noon, which can drop the price by up to 11% versus a flight in the morning.

How much does it cost to fly round-trip from Washington, D.C. to Islip?

Reviews of airlines servicing Islip

Get insights into the airlines that provide service to Islip. Read reviews, discover amenities, and learn about the overall travel experience offered by airlines. Use this information to make informed decisions when choosing an airline for your flight to Islip. Reviews last updated September 16, 2025.
Read through reviews of airlines operating flights from Washington, D.C. to Islip, such as Southwest. Reviews also offer insight into each airline's entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,242 reviews

Entertainment

7.5

Crew

8.6

Boarding

8.1

Food

7.0

Comfort

8.0

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines
Southwest
8.0
Very good
4,242 reviews
Southwest
8.0
Very good
4,242 reviews

Entertainment

7.5

Crew

8.6

Boarding

8.1

Food

7.0

Comfort

8.0

Overall

8.0

Reviews

1 / 20
2.0
Mediocre

Mike,Aug 2025

OKC - AUS

AC was not adequate, even on a night flight. WiFi subpar even for the airlines

Related info for your journey

Find useful and relevant information for your journey from Washington, D.C. 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.?

    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.. Booking flights from Washington, D.C. to Long Island (ISP) should be relatively easy as there are 0 daily inbound flights from Washington, D.C. from 1 airline.

  • How long is the flight from Washington, D.C. to Islip?

    Airlines like Frontier and Southwest fly from Washington, D.C. to Islip in about 6h 40m. The time it takes to get you to your destination can typically vary by up to 1h 26m. Airlines will cover a distance of 248 mi. Both multi-stop and nonstop flights can be found to your destination and back.

  • What are the most popular routes from Washington, D.C. to Islip?

    When deciding which route to take from Washington, D.C. to Islip consider Baltimore/Washington - Islip Long Island, Washington, D.C. Dulles Intl - Islip Long Island or Washington, D.C. Reagan-National - Islip Long Island as they are the most popular.

  • Can I find deals for flights from Washington, D.C. to Islip that include hotel bookings?

    Yes. In addition to deals on Washington, D.C. to Islip flights, Cheapflights offers vacation packages that include both flights and hotel.

  • How can I find direct flights from Washington, D.C. to Islip?

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

  • Can I find deals for business class flights from Washington, D.C. to Islip?

    Yes. Cheapflights offers flight deals from Washington, D.C. 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. to Islip?

    Currently, January is the cheapest month in which you can book a flight from Washington, D.C. to Islip (average of $108). Flying from Washington, D.C. to Islip in November is currently the most expensive (average of $213). 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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Riverhead
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Alternative routes for Washington, D.C. to Islip

See prices for flight routes from nearby airports that may be better suited for you.
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Top airline flying from Washington, D.C. to Islip

Discover the top airline that operate flights from Washington, D.C. to Islip. Compare their services, reliability, and customer satisfaction ratings to choose the airline that best suits your travel preferences and needs. Over the last 7 days, Cheapflights users made 2,558,603 searches. Data last updated September 16, 2025.
AirlineCheapestAverageFlexibilityOn-time
SouthwestCheapest$233Average$358FlexibilityNo cancel feeOn-time63%

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