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Washington, D.C.

$91+ Cheap flights from Islip, NY (ISP) to Washington, D.C. (WAS)

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 4/20. Fares are subject to change and may not be available on all flights or dates of travel.
ISP — WAS
Apr 27 — May 41
Mon 4/27
Mon 5/4
1 adult, Economy
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Cheap flight deals from Islip to Washington, D.C.

Cheapest flights from Islip to Washington, D.C.
Explore the most affordable flight options available from Islip to Washington, D.C.. Find the lowest fares from popular airlines and budget airlines, with prices last updated on March 28, 2026.

This Kiwi.com deal was found by Cheapflights users on 3/27. 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 6/411:00 am
ISP
-
BWI
2 stops20h 43m
Frontier
Tue 6/98:17 pm
BWI
-
ISP
1 stop13h 46m
Frontier
Deal found 3/27$198
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 4/168:31 pm
ISP
-
BWI
1 stop22h 29m
Frontier
Sun 4/199:10 pm
BWI
-
ISP
1 stop12h 03m
Frontier
Deal found 3/26$225
This Kiwi.com deal was found by Cheapflights users on 3/26. 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 6/1210:48 am
ISP
-
BWI
1 stop10h 16m
Frontier
Sun 6/149:59 pm
BWI
-
ISP
1 stop12h 04m
Frontier
Deal found 3/26$230
This Kiwi.com deal was found by Cheapflights users on 3/27. 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 6/411:00 am
ISP
-
BWI
1 stop8h 06m
Multiple Airlines
Tue 6/98:17 pm
BWI
-
ISP
1 stop13h 46m
Multiple Airlines
Deal found 3/27$241
This Kiwi.com deal was found by Cheapflights users on 3/25. 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.
Mon 4/204:07 pm
ISP
-
BWI
2 stops17h 08m
Multiple Airlines
Wed 4/225:35 pm
BWI
-
ISP
1 stop15h 58m
Multiple Airlines
Deal found 3/25$267
This Southwest deal was found by Cheapflights users on 3/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Mon 4/206:00 am
ISP
-
BWI
Nonstop1h 20m
Southwest
Wed 4/225:15 pm
BWI
-
ISP
Nonstop1h 15m
Southwest
Deal found 3/25$268
This Southwest deal was found by Cheapflights users on 3/26. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Sat 4/254:40 pm
ISP
-
BWI
Nonstop1h 20m
Southwest
Sat 5/210:25 am
BWI
-
ISP
Nonstop1h 10m
Southwest
Deal found 3/26$277
This Southwest deal was found by Cheapflights users on 3/27. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Thu 6/43:05 pm
ISP
-
BWI
Nonstop1h 15m
Southwest
Tue 6/910:40 am
BWI
-
ISP
Nonstop1h 10m
Southwest
Deal found 3/27$279
This Kiwi.com deal was found by Cheapflights users on 3/24. 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 5/811:00 am
ISP
-
BWI
1 stop12h 18m
Multiple Airlines
Fri 5/152:42 pm
BWI
-
ISP
1 stop19h 23m
Multiple Airlines
Deal found 3/24$283
This Kiwi.com deal was found by Cheapflights users on 3/24. 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 6/1210:48 am
ISP
-
BWI
1 stop22h 18m
Multiple Airlines
Mon 6/159:59 pm
BWI
-
ISP
2 stops18h 48m
Multiple Airlines
Deal found 3/24$293
This Southwest deal was found by Cheapflights users on 3/25. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Wed 4/222:30 pm
ISP
-
DCA
2 stops7h 55m
Southwest
Wed 4/296:05 am
DCA
-
ISP
1 stop10h 30m
Southwest
Deal found 3/25$346
This Southwest deal was found by Cheapflights users on 3/23. 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 Southwest is selected, and click “Compare selected” under the list of providers to see comparable flight deals.
Fri 4/245:10 pm
ISP
-
DCA
1 stop5h 40m
Southwest
Tue 4/281:00 pm
DCA
-
ISP
1 stop9h 40m
Southwest
Deal found 3/23$372

Find flight deals from Islip to Washington, D.C.

Discover tips and strategies to find the most affordable flight options for your journey from Islip (ISP) to Washington, D.C. (WAS). 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 March 28, 2026.

Most accurate provider

FlightHub
3 stars

Most trusted provider

FlightHub
3 stars

Round-trip from

$198
(Kiwi.com)

One-way from

$91
(Kiwi.com)

Popular in

July

Cheapest in

December

Average price

$478

Good round-trip deal

$338 or less

Good one-way deal

$192 or less
Provider with most accurate pricing for Islip Long Island-Washington, D.C. (WAS) flight deals.
Search Deals
Provider most trusted by Cheapflights users for Islip Long Island-Washington, D.C. (WAS) flights.
Search Deals
From Islip Long Island to Washington, D.C. (WAS)
Search Deals
One-way flight from Islip Long Island to Washington, D.C. (WAS)
Search Deals
Highest demand for flights based on searches. 27% potential increase in price ($170 potential increase over avg. RT price).
Search Deals
Cheapest flight prices on average. 8% potential price decrease ($35 potential savings vs. average RT price).
Search Deals
Average for round-trip flights in March 2026
Search Deals
Price to beat on a round-trip flight from Islip Long Island to Washington, D.C. (WAS).
Search Deals
Price to beat on a one-way flight from Islip Long Island to Washington, D.C. (WAS).
Search Deals

Cheapflights Fare Finder

 
Customize your flight search to find flights from Islip to Washington, D.C. 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 March 28, 2026.
Use the filters below to find and compare flights from Islip to Washington, D.C. that are best for you.

Fly from

Fly to

Route

Depart

Return

Price

Cheapest round-trip

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Sat 4/25

4:40 pm-6:00 pm

Nonstop1h 20m

Baltimore/Washington

Sat 5/2

10:25 am-11:35 am

Nonstop1h 10m

$277
Quickest round-trip

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Thu 6/4

3:05 pm-4:20 pm

Nonstop1h 15m

Baltimore/Washington

Tue 6/9

10:40 am-11:50 am

Nonstop1h 10m

$279

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Fri 5/29

11:00 am-11:18 pm

1 stop12h 18m

Baltimore/Washington

Sun 5/31

3:26 pm-10:05 am

1 stop18h 39m

$300

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Fri 5/1

8:35 am-9:55 am

Nonstop1h 20m

Baltimore/Washington

Sat 5/2

10:25 am-11:35 am

Nonstop1h 10m

$302

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Sat 4/25

9:20 am-10:40 am

Nonstop1h 20m

Baltimore/Washington

Sun 4/26

10:40 pm-11:50 pm

Nonstop1h 10m

$318

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Thu 4/23

12:30 pm-1:45 pm

Nonstop1h 15m

Baltimore/Washington

Sun 4/26

10:40 pm-11:50 pm

Nonstop1h 10m

$318

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Fri 4/17

6:00 am-7:20 am

Nonstop1h 20m

Baltimore/Washington

Mon 4/20

7:10 pm-8:25 pm

Nonstop1h 15m

$320

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Thu 4/16

4:30 pm-5:50 pm

Nonstop1h 20m

Baltimore/Washington

Sun 4/19

10:40 am-11:50 am

Nonstop1h 10m

$330

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Fri 5/8

11:00 am-11:18 pm

1 stop12h 18m

Baltimore/Washington

Fri 5/15

7:27 pm-11:17 am

2 stops15h 50m

$334

IslipBaltimore

ISP - BWI

ISPBWI

Islip Long Island

Fri 5/29

4:30 pm-5:50 pm

Nonstop1h 20m

Baltimore/Washington

Sun 5/31

10:40 pm-11:50 pm

Nonstop1h 10m

$343

Flights are sorted by cheapest round-trip flights first.

Deals found on 3/27

Showing 1-10 of 45 resultsSorted by cheapest first
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Compare providers for flights from Islip to Washington, D.C.

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 Islip to Washington, D.C. in March.
ProviderPrice AccuracyTrust Score*
FlightHubPrice Accuracy3 starsTrust Score*3 stars
ExpediaPrice Accuracy1 starTrust 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 Islip, New York-Washington, D.C. flights, users find the pricing of FlightHub to be most consistent on Cheapflights vs. FlightHub Users can find the same prices on Islip, New York-Washington, D.C. flight deals on Cheapflights vs. FlightHub >95% of the time. Price accuracy is based on data collected from Islip, New York-Washington, D.C. flight searches over the past month and is updated monthly.
  • Most trusted provider: When it comes to deals on Islip, New York-Washington, D.C. 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 Islip, New York-Washington, D.C. 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 Islip to Washington, D.C.

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

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

Currently, June is the cheapest month in which you can book a flight from Islip, New York to Washington, D.C. (average of $64). Flying from Islip, New York to Washington, D.C. in March is currently the most expensive (average of $124). 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 ISP to WAS?

Find hourly flight availability from Islip to Washington, D.C.. Discover flight options and departure times throughout the day, allowing you to choose a departure time that suits your schedule. Data last updated March 28, 2026.

When flying from Islip, New York to Washington, D.C., the time of day you fly usually plays a role in the price. Save by searching for a flight in the afternoon, which can drop the price by up to 19% versus a flight in the evening.

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

Reviews of airlines servicing Washington, D.C.

Get insights into the airlines that provide service to Washington, D.C.. 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 Washington, D.C.. Reviews last updated March 28, 2026.
Get a feel of what it's like to fly with Southwest from Islip to Washington, D.C. by reading reviews from past customers. Users have also rated airlines in terms of entertainment options, comfort, food, crew/service, and boarding process.
Southwest
8.0
Very good
4,333 reviews

Entertainment

7.5

Comfort

8.0

Overall

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.
Southwest
8.0
Very good
4,333 reviews
Southwest
8.0
Very good
4,333 reviews

Entertainment

7.5

Comfort

8.0

Overall

8.0

Boarding

8.1

Crew

8.6

Food

7.0

Reviews

1 / 20
2.0
Mediocre

Dominic,Mar 2026

MCO - SMF

I had to try and sleep on the floor of the Austin airport. I spent 12 hours there. The airline policies were so poor, that a near violent argument broke out between the people in front of me and the flight attendants - making for a super stressful situation at 30,000 feet. Garbage airline choice by Kayak Garbage idea to book a flight with a layover. Next time I will pay for a quality booking myself, and somehow force the company to reimburse it.

Related info for your journey

Find useful and relevant information for your journey from Islip to Washington, D.C.. 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 from for flights from Islip to 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 Washington, D.C. from Islip. Booking flights from Long Island (ISP) to Washington, D.C. should be relatively easy as there are 0 daily outbound flights to Washington, D.C. from 1 airline.

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

    There are many flights that can get you from Islip, New York to Washington, D.C. in 1h 20m. Fly via Southwest to get the fastest option. The distance between Islip, New York and Washington, D.C. is about 219 mi. All flights are typically nonstop.

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

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

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

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

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

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

    Currently, June is the cheapest month in which you can book a flight from Islip, New York to Washington, D.C. (average of $64). Flying from Islip, New York to Washington, D.C. in March is currently the most expensive (average of $124). 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 Washington, D.C.?

Book flights to Washington, D.C. if you plan to visit one of these locations
Alexandria
Woodbridge
Tysons
Owings Mills
Arlington
Springfield
Silver Spring
Herndon
Hyattsville
Hanover
Laurel
Rockville
Upper Marlboro
Fredericksburg
Largo
Bowie
Clinton
Towson
College Park
Cordova

Browse thousands of different options on Cheapflights for your next trip

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Top airline flying from Islip to Washington, D.C.

Discover the top airline that operate flights from Islip to Washington, D.C.. 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 March 28, 2026.
AirlineCheapestAverageFlexibilityOn-time
SouthwestCheapest$245Average$395FlexibilityNo cancel feeOn-time63%

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