$82 Cheap Flights from Islip (ISP) to Washington (IAD)

View $82 flight on Mon, Oct 20, 2025Opens in a new window

Popular airlines from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD)

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Cheap Flights from Islip to Washington (ISP-IAD)

Prices were available within the past 7 days and start at $82 for one-way flights and $178 for round trip, for the period specified. Prices and availability are subject to change. Additional terms apply.

Frontier Airlines
Mon, Oct 20 - Mon, Oct 27
ISP
Islip
IAD
Washington
$178 Roundtrip, found 2 hours ago
$178
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Mon, Oct 20 from Islip to Washington, returning Mon, Oct 27, priced at $178 found 2 hours ago
Frontier Airlines
Mon, Oct 20 - Fri, Oct 31
ISP
Islip
IAD
Washington
$192 Roundtrip, found 1 day ago
$192
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Mon, Oct 20 from Islip to Washington, returning Fri, Oct 31, priced at $192 found 1 day ago
Frontier Airlines
Wed, Oct 15 - Thu, Oct 16
ISP
Islip
IAD
Washington
$199 Roundtrip, found 2 hours ago
$199
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Wed, Oct 15 from Islip to Washington, returning Thu, Oct 16, priced at $199 found 2 hours ago
Frontier Airlines
Fri, Oct 17 - Mon, Oct 20
ISP
Islip
IAD
Washington
$213 Roundtrip, found 2 hours ago
$213
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Fri, Oct 17 from Islip to Washington, returning Mon, Oct 20, priced at $213 found 2 hours ago
Frontier Airlines
Thu, Oct 30 - Sun, Nov 2
ISP
Islip
IAD
Washington
$226 Roundtrip, found 2 hours ago
$226
Roundtrip
found 2 hours ago
Select Frontier Airlines flight, departing Thu, Oct 30 from Islip to Washington, returning Sun, Nov 2, priced at $226 found 2 hours ago
Frontier Airlines
Sat, Oct 4 - Fri, Oct 10
ISP
Islip
IAD
Washington
$234 Roundtrip, found 2 days ago
$234
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Sat, Oct 4 from Islip to Washington, returning Fri, Oct 10, priced at $234 found 2 days ago
Frontier Airlines
Mon, Oct 20 - Fri, Nov 7
ISP
Islip
IAD
Washington
$241 Roundtrip, found 1 day ago
$241
Roundtrip
found 1 day ago
Select Frontier Airlines flight, departing Mon, Oct 20 from Islip to Washington, returning Fri, Nov 7, priced at $241 found 1 day ago
Frontier Airlines
Sun, Sep 28 - Fri, Oct 10
ISP
Islip
IAD
Washington
$248 Roundtrip, found 2 days ago
$248
Roundtrip
found 2 days ago
Select Frontier Airlines flight, departing Sun, Sep 28 from Islip to Washington, returning Fri, Oct 10, priced at $248 found 2 days ago
Frontier Airlines
Sun, Sep 28 - Sun, Oct 5
ISP
Islip
IAD
Washington
$253 Roundtrip, found 6 hours ago
$253
Roundtrip
found 6 hours ago
Select Frontier Airlines flight, departing Sun, Sep 28 from Islip to Washington, returning Sun, Oct 5, priced at $253 found 6 hours ago
Breeze Airways
Sun, Jan 18 - Sun, Feb 1
ISP
Islip
IAD
Washington
$555 Roundtrip, found 1 day ago
$555
Roundtrip
found 1 day ago
Select Breeze Airways flight, departing Sun, Jan 18 from Islip to Washington, returning Sun, Feb 1, priced at $555 found 1 day ago

Alternative airports near Washington

Prices were available within the past 7 days. Prices and availability are subject to change.

Select flight to Ronald Reagan Washington National DCA. Closest option available. Average driving time to city center is 8 minutes. Flights from $409
DCA
Ronald Reagan Washington National
Closest
Average driving time to city center8 min
Flights from $409

Frequently asked questions

How much does a flight from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD) cost?
Snag a cheap one-way flight from $82 or cheap return flight from $178 from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD) with Expedia. Enter your travel dates and sort by "Price (lowest to highest)" to see our cheapest flight deals on this route.
What is the cheapest month to fly from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD)?
October is the least expensive month to fly from ISP to IAD. Avoiding peak travel times is often the key to finding better fares.
Which airlines fly direct from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD)?
There aren't any direct flights from Islip, NY (ISP-MacArthur) to Washington Dulles Intl. Airport (IAD). However, there are other airports with nonstop flights. Start your journey at John F. Kennedy Intl. Airport (JFK) and head straight to Washington without any detours.
What is the cheapest airline that flies from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD)?
Expedia's filter tool lets you easily compare different airlines, departure times and fares all in one place. Select your preferences, then sort by "Price (lowest to highest)" to find out which carrier offers the cheapest ISP to IAD flight.
How many flights per day from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD)?
Nonstop flights from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD) aren't available daily, so you'll need to take a flight with a layover. Explore your options with Expedia's filter tool. Enter your travel dates and pick either "1 Stop" or "2+ Stops."
What day of the week has the most flights from ISP to IAD?
You'll usually find Tuesday the quietest day for flights, while Fridays are often the busiest.* However this can vary from season to season and during public holidays or peak travel times.*Busiest/quietest day to travel is based on Expedia flight demand through January to December 2024.
What is the best time to fly from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD)?
To reach Washington Dulles Intl. Airport (IAD) without delays, opt for a flight that leaves MacArthur Airport (ISP) before 3 PM. The likelihood of cancellations is 22% higher, on average, for departures after this hour.**Most reliable time of the day and month to travel recommendation is based on January through August 2024 flight status data sourced from OAG's global flight data platform.
What airports do you fly into for Washington from MacArthur Airport (ISP)?
Explore your flight options from MacArthur Airport (ISP) to Baltimore Washington Intl. Thurgood Marshall Airport (BWI). This is the only airport in Washington you can land at if you're taking a direct flight.
Is it cheaper to buy a plane ticket from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD) last-minute?
Last-minute fares from ISP to IAD are typically more expensive. To secure the best rates, start searching for flights as soon as possible. That said, if you can play around with your travel dates, it's possible to score a cheap ticket right before your journey.
Is it cheaper to book an ISP to IAD flight and hotel package?
You can save money by booking an ISP to IAD flight and hotel package compared to booking separately. In fact, you could save hundreds of dollars by bundling with Expedia. And it's easy to manage everything in one convenient place. After selecting your preferred flights and accommodations, consider adding extras like tours, car rentals and activities.
Can I cancel or change the date of my flight from MacArthur Airport (ISP) to Washington Dulles Intl. Airport (IAD)?
Typically, it's possible to cancel or reschedule your ISP to IAD flight. However, if the booking was made more than 24 hours ago, additional fees may apply. Check your airline's policies in your itinerary to see what changes are possible and if any costs are involved. You'll also find more information on our Customer Service portal.

Travel information

Travel information

Origin airport
MacArthur
Destination airport
Washington Dulles Intl.
Airlines serving
Breeze Airways, Frontier Airlines
Roundtrip price
$164
Distance
263 mi

Book with confidence

Book with confidence

Islip to Washington Flights

The cheapest times to fly from Islip to Washington

On average, Thursday can be the cheapest time to fly, according to data from the Airlines Reporting Corporation (ARC), one of the world's biggest databases for global airline sales. The data reveals that you could save up to 16% by flying on a Thursday—the cheapest day to travel on average—instead of a Sunday—the most expensive. Some of the most affordable flights from Islip to Washington are during the month of October. You can find some of the cheapest flights from Islip to Washington with Expedia's search tool and vast selection of airlines.

 

The best time to book a flight from Islip to Washington

Sunday is one of the best days to book for cheap flights from Islip to Washington: Tickets reserved on a Sunday cost between 6% and 13% less than those reserved on a Friday, according to ARC data. The data also suggests booking early can also lead to cheaper airfares. You could save 24% by buying your tickets for domestic flights at least a month in advance and 10% by booking international flights 2 months in advance.

 

How to find cheap round-trip tickets from Islip to Washington

Being flexible with your dates and using Expedia's Price Drop Protection and Price Tracking features are some of the best ways of finding a cheap ticket from Islip to Washington in 2025. You can also book with separate airlines for your outbound and return journeys, from $82 one-way. Expedia also offers Price Drop Protection, so if the cost of your airfare goes down after booking, you'll receive a credit for the difference*. This is available for a small fee, and is free to One Key Gold and Platinum tier members.

 

Expedia's Price Tracking feature means you can stay on top of airfares without manually checking every day. It sends you automated price alerts for cheap Islip to Washington flights and uses historical data to indicate when the best time to book is. Download Expedia's free app to activate this handy tool in a few easy taps.

 

You could also save big by booking one of Expedia's vacation packages. Bundling together your Islip to Washington airfare with your accommodations and car rental is often cheaper than booking everything separately. There’s also One Key, Expedia's generous rewards program. Join for free and you could earn One Key cash on most bookings to save on future adventures.

 

*Terms apply.

 

Disclaimer: ARC The statistics are based on average round-trip ticket prices between January and August 2023. The percentages you see are averages.

 

Islip to Washington Flights

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